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Background: Intermittent smoking is prevalent among Hispanics, but little is known about whether this smoking pattern associates with increased chronic kidney disease (CKD) risk in this population. The objective of the present study is to identify patterns of exposure associated with CKD in US Hispanics., Methods: We used cross-sectional data on 15 410 participants of the Hispanics Community Health Study/the Study of Latinos, a population-based study of individuals aged 18-74 years, recruited in 2008 to 2011 from four US field centers (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA). Smoking exposure was obtained through a questionnaire. CKD was defined by an estimated glomerular filtration rate of <60 mL/min/1.73 m(2) or a urine albumin-to-creatinine ratio of ≥30 mg/g., Results: Approximately 14% of individuals were daily and 7% were intermittent smokers, and 16% were past smokers. There was a significant interaction between smoking status and pack-years of exposure (P = 0.0003). In adjusted models, there was an increased odds of CKD among daily, intermittent and past smokers by pack-years compared with never smokers. The association of intermittent smokers was significant at 10 pack-years [odds ratio (OR) = 1.38, 95% confidence intervals (CI) 1.06, 1.81], whereas for daily smokers this association was observed at 40 pack-years (OR = 1.43, 95% CI 1.09, 1.89)., Conclusions: Our findings of increased risk of CKD among Hispanics who are intermittent smokers support screening and smoking cessation interventions targeted to this population for the prevention of CKD. It also suggests novel mechanistic pathways for kidney toxicity that should be further explored in future studies., (© The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Background: Non-Hispanic blacks and Hispanics with end-stage renal disease have a lower risk for death than non-Hispanic whites, but data for racial/ethnic variation in cardiovascular outcomes for non-dialysis-dependent chronic kidney disease are limited., Study Design: Prospective cohort., Setting & Participants: 3,785 adults with entry estimated glomerular filtration rates of 20 to 70mL/min/1.73m(2) enrolled in the CRIC (Chronic Renal Insufficiency Cohort) Study., Predictors: Race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic)., Outcomes: Cardiovascular outcomes (atherosclerotic events [myocardial infarction, stroke, or peripheral arterial disease] and heart failure) and a composite of each cardiovascular outcome or all-cause death., Measurements: Multivariable Cox proportional hazards., Results: During a median follow-up of 6.6 years, we observed 506 atherosclerotic events, 551 heart failure events, and 692 deaths. In regression analyses, there were no significant differences in atherosclerotic events among the 3 racial/ethnic groups. In analyses stratified by clinical site, non-Hispanic blacks had a higher risk for heart failure events (HR, 1.59; 95% CI, 1.29-1.95), which became nonsignificant after adjustment for demographic factors and baseline kidney function. In contrast, Hispanics had similar risk for heart failure events as non-Hispanic whites. In analyses stratified by clinical site, compared with non-Hispanic whites, non-Hispanic blacks were at similar risk for atherosclerotic events or death. However, after further adjustment for cardiovascular risk factors, medications, and mineral metabolism markers, non-Hispanic blacks had 17% lower risk for the outcome (HR, 0.83; 95% CI, 0.69-0.99) than non-Hispanic whites, whereas there was no significant association with Hispanic ethnicity., Limitations: Hispanics were largely recruited from a single center, and the study was underpowered to evaluate the association between Hispanic ethnicity and mortality., Conclusions: There were no significant racial/ethnic differences in adjusted risk for atherosclerotic or heart failure outcomes. Future research is needed to better explain the reduced risk for atherosclerotic events or death in non-Hispanic blacks compared with non-Hispanic whites., (Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background and Objectives: CKD is a global public health problem with significant mortality and morbidity., Design, Setting, Participants, & Measurements: We examined the multivariable association of plasma levels of IL-1, IL-1 receptor antagonist, IL-6, TNF-α, TGF-β, high-sensitivity C-reactive protein, fibrinogen, and serum albumin with progression of CKD in 3430 Chronic Renal Insufficiency Cohort study participants., Results: Over a median follow-up time of 6.3 years, 899 participants reached the composite end point of ≥50% decline in eGFR from baseline or onset of ESRD. Elevated plasma levels of fibrinogen, IL-6, and TNF-α and lower serum albumin were associated with a greater decline in eGFR over time. After adjusting for demographics, BP, laboratory variables, medication use, and baseline eGFR, hazard ratios for the composite outcome were greater for the patients in the highest quartile of fibrinogen (hazard ratio, 2.05; 95% confidence interval, 1.64 to 2.55; P<0.001), IL-6 (hazard ratio, 1.44; 95% confidence interval, 1.17 to 1.77; P<0.01), and TNF-α (hazard ratio, 1.94; 95% confidence interval, 1.52 to 2.47; P<0.001) compared with those in the respective lowest quartiles. The hazard ratio was 3.48 (95% confidence interval, 2.88 to 4.21; P<0.001) for patients in the lowest serum albumin quartile relative to those in the highest quartile. When also adjusted for albuminuria, the associations of fibrinogen (hazard ratio, 1.49; 95% confidence interval, 1.20 to 1.86; P<0.001), serum albumin (hazard ratio, 1.52; 95% confidence interval, 1.24 to 1.87; P<0.001), and TNF-α (hazard ratio, 1.42; 95% confidence interval, 1.11 to 1.81; P<0.001) with outcome were attenuated but remained significant., Conclusions: Elevated plasma levels of fibrinogen and TNF-α and decreased serum albumin are associated with rapid loss of kidney function in patients with CKD., (Copyright © 2016 by the American Society of Nephrology.)

Background: It is not clear whether the pattern of kidney function decline in patients with chronic kidney disease (CKD) may relate to outcomes after reaching end-stage renal disease (ESRD). We hypothesize that an abrupt decline in kidney function prior to ESRD predicts early death after initiating maintenance hemodialysis therapy., Study Design: Prospective cohort study., Setting & Participants: The Chronic Renal Insufficiency Cohort (CRIC) Study enrolled men and women with mild to moderate CKD. For this study, we studied 661 individuals who developed chronic kidney failure that required hemodialysis therapy initiation., Predictors: The primary predictor was the presence of an abrupt decline in kidney function prior to ESRD. We incorporated annual estimated glomerular filtration rates (eGFRs) into a mixed-effects model to estimate patient-specific eGFRs at 3 months prior to initiation of hemodialysis therapy. Abrupt decline was defined as having an extrapolated eGFR≥30mL/min/1.73m(2) at that time point., Outcomes: All-cause mortality within 1 year after initiating hemodialysis therapy., Measurements: Multivariable Cox proportional hazards., Results: Among 661 patients with CKD initiating hemodialysis therapy, 56 (8.5%) had an abrupt predialysis decline in kidney function and 69 died within 1 year after initiating hemodialysis therapy. After adjustment for demographics, cardiovascular disease, diabetes, and cancer, abrupt decline in kidney function was associated with a 3-fold higher risk for death within the first year of ESRD (adjusted HR, 3.09; 95% CI, 1.65-5.76)., Limitations: Relatively small number of outcomes; infrequent (yearly) eGFR determinations; lack of more granular clinical data., Conclusions: Abrupt decline in kidney function prior to ESRD occurred in a significant minority of incident hemodialysis patients and predicted early death in ESRD., (Copyright © 2016 National Kidney Foundation, Inc. All rights reserved.)

Background and Objectives: Low health-related quality of life is associated with increased mortality in patients with ESRD. However, little is known about demographic and clinical factors associated with health-related quality of life or its effect on outcomes in adults with CKD., Design, Settings, Participants, & Measurements: Data from 3837 adult participants with mild to severe CKD enrolled in the prospective observational Chronic Renal Insufficiency Cohort and Hispanic Chronic Renal Insufficiency Cohort Studies were analyzed. Health-related quality of life was assessed at baseline with the Kidney Disease Quality of Life-36 and its five subscales: mental component summary, physical component summary, burden of kidney disease (burden), effects of kidney disease (effects), and symptoms and problems of kidney disease (symptoms). Low health-related quality of life was defined as baseline score >1 SD below the mean. Using Cox proportional hazards analysis, the relationships between low health-related quality of life and the following outcomes were examined: (1) CKD progression (50% eGFR loss or incident ESRD), (2) incident cardiovascular events, and (3) all-cause death., Results: Younger age, women, low education, diabetes, vascular disease, congestive heart failure, obesity, and lower eGFR were associated with low baseline health-related quality of life (P<0.05). During a median follow-up of 6.2 years, there were 1055 CKD progression events, 841 cardiovascular events, and 694 deaths. Significantly higher crude rates of CKD progression, incident cardiovascular events, and all-cause death were observed among participants with low health-related quality of life in all subscales (P<0.05). In fully adjusted models, low physical component summary, effects, and symptoms subscales were independently associated with a higher risk of incident cardiovascular events and death, whereas low mental component summary was independently associated with a higher risk of death (P<0.05). Low health-related quality of life was not associated with CKD progression., Conclusions: Low health-related quality of life across several subscales was independently associated with a higher risk of incident cardiovascular events and death but not associated with CKD progression., (Copyright © 2016 by the American Society of Nephrology.)

Background and Objectives: Disorders of mineral metabolism are more common in African Americans with CKD than in European Americans with CKD. Previous studies have focused on the differences in mineral metabolism by self-reported race, making it difficult to delineate the importance of environmental compared with biologic factors., Design, Setting, Participants, & Measurements: In a cross-sectional analysis of 3013 participants of the Chronic Renal Insufficiency Cohort study with complete data, we compared markers of mineral metabolism (phosphorus, calcium, alkaline phosphatase, parathyroid hormone, fibroblast growth factor 23, and urine calcium and phosphorus excretion) in European Americans versus African Americans and separately, across quartiles of genetic African ancestry in African Americans (n=1490)., Results: Compared with European Americans, African Americans had higher blood concentrations of phosphorus, alkaline phosphatase, fibroblast growth factor 23, and parathyroid hormone, lower 24-hour urinary excretion of calcium and phosphorus, and lower urinary fractional excretion of calcium and phosphorus at baseline (P<0.001 for all). Among African Americans, a higher percentage of African ancestry was associated with lower 24-hour urinary excretion of phosphorus (Ptrend<0.01) in unadjusted analyses. In linear regression models adjusted for socio-demographic characteristics, kidney function, serum phosphorus, and dietary phosphorus intake, higher percentage of African ancestry was significantly associated with lower 24-hour urinary phosphorus excretion (each 10% higher African ancestry was associated with 39.6 mg lower 24-hour urinary phosphorus, P<0.001) and fractional excretion of phosphorus (each 10% higher African ancestry was associated with an absolute 1.1% lower fractional excretion of phosphorus, P=0.01)., Conclusions: A higher percentage of African ancestry was independently associated with lower 24-hour urinary phosphorus excretion and lower fractional excretion of phosphorus among African Americans with CKD. These findings suggest that genetic variability might contribute to racial differences in urinary phosphorus excretion in CKD., (Copyright © 2016 by the American Society of Nephrology.)

Background: In the general population, the association between uninsurance and mortality is well established. We sought to evaluate the association of health insurance status with mortality among working-age participants with albuminuria in the Third National Health and Nutrition Examination Survey, 1988-1994 (NHANES III)., Methods: We used data from non-elderly adult participants (18-64) of NHANES III (1988-1994), a nationally representative study of the US civilian, noninstitutionalized population, who provided information on insurance and who had albuminuria, defined as a urine albumin-to-creatinine ratio [UACR] ≥ 30 mg/g and their subsequent mortality to December 31, 2006. Cox proportional hazards models were used to determine associations between insurance status and all-cause mortality and cardiovascular mortality in patients with CKD while adjusting in a stepwise fashion for sociodemographic factors, co-morbidities, and co-morbidity severity/control covariates., Results: In our sample of individuals with albuminuria (n = 903), mean estimated glomerular filtration rate (eGFR) was 101.6 ml/min/1.73 m(2) with 4.7 % with an eGFR <60. Approximately 15 % of the sample was uninsured, 18 % had public insurance and 67 % had private insurance. Compared to individuals with private insurance, those with public insurance or no insurance were significantly more likely to be a racial or ethnic minority, to have income <200 % below the federal poverty level, to have less than high school education; and they were less likely to be married and to report good or excellent health, all p < 0.05. Being uninsured or having public insurance was associated with increased all-cause mortality in the fully adjusted model (HR 2.97 and 3.65, respectively, p < 0.05). There was no significant relationship between insurance status and cardiovascular mortality., Conclusions: In a nationally representative sample of individuals with albuminuria, uninsurance and public insurance were associated with increased mortality compared to the private insurance even after controlling for sociodemographic, health status, and health care variables. Improving access to care and the quality of care received may potentially reduce mortality in individuals with evidence of early CKD.

Patients with chronic kidney disease (CKD) experience other diseases such as cardiovascular disease (CVD) and retinopathy. The purpose of this study was to assess whether retinopathy predicts future CVD events in a subgroup of the participants of the Chronic Renal Insufficiency Cohort (CRIC) study. In this ancillary investigation, 2,605 participants of the CRIC study were invited to participate, and nonmydriatic fundus photographs were obtained in 1,936 subjects. Using standard protocols, presence and severity of retinopathy (diabetic, hypertensive, or other) and vessel diameter caliber were assessed at a central photograph reading center by trained graders masked to study participant's information. Patients with a self-reported history of cardiovascular disease were excluded. Incident CVD events were adjudicated using medical records. Kidney function measurements, traditional and nontraditional risk factors, for CVD were obtained. Presence and severity of retinopathy were associated with increased risk of development of any CVD in this population of CKD patients, and these associations persisted after adjustment for traditional risk factors for CVD. We also found a direct relation between increased venular diameter and risk of development of CVD; however, the relation was not statistically significant after adjustment for traditional risk factors. In conclusion, the presence of retinopathy was associated with future CVD events, suggesting that retinovascular pathology may be indicative of macrovascular disease even after adjustment for renal dysfunction and traditional CVD risk factors. Assessment of retinal morphology may be valuable in assessing risk of CVD in patients with CKD, both clinically and in research settings., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The Chronic Renal Insufficiency Cohort (CRIC) Study is a United States multicenter, prospective study of racially and ethnically diverse patients with CKD. Although the original aims of the study were to identify novel predictors of CKD progression and to elucidate the risk and manifestations of cardiovascular disease among nearly 4000 individuals with CKD, the CRIC Study has evolved into a national resource for investigation of a broad spectrum of CKD-related topics. The study has produced >90 published scientific articles, promoted many young investigative careers in nephrology, and fostered international collaborations focused on understanding the global burden of CKD. The third phase of the CRIC Study will complete enrollment of 1500 additional study participants in 2015 and is designed to answer questions regarding morbidity and mortality in mild-to-moderate CKD and to assess the burden of CKD in older persons. This review highlights some of the salient findings of the CRIC Study in the areas of race and ethnicity, CKD progression, CKD and cognition, and cardiovascular disease outcomes; it also outlines the ongoing and forthcoming opportunities for the global nephrology community to enhance its understanding of CKD and related complications through the study., (Copyright © 2015 by the American Society of Nephrology.)

Background and Objectives: The prevalence of ESRD among Hispanics/Latinos is 2-fold higher than in non-Hispanic whites. However, little is known about the prevalence of earlier stages of CKD among Hispanics/Latinos. This study estimated the prevalence of CKD in US Hispanics/Latinos., Design, Setting, Participants, & Measurements: This was a cross-sectional study of 15,161 US Hispanic/Latino adults of Cuban, Dominican, Mexican, Puerto Rican, Central American, and South American backgrounds enrolled in the multicenter, prospective, population-based Hispanic Community Health Study/Study of Latinos (HCHS/SOL). In addition, the prevalence of CKD in Hispanics/Latinos was compared with other racial/ethnic groups in the 2007-2010 National Health and Nutrition Examination Survey (NHANES). Prevalent CKD was defined as an eGFR <60 ml/min per 1.73 m(2) (estimated with the 2012 Chronic Kidney Disease Epidemiology Collaboration eGFR creatinine-cystatin C equation) or albuminuria based on sex-specific cut points determined at a single point in time., Results: The overall prevalence of CKD among Hispanics/Latinos was 13.7%. Among women, the prevalence of CKD was 13.0%, and it was lowest in persons with South American background (7.4%) and highest (16.6%) in persons with Puerto Rican background. In men, the prevalence of CKD was 15.3%, and it was lowest (11.2%) in persons with South American background and highest in those who identified their Hispanic background as "other" (16.0%). The overall prevalence of CKD was similar in HCHS/SOL compared with non-Hispanic whites in NHANES. However, prevalence was higher in HCHS/SOL men and lower in HCHS/SOL women versus NHANES non-Hispanic whites. Low income, diabetes mellitus, hypertension, and cardiovascular disease were each significantly associated with higher risk of CKD., Conclusions: Among US Hispanic/Latino adults, there was significant variation in CKD prevalence among Hispanic/Latino background groups, and CKD was associated with established cardiovascular risk factors., (Copyright © 2015 by the American Society of Nephrology.)

Background: Periodontal disease is associated with increased mortality in the general population, however its prognostic significance in chronic kidney disease (CKD) is not known. We evaluated the joint effect of periodontal disease and CKD on all-cause and cardiovascular mortality., Methods: Prospective observational study of 10,755 adult participants in the National Health and Nutrition Examination Survey, 1988-1994 (NHANES III). CKD was defined as estimated glomerular filtration rate < 60 ml/minute/1.73 m(2) or albumin-to-creatinine ratio ≥ 30 mg/g. Periodontal disease was defined as moderate (> 4 mm attachment loss in ≥ 2 mesial sites or 5 mm pocket depth in ≥ 2 mesial sites), or severe (> 6 mm attachment loss in ≥ 2 mesial sites and > 5 mm pocket depth in ≥ 1 mesial site). All-cause and cardiovascular mortality were evaluated using Cox proportional hazards models., Results: There were 1,813 deaths over a median follow-up of 14 years. In multivariate analyses, as compared to participants with neither periodontal disease nor CKD, those with periodontal disease only or CKD only had increased all-cause mortality (HR 1.39; 95 % CI, 1.06-1.81 and 1.55; 1.30-1.84, respectively). The presence of both periodontal disease and CKD was associated with HR (95 % CI) 2.07 (1.65-2.59) for all-cause mortality, and 2.11 (1.52-2.94) for cardiovascular mortality. We found no evidence of multiplicativity or additivity between periodontal disease and CKD. In stratified analyses limited to individuals with CKD, periodontal disease (vs. not) was associated with adjusted HR (95 % CI) 1.35 (1.04-1.76) for all-cause, and 1.36 (0.95-1.95) for cardiovascular mortality., Conclusions: These findings confirm the well-established association between periodontal disease and increased mortality in the general population, and provide new evidence of this association among individuals with CKD.

In the U.S., more than 400,000 individuals with end-stage renal disease (ESRD) require hemodialysis (HD) for renal replacement therapy. ESRD patients experience a high burden of morbidity, mortality, resource utilization, and poor quality of life (QOL). Under current care models, ESRD patients receive fragmented care from multiple providers at multiple locations. The Patient-Centered Medical Home (PCMH) is a team approach, providing coordinated care across the healthcare continuum. While this model has shown some early benefits for complex chronic diseases such as diabetes, it has not been applied to HD patients. This study is a non-randomized quasi-experimental intervention trial implementing a Patient-Centered Medical Home for Kidney Disease (PCMH-KD). The PCMH-KD extends the existing dialysis care team (comprised of a nephrologist, dialysis nurse, dialysis technician, social worker, and dietitian) by adding a general internist, pharmacist, nurse coordinator, and a community health worker, all of whom will see the patients together, and separately, as needed. The primary goal is to implement a comprehensive, multidisciplinary care team to improve care coordination, quality of life, and healthcare use for HD patients. Approximately 240 patients will be recruited from two sites; a non-profit university-affiliated dialysis center and an independent for-profit dialysis center. Outcomes include (i) patient-reported outcomes, including QOL and satisfaction; (ii) clinical outcomes, including blood pressure and diet; (iii) healthcare use, including emergency room visits and hospitalizations; and (iv) staff perceptions. Given the significant burden that patients with ESRD on HD experience, enhanced care coordination provides an opportunity to reduce this burden and improve QOL., (Copyright © 2015 Elsevier Inc. All rights reserved.)

High-sensitivity troponin T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) strongly predict heart failure (HF) in the general population. However, the interpretation of levels of these biomarkers as predictors of HF is uncertain among patients with CKD. Here, we investigated whether hsTnT and NT-proBNP are associated with incident HF among patients with CKD. In a prospective cohort analysis, we studied 3483 people with CKD in the Chronic Renal Insufficiency Cohort (CRIC) Study recruited from June of 2003 to August of 2008 who were free of HF at baseline. We used Cox regression to examine the association of baseline levels of hsTnT and NT-proBNP with incident HF after adjustment for demographic factors, traditional cardiovascular risk factors, markers of kidney disease, pertinent medication use, and mineral metabolism markers. At baseline, hsTnT levels ranged from ≤5.0 to 738.7 pg/ml, and NT-proBNP levels ranged from ≤5 to 35,000 pg/ml. Compared with those who had undetectable hsTnT, participants in the highest quartile (>26.5 pg/ml) had a significantly higher rate of HF (hazard ratio, 4.77; 95% confidence interval, 2.49 to 9.14). Similarly, compared with those in the lowest NT-proBNP quintile (<47.6 pg/ml), participants in the highest quintile (>433.0 pg/ml) experienced a substantially higher rate of HF (hazard ratio, 9.57; 95% confidence interval, 4.40 to 20.83) [corrected]. In conclusion, hsTnT and NT-proBNP were strongly associated with incident HF among a diverse cohort of individuals with mild to severe CKD. Elevations in these biomarkers may indicate subclinical changes in volume and myocardial stress that subsequently contribute to clinical HF., (Copyright © 2015 by the American Society of Nephrology.)

Background: In general populations, healthy lifestyle is associated with fewer adverse outcomes. We estimated the degree to which adherence to a healthy lifestyle decreases the risk of renal and cardiovascular events among adults with chronic kidney disease (CKD)., Study Design: Prospective cohort., Setting & Participants: 3,006 adults enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study., Predictors: 4 lifestyle factors (regular physical activity, body mass index [BMI] of 20-<25kg/m(2), nonsmoking, and "healthy diet"), individually and in combination., Outcomes: CKD progression (50% decrease in estimated glomerular filtration rate or end-stage renal disease), atherosclerotic events (myocardial infarction, stroke, or peripheral arterial disease), and all-cause mortality., Measurements: Multivariable-adjusted Cox proportional hazards., Results: During a median follow-up of 4 years, we observed 726 CKD progression events, 355 atherosclerotic events, and 437 deaths. BMI≥25kg/m(2) and nonsmoking were associated with reduced risk of CKD progression (HRs of 0.75 [95% CI, 0.58-0.97] and 0.61 [95% CI, 0.45-0.82] for BMIs of 25 to <30 and ≥30kg/m(2), respectively, versus 20 to <25kg/m(2); HR for nonsmoking of 0.68 [95% CI, 0.55-0.84] compared to the current smoker reference group) and reduced risk of atherosclerotic events (HRs of 0.67 [95% CI, 0.46-0.96] for BMI of 25-<30 vs 20-<25kg/m(2) and 0.55 [95% CI, 0.40-0.75] vs current smoker). Factors associated with reduced all-cause mortality were regular physical activity (HR, 0.64 [95% CI, 0.52-0.79] vs inactive), BMI≥30kg/m(2) (HR, 0.64 [95% CI, 0.43-0.96] vs 20-<25kg/m(2)), and nonsmoking (HR, 0.45 [95% CI, 0.34-0.60] vs current smoker). BMI<20kg/m(2) was associated with increased all-cause mortality risk (HR, 2.11 [95% CI, 1.13-3.93] vs 20-<25kg/m(2)). Adherence to all 4 lifestyle factors was associated with a 68% lower risk of all-cause mortality compared to adherence to no lifestyle factors (HR, 0.32; 95% CI, 0.11-0.89)., Limitations: Lifestyle factors were measured only once., Conclusions: Regular physical activity, nonsmoking, and BMI≥25kg/m(2) were associated with lower risk of adverse outcomes in this cohort of individuals with CKD., (Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Previous reports of the longitudinal association between achieved blood pressure (BP) and end-stage renal disease (ESRD) among patients with chronic kidney disease (CKD) have not incorporated time-updated BP with appropriate covariate adjustment., Objective: To assess the association between baseline and time-updated systolic blood pressure (SBP) with CKD progression., Design: Observational, prospective cohort study. (ClinicalTrials.gov: NCT00304148)., Setting: 7 U.S. clinical centers., Patients: Patients in the Chronic Renal Insufficiency Cohort Study (n = 3708) followed for a median of 5.7 years (25th to 75th percentile, 4.6 to 6.7 years)., Measurements: The mean of 3 seated SBP measurements made up the visit-specific SBP. Time-updated SBP was the mean of that and all previous visits. Outcomes were ESRD and the composite end point of ESRD or halving of the estimated glomerular filtration rate. Analyses investigating baseline and time-updated SBP used Cox proportional hazards models and marginal structural models, respectively., Results: Systolic blood pressure was 130 mm Hg or greater at all visits in 19.2% of patients. The hazard ratio for ESRD among patients with SBP of 130 to 139 mm Hg, compared with SBP less than 120 mm Hg, was 1.46 (95% CI, 1.13 to 1.88) using only baseline data and 2.37 (CI, 1.48 to 3.80) using time-updated data. Among patients with SBP of 140 mm Hg or greater, corresponding hazard ratios were 1.46 (CI, 1.18 to 1.88) and 3.37 (CI, 2.26 to 5.03) for models using only baseline data and those using time-updated data, respectively., Limitation: Blood pressure was measured once annually, and the cohort was not a random sample., Conclusion: Time-updated SBP greater than 130 mm Hg was more strongly associated with CKD progression than analyses based on baseline SBP., Primary Funding Source: National Institute of Diabetes and Digestive and Kidney Diseases.

Objectives: To determine the association between cognition and levels of cystatin C in persons with chronic kidney disease (CKD)., Design: Prospective observational study., Setting: Chronic Renal Insufficiency Cohort Cognitive Study., Participants: Individuals with a baseline cognitive assessment completed at the same visit as serum cystatin C measurement (N = 821; mean age 64.9, 50.6% male, 48.6% white)., Measurements: Levels of serum cystatin C were categorized into tertiles; cognitive function was assessed using six neuropsychological tests. Scores on these tests were compared across tertiles of cystatin C using linear regression and logistic regression to examine the association between cystatin C level and cognitive performance (1 standard deviation difference from the mean)., Results: After multivariable adjustment for age, race, education, and medical comorbidities in linear models, higher levels of cystatin C were associated with worse cognition on the modified Mini-Mental State Examination, Buschke Delayed Recall, Trail-Making Test Part (Trails) A and Part B, and Boston Naming (P < .05 for all). This association remained statistically significant for Buschke Delayed Recall (P = .01) and Trails A (P = .03) after additional adjustment for estimated glomerular filtration rate (eGFR). The highest tertile of cystatin C was associated with greater likelihood of poor performance on Trails A (odds ratio (OR) = 2.17, 95% confidence interval (CI) = 1.16-4.06), Trails B (OR = 1.89, 95% CI = 1.09-3.27), and Boston Naming (OR = 1.85, 95% CI = 1.07-3.19) than the lowest tertile after multivariate adjustment in logistic models., Conclusion: In individuals with CKD, higher serum cystatin C levels were associated with worse cognition and greater likelihood of poor cognitive performance on attention, executive function, and naming. Cystatin C is a marker of cognitive impairment and may be associated with cognition independent of eGFR., (© 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.)

Background: Chronic kidney disease is associated with an increased risk of heart failure (HF). We aimed to evaluate the role of large artery stiffness, brachial, and central blood pressure as predictors of incident hospitalized HF in the Chronic Renal Insufficiency Cohort (CRIC), a multiethnic, multicenter prospective observational study of patients with chronic kidney disease., Methods and Results: We studied 2602 participants who were free of HF at baseline. Carotid-femoral pulse wave velocity (CF-PWV; the gold standard index of large artery stiffness), brachial, and central pressures (estimated via radial tonometry and a generalized transfer function) were assessed at baseline. Participants were prospectively followed up to assess the development of new-onset hospitalized HF. During 3.5 years of follow-up, 154 participants had a first hospital admission for HF. CF-PWV was a significant independent predictor of incident hospitalized HF. When compared with the lowest tertile, the hazard ratios among subjects in the middle and top CF-PWV tertiles were 2.33 (95% confidence interval, 1.37-3.97; P=0.002) and 5.24 (95% confidence interval, 3.22-8.53; P<0.0001), respectively. After adjustment for multiple confounders, the hazard ratios for the middle and top CF-PWV tertiles were 1.95 (95% confidence interval, 0.92-4.13; P=0.079) and 3.01 (95% confidence interval, 1.45-6.26; P=0.003), respectively. Brachial systolic and pulse pressure were also independently associated with incident hospitalized HF, whereas central pressures were less consistently associated with this end point. The association between CF-PWV and incident HF persisted after adjustment for systolic blood pressure., Conclusions: Large artery stiffness is an independent predictor of incident HF in chronic kidney disease, an association with strong biological plausibility given the known effects of large artery stiffening of left ventricular pulsatile load., (© 2014 American Heart Association, Inc.)

Low health-related quality of life (HRQOL) has been associated with increased risk for hospitalization and death in ESRD. However, the relationship of HRQOL with outcomes in predialysis CKD is not well understood. We evaluated the association between HRQOL and renal and cardiovascular (CV) outcomes in 1091 African Americans with hypertensive CKD enrolled in the African American Study of Kidney Disease and Hypertension (AASK) trial and cohort studies. Outcomes included CKD progression (doubling of serum creatinine/ESRD), CV events/CV death, and a composite of CKD progression or death from any cause (CKD progression/death). We assessed HRQOL, including mental health composite (MHC) and physical health composite (PHC), using the Short Form-36 survey. Cox regression analyses were used to assess the relationship between outcomes and five-point decrements in MHC and PHC scores using measurements at baseline, at the most recent annual visit (time-varying), or averaged from baseline to the most recent visit (cumulative). During approximately 10 years of follow-up, lower mean PHC score was associated with increased risk of CV events/CV death and CKD progression/death across all analytic approaches, but only time-varying and cumulative decrements were associated with CKD progression. Similarly, lower mean MHC score was associated with increased risk of CV events/CV death regardless of analytic approach, while only time-varying and cumulative decrements in mean MHC score was associated with CKD progression and CKD progression or death. In conclusion, lower HRQOL is associated with a range of adverse outcomes in African Americans with hypertensive CKD., (Copyright © 2014 by the American Society of Nephrology.)

Background: Retinopathy is associated with increased mortality risk in general populations. We evaluated the joint effect of retinopathy and chronic kidney disease (CKD) on mortality in a representative sample of U.S. adults., Study Design: Prospective cohort study., Setting & Participants: 7,640 adults from NHANES (National Health and Nutrition Examination Survey) 1988-1994 with mortality linkage through December 31, 2006., Predictors: CKD, defined as low estimated glomerular filtration rate (<60 mL/min/1.73 m2) or albuminuria (urine protein-creatinine ratio ≥30 mg/g), and retinopathy, defined as the presence of microaneurysms, hemorrhages, exudates, microvascular abnormalities, or other evidence of diabetic retinopathy by fundus photograph., Outcomes: All-cause and cardiovascular mortality., Measurements: Multivariable-adjusted Cox proportional hazards., Results: Overall, 4.6% of participants had retinopathy and 15% had CKD. Mean age was 56 years, 53% were women, and 81% were non-Hispanic whites. The prevalence of retinopathy in patients with CKD was 11%. We identified 2,634 deaths during 14.5 years' follow-up. In multivariable analyses, compared with individuals with neither CKD nor retinopathy, HRs for all-cause mortality were 1.02 (95% CI, 0.75-1.38), 1.52 (95% CI, 1.35-1.72), and 2.39 (95% CI, 1.77-3.22) for individuals with retinopathy only, those with CKD only, and those with both CKD and retinopathy, respectively. Corresponding HRs for cardiovascular mortality were 0.96 (95% CI, 0.50-1.84), 1.72 (95% CI, 1.47-2.00), and 2.96 (95% CI, 2.11-4.15), respectively. There was a significant synergistic interaction between retinopathy and CKD on all-cause mortality (P=0.04)., Limitations: The presence of retinopathy was evaluated only once. Small sample size of some of the subpopulations studied., Conclusions: In the presence of CKD, retinopathy is a strong predictor of mortality in this adult population., (Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background and Objectives: Retinal abnormalities may be associated with changes in the renal vasculature. This study assessed the association between retinopathy and progression of kidney disease in participants of the Chronic Renal Insufficiency Cohort (CRIC) study., Design, Setting, Participants, & Measurements: This was a prospective study in which patients with CKD enrolled in CRIC had nonmydriatic fundus photographs of both eyes. All CRIC participants in six clinical sites in which fundus cameras were deployed were offered participation. Photographs were reviewed at a reading center. The presence and severity of retinopathy and vessel calibers were assessed using standard protocols by graders masked to clinical information. The associations of retinal features with changes in eGFR and the need for RRT (ESRD) were assessed., Results: Retinal images and renal progression outcomes were obtained from 1852 of the 2605 participants (71.1%) approached. During follow-up (median 2.3 years), 152 participants (8.2%) developed ESRD. Presence and severity of retinopathy at baseline were strongly associated with the risk of subsequent progression to ESRD and reductions in eGFR in unadjusted analyses. For example, participants with retinopathy were 4.4 times (95% confidence interval [95% CI], 3.12 to 6.31) more likely to develop ESRD than those without retinopathy (P<0.001). However, this association was not statistically significant after adjustment for initial eGFR and 24-hour proteinuria. Venular and arteriolar diameter calibers were not associated with ESRD or eGFR decline. The results showed a nonlinear relationship between mean ratio of arteriole/vein calibers and the risk of progression to ESRD; participants within the fourth arteriole/vein ratio quartile were 3.11 times (95% CI, 1.51 to 6.40) more likely to develop ESRD than those in the first quartile (P<0.001)., Conclusions: The presence and severity of retinopathy were not associated with ESRD and decline in eGFR after taking into account established risk factors., (Copyright © 2014 by the American Society of Nephrology.)

The National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (NKF-KDOQI) guideline for evaluation, classification, and stratification of chronic kidney disease (CKD) was published in 2002. The KDOQI guideline was well accepted by the medical and public health communities, but concerns and criticisms arose as new evidence became available since the publication of the original guidelines. KDIGO (Kidney Disease: Improving Global Outcomes) recently published an updated guideline to clarify the definition and classification of CKD and to update recommendations for the evaluation and management of individuals with CKD based on new evidence published since 2002. The primary recommendations were to retain the current definition of CKD based on decreased glomerular filtration rate or markers of kidney damage for 3 months or more and to include the cause of kidney disease and level of albuminuria, as well as level of glomerular filtration rate, for CKD classification. NKF-KDOQI convened a work group to write a commentary on the KDIGO guideline in order to assist US practitioners in interpreting the KDIGO guideline and determining its applicability within their own practices. Overall, the commentary work group agreed with most of the recommendations contained in the KDIGO guidelines, particularly the recommendations regarding the definition and classification of CKD. However, there were some concerns about incorporating the cause of disease into CKD classification, in addition to certain recommendations for evaluation and management., (Copyright © 2014. Published by Elsevier Inc.)

Background: Epigenetic mechanisms may be important in the progression of chronic kidney disease (CKD)., Methods: We studied the genome-wide DNA methylation pattern associated with rapid loss of kidney function using the Infinium HumanMethylation 450 K BeadChip in 40 Chronic Renal Insufficiency (CRIC) study participants (n = 3939) with the highest and lowest rates of decline in estimated glomerular filtration rate., Results: The mean eGFR slope was 2.2 (1.4) and -5.1 (1.2) mL/min/1.73 m(2) in the stable kidney function group and the rapid progression group, respectively. CpG islands in NPHP4, IQSEC1 and TCF3 were hypermethylated to a larger extent in subjects with stable kidney function (P-values of 7.8E-05 to 9.5E-05). These genes are involved in pathways known to promote the epithelial to mesenchymal transition and renal fibrosis. Other CKD-related genes that were differentially methylated are NOS3, NFKBIL2, CLU, NFKBIB, TGFB3 and TGFBI, which are involved in oxidative stress and inflammatory pathways (P-values of 4.5E-03 to 0.046). Pathway analysis using Ingenuity Pathway Analysis showed that gene networks related to cell signaling, carbohydrate metabolism and human behavior are epigenetically regulated in CKD., Conclusions: Epigenetic modifications may be important in determining the rate of loss of kidney function in patients with established CKD.

To evaluate the association between haemoglobinuria and chronic kidney disease (CKD) in sickle cell anaemia (SCA), we analysed 356 adult haemoglobin SS or Sβ(o) thalassaemia patients from the University of Illinois at Chicago (UIC) and 439 from the multi-centre Walk-Treatment of Pulmonary Hypertension and Sickle Cell Disease with Sildenafil Therapy (Walk-PHaSST) cohort. CKD was classified according to National Kidney Foundation Kidney Disease Outcomes Quality Initiatives guidelines. Haemoglobinuria, defined as positive haem on urine dipstick with absent red blood cells on microscopy, was confirmed by enzyme-linked immunosorbent assay in a subset of patients. The prevalence of CKD was 58% in the UIC cohort and 54% in the Walk-PHaSST cohort, and haemoglobinuria was observed in 36% and 20% of the patients, respectively. Pathway analysis in both cohorts indicated an independent association of lactate dehydrogenase with haemoglobinuria and, in turn, independent associations of haemoglobinuria and age with CKD (P < 0·0001). After a median of 32 months of follow-up in the UIC cohort, haemoglobinuria was associated with progression of CKD [halving of estimated glomerular filtration rate or requirement for dialysis; Hazard ratio (HR) 13·9, 95% confidence interval (CI) 1·7-113·2, P = 0·0012] and increasing albuminuria (HR 3·1, 95% CI: 1·3-7·7; logrank P = 0·0035). In conclusion haemoglobinuria is common in SCA and is associated with CKD, consistent with a role for intravascular haemolysis in the pathogenesis of renal dysfunction in SCA., (© 2013 John Wiley & Sons Ltd.)

Background: Various indicators of progression of chronic kidney disease (CKD) have been used as outcomes in clinical research studies. The effect of using varying measures on the association of risk factors with CKD progression has not been well characterized., Study Design: Prospective cohort study., Setting & Participants: The Chronic Renal Insufficiency Cohort (CRIC) Study (N=3,939) enrolled men and women with mild to moderate CKD, 48% of whom had diabetes and 42% were self-reported black race., Predictors: Age, race, sex, diabetes, baseline estimated glomerular filtration rate (eGFR), proteinuria, and other established CKD risk factors., Outcomes: Death, end-stage renal disease (ESRD), and eGFR events, including: (1) eGFR halving, (2) eGFR<15mL/min/1.73m(2), (3) eGFR halving and <15mL/min/1.73m(2), (4) eGFR decrease of 20mL/min/1.73m(2), (5) eGFR halving or decrease of 20mL/min/1.73m(2), and (6) eGFR decrease of 25% and change in CKD stage., Results: Mean entry eGFR was 44.9mL/min/1.73m(2). Annual rates of death, ESRD, and eGFR halving were 2.5%, 4.0%, and 6.1%, respectively, during an average follow-up of 5.4 years. Associations between risk factors and ESRD and eGFR events were similar across different definitions. However, these associations were substantially different from those with death. HRs for ESRD, eGFR halving, and death in the highest compared to the lowest proteinuria category were 11.83 (95% CI, 8.40-16.65), 11.19 (95% CI, 8.53-14.68), and 1.47 (95% CI, 1.10-1.96), respectively., Limitations: Participants may not be representative of the entire CKD population., Conclusions: Using ESRD or eGFR events, but not death, in the definition of kidney disease outcomes is appropriate in follow-up studies to identify risk factors for CKD progression., (Copyright © 2014 National Kidney Foundation, Inc. All rights reserved.)

An elevated level of fibroblast growth factor-23 (FGF-23) is the earliest abnormality of mineral metabolism in CKD. High FGF-23 levels promote left ventricular hypertrophy but not coronary artery calcification. We used survival analysis to determine whether elevated FGF-23 is associated with greater risk of adjudicated congestive heart failure (CHF) and atherosclerotic events (myocardial infarction, stroke, and peripheral vascular disease) in a prospective cohort of 3860 participants with CKD stages 2-4 (baseline estimated GFR [eGFR], 44±15 ml/min per 1.73 m(2)). During a median follow-up of 3.7 years, 360 participants were hospitalized for CHF (27 events/1000 person-years) and 287 had an atherosclerotic event (22 events/1000 person-years). After adjustment for demographic characteristics, kidney function, traditional cardiovascular risk factors, and medications, higher FGF-23 was independently associated with graded risk of CHF (hazard ratio [HR], 1.45 per doubling [95% confidence interval (CI), 1.28 to 1.65]; HR for highest versus lowest quartile, 2.98 [95% CI, 1.97 to 4.52]) and atherosclerotic events (HR per doubling, 1.24 [95% CI, 1.09 to 1.40]; HR for highest versus lowest quartile, 1.76 [95% CI, 1.20 to 2.59]). Elevated FGF-23 was associated more strongly with CHF than with atherosclerotic events (P=0.02), and uniformly was associated with greater risk of CHF events across subgroups stratified by eGFR, proteinuria, prior heart disease, diabetes, BP control, anemia, sodium intake, income, fat-free mass, left ventricular mass index, and ejection fraction. Thus, higher FGF-23 is independently associated with greater risk of cardiovascular events, particularly CHF, in patients with CKD stages 2-4.

Background: Low health literacy in the general population is associated with increased risk of death and hospitalization. The evaluation of health literacy in individuals with predialysis chronic kidney disease (CKD) is limited., Methods: We conducted a cross-sectional study to evaluate the associations of limited health literacy with kidney function and cardiovascular disease (CVD) risk factors in 2,340 non-Hispanic (NH) Whites and Blacks aged 21 - 74 years with mild-to-moderate CKD. Limited health literacy was defined as a Short Test of Functional Health Literacy in Adults (STOFHLA) score ≤ 22. Outcomes evaluated included estimated glomerular filtration rate (eGFR), 24-hour urine protein excretion, and CVD risk factors., Results: The prevalence of limited health literacy was 28% in NH-Blacks and 5% in NH-Whites. Compared with participants with adequate health literacy, those with limited health literacy were more likely to have lower eGFR (34 vs. 42 mL/min/1.73 m2); higher urine protein/24-hours (0.31 vs. 0.15 g); and higher self-reported CVD (61 vs. 37%); and were less likely to have BP < 130/80 mmHg (51 vs. 58%); p ≤ 0.01 for each comparison. After adjustment, limited health literacy was associated with self-reported CVD (OR 1.51, 95% CI 1.13 - 2.03) and lower eGFR (β -2.47, p = 0.03)., Conclusion: In this CKD cohort, limited health literacy was highly prevalent, especially among NH-Blacks, and it was associated with lower eGFR and a less favorable CVD risk factor profile. Further studies are needed to better understand these associations and inform the development of health literacy interventions among individuals with CKD.

Background: Among patients in the United States with chronic kidney disease, black patients are at increased risk for end-stage renal disease, as compared with white patients., Methods: In two studies, we examined the effects of variants in the gene encoding apolipoprotein L1 (APOL1) on the progression of chronic kidney disease. In the African American Study of Kidney Disease and Hypertension (AASK), we evaluated 693 black patients with chronic kidney disease attributed to hypertension. In the Chronic Renal Insufficiency Cohort (CRIC) study, we evaluated 2955 white patients and black patients with chronic kidney disease (46% of whom had diabetes) according to whether they had 2 copies of high-risk APOL1 variants (APOL1 high-risk group) or 0 or 1 copy (APOL1 low-risk group). In the AASK study, the primary outcome was a composite of end-stage renal disease or a doubling of the serum creatinine level. In the CRIC study, the primary outcomes were the slope in the estimated glomerular filtration rate (eGFR) and the composite of end-stage renal disease or a reduction of 50% in the eGFR from baseline., Results: In the AASK study, the primary outcome occurred in 58.1% of the patients in the APOL1 high-risk group and in 36.6% of those in the APOL1 low-risk group (hazard ratio in the high-risk group, 1.88; P<0.001). There was no interaction between APOL1 status and trial interventions or the presence of baseline proteinuria. In the CRIC study, black patients in the APOL1 high-risk group had a more rapid decline in the eGFR and a higher risk of the composite renal outcome than did white patients, among those with diabetes and those without diabetes (P<0.001 for all comparisons)., Conclusions: Renal risk variants in APOL1 were associated with the higher rates of end-stage renal disease and progression of chronic kidney disease that were observed in black patients as compared with white patients, regardless of diabetes status. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.).

Background: Cardiac troponin T is independently associated with cardiovascular events and mortality in patients with chronic kidney disease (CKD). Serum levels of high sensitivity cardiac troponin T (hs-TnT) reflect subclinical myocardial injury in ambulatory patients. We sought to determine the distribution and predictors of hs-TnT in CKD patients without overt cardiovascular disease (CVD)., Methods: We studied 2464 participants within the multi-ethnic Chronic Renal Insufficiency Cohort (CRIC) who did not have self-reported CVD. We considered renal and non-renal factors as potential determinants of hs-TnT, including demographics, comorbidities, left ventricular (LV) mass, serologic factors, estimated glomerular filtration rate (eGFR) and albumin to creatinine ratio., Results: Hs-TnT was detectable in 81% of subjects, and the median (IQR) hs-TnT was 9.4 pg/ml (4.3-18.3). Analysis was performed using Tobit regression, adjusting for renal and non-renal factors. After adjustment, lower eGFR was associated with higher expected hs-TnT; participants with eGFR < 30 ml/min/1.73 m(2) had 3-fold higher expected hs-TnT compared to subjects with eGFR > 60. Older age, male gender, black race, LV mass, diabetes and higher blood pressure all had strong, independent associations with higher expected hs-TnT., Conclusions: Knowledge of the determinants of hs-TnT in this cohort may guide further research on the pathology of heart disease in patients with CKD and help to stratify sub-groups of CKD patients at higher cardiovascular risk.

Elevated fibroblast growth factor 23 (FGF23) is associated with cardiovascular disease in patients with chronic kidney disease. As a potential mediating mechanism, FGF23 induces left ventricular hypertrophy; however, its role in arterial calcification is less clear. In order to study this, we quantified coronary artery and thoracic aorta calcium by computed tomography in 1501 patients from the Chronic Renal Insufficiency Cohort (CRIC) study within a median of 376 days (interquartile range 331-420 days) of baseline. Baseline plasma FGF23 was not associated with the prevalence or severity of coronary artery calcium after multivariable adjustment. In contrast, higher serum phosphate levels were associated with prevalence and severity of coronary artery calcium, even after adjustment for FGF23. Neither FGF23 nor serum phosphate were consistently associated with thoracic aorta calcium. We could not detect mRNA expression of FGF23 or its coreceptor, klotho, in human or mouse vascular smooth muscle cells, or normal or calcified mouse aorta. Whereas elevated phosphate concentrations induced calcification in vitro, FGF23 had no effect on phosphate uptake or phosphate-induced calcification regardless of phosphate concentration or even in the presence of soluble klotho. Thus, in contrast to serum phosphate, FGF23 is not associated with arterial calcification and does not promote calcification experimentally. Hence, phosphate and FGF23 promote cardiovascular disease through distinct mechanisms.

Background and Objective: Among general populations, a healthy lifestyle has been associated with lower risk of death. This study evaluated this association in individuals with CKD., Design, Setting, Participants, & Measurements: A total of 2288 participants with CKD (estimated GFR < 60 ml/min per 1.73 m(2) or microalbuminuria) in the Third National Health and Nutrition Examination Survey were included. A weighted healthy lifestyle score was calculated (range, -4 to 15, with 15 indicating healthiest lifestyle) on the basis of the multivariable Cox proportional hazards model regression coefficients of the following lifestyle factors: smoking habit, body mass index (BMI), physical activity, and diet. Main outcome was all-cause mortality, ascertained through December 31, 2006., Results: After median follow-up of 13 years, 1319 participants had died. Compared with individuals in the lowest quartile of weighted healthy lifestyle score, adjusted hazard ratios (95% confidence intervals) of all-cause mortality were 0.53 (0.41-0.68), 0.52 (0.42-0.63), and 0.47 (0.38-0.60) for individuals in the second, third, and fourth quartiles, respectively. Mortality increased 30% among individuals with a BMI of 18.5 to <22 kg/m(2) versus 22 to <25 kg/m(2) (P<0.05); decreased mortality was associated with never-smoking versus current smoking (0.54 [0.41-0.70]) and regular versus no physical activity (0.80 [0.65-0.99]). Diet was not significantly associated with mortality., Conclusions: Compared with nonadherence, adherence to a healthy lifestyle was associated with lower all-cause mortality risk in CKD. Examination of individual components of the healthy lifestyle score, with adjustment for other components, suggested that the greatest reduction in all-cause mortality was related to nonsmoking.

Objective: Evaluate the reliability and validity of the Kidney Disease Quality of Life Short Form 36 (KDQOL-36) in Hispanics with mild-to-moderate chronic kidney disease (CKD)., Design: Cross-sectional, Setting: Chronic Renal Insufficiency Cohort Study, Participants: 420 Hispanic (150 English- and 270 Spanish-speakers), and 409 non-Hispanic White individuals, matched by age (mean 57 years), sex (60% male), kidney function (mean estimated glomerular filtration rate 36ml/min/1.73m2), and diabetes (70%)., Methods: To measure construct validity, we selected instruments, comorbidities, and laboratory tests related to at least one KDQOL-36 subscale. Reliability was determined by calculating Cronbach's alpha., Results: Reliability of each KDQOL-36 subscale [SF-12 Physical Component Summary (PCS) and Mental Component Summary (MCS), Symptoms/Problems, Burden of Kidney Disease and Effects of Kidney Disease] was very good (Cronbach's alpha >0.8). Construct validity was supported by expected negative correlation between MCS scores and the Beck Depression Inventory in all three subgroups (r=-0.56 to -0.61, P<.0001). There was inverse correlation between the Symptoms/ Problems subscale and the Patient Symptom Form (r= -0.70 to -0.77, P<.0001). We also found significant, positive correlation between the PCS score and a physical activity survey (r=+0.29 to +0.38, P< or =.003); and between the PCS and MCS scores and the Kansas City Questionnaire (r= +0.31 to +0.64, P<.0001). Reliability and validity were similar across all racial/ethnic groups analyzed separately., Conclusion: Our findings support the use of the KDQOL-36 as a measure of HRQOL in this cohort of US Hispanics with CKD.

The objective of our study was to determine the effects of 2 antihypertensive drug dose schedules (PM dose and add-on dose) on nocturnal blood pressure (BP) in comparison with usual therapy (AM dose) in blacks with hypertensive chronic kidney disease and controlled office BP. In a 3-period, crossover trial, former participants of the African American Study of Kidney Disease were assigned to receive the following 3 regimens, each lasting 6 weeks, presented in random order: AM dose (once-daily antihypertensive medications taken in the morning), PM dose (once-daily antihypertensives taken at bedtime), and add-on dose (once-daily antihypertensives taken in the morning and an additional antihypertensive medication before bedtime [diltiazem 60-120 mg, hydralazine 25 mg, or additional ramipril 5 mg]). Ambulatory BP monitoring was performed at the end of each period. The primary outcome was nocturnal systolic BP. Mean age of the study population (n=147) was 65.4 years, 64% were men, and mean estimated glomerular filtration rate was 44.9 mL/min per 1.73 m(2). At the end of each period, mean (SE) nocturnal systolic BP was 125.6 (1.2) mm Hg in the AM dose, 123.9 (1.2) mm Hg in the PM dose, and 123.5 (1.2) mm Hg in the add-on dose. None of the pairwise differences in nocturnal, 24-hour, and daytime systolic BP was statistically significant. Among blacks with hypertensive chronic kidney disease, neither PM (bedtime) dosing of once-daily antihypertensive nor the addition of drugs taken at bedtime significantly reduced nocturnal BP compared with morning dosing of antihypertensive medications.

Cardiovascular disease is the leading cause of death in patients with chronic kidney disease (CKD). We examined the cross-sectional association between novel risk factors and coronary artery calcium (CAC) measured using electron beam computed tomography or multidetector computed tomography among 2,018 patients with CKD. Using the total Agatston scores, the participants were classified as having no (0), moderate (>0-100), or high (>100) CAC. After adjustment for age, gender, race, study sites, cigarette smoking, previous cardiovascular disease, hypertension, and diabetes, the use of lipid-lowering drugs, body mass index, waist circumference, and cystatin C, several novel risk factors were significantly associated with high CAC. For example, the odds ratios of high CAC associated with 1 SD greater level of risk factors were 1.20 (95% confidence interval 1.04 to 1.38) for serum calcium, 1.21 (95% confidence interval 1.04 to 1.41) for serum phosphate, 0.83 (95% confidence interval 0.71 to 0.97) for log (total parathyroid hormone), 1.21 (95% confidence interval 1.03 to 1.43) for log (homeostasis model assessment-insulin resistance), and 1.23 (95% confidence interval 1.04 to 1.45) for hemoglobin A1c. Additionally, the multivariate-adjusted odds ratio for 1 SD greater level of cystatin C was 1.31 (95% confidence interval 1.14 to 1.50). Serum high-sensitive C-reactive protein, interleukin-6, tumor necrosis factor-α, and homocysteine were not statistically significantly associated with high CAC. In conclusion, these data indicate that abnormal calcium and phosphate metabolism, insulin resistance, and declining kidney function are associated with the prevalence of high CAC, independent of the traditional risk factors in patients with CKD. Additional studies are warranted to examine the causal effect of these risk factors on CAC in patients with CKD., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Illicit drug use has been associated with chronic kidney disease (CKD) in select populations, but it is unknown whether the same association exists in the general population. By using data from the National Health and Nutrition Examination Survey 2005-2008, we conducted a cross-sectional analysis of 5861 adults who were questioned about illicit drug use, including cocaine, methamphetamines, and heroin, during their lifetime. The primary outcome was CKD as defined by an estimated glomerular filtration rate ≤60 mL/min/1.73 m(2) using the Chronic Kidney Disease Epidemiology Collaboration equation or by microalbuminuria. We also examined the association between illicit drug use and blood pressure (BP) ≥120/80, ≥130/85, and ≥140/90 mm Hg. Logistic regression was used to examine the association between illicit drug use and CKD and BP. Mean estimated glomerular filtration rate was similar between illicit drug users and nonusers (100.7 vs 101.4 mL/min/1.73 m(2), P = 0.4), as was albuminuria (5.7 vs 6.0 mg/g creatinine, P = 0.5). Accordingly, illicit drug use was not significantly associated with CKD in logistic regression models (odds ratio [OR], 0.98; confidence interval [CI], 0.75-1.27) after adjusting for other important factors. However, illicit drug users had higher systolic (120 vs 118 mm Hg, P = 0.04) and diastolic BP (73 vs 71 mm Hg, P = 0.0003) compared with nonusers. Cocaine use was independently associated with BP ≥130/85 mm Hg (OR, 1.24; CI, 1.00-1.54), especially when used more during a lifetime (6-49 times; OR, 1.42; CI, 1.06-1.91). In a representative sample of the US population, illicit drug use was not associated with CKD, but cocaine users were more likely to have elevated BP., (Copyright © 2012 Mosby, Inc. All rights reserved.)

Despite the high prevalence and enormous public health implications of chronic kidney disease (CKD), the factors responsible for its development and progression are incompletely understood. To date, only a few studies have attempted to objectively characterize sleep in patients with CKD prior to kidney failure, but emerging evidence suggests a high prevalence of sleep disorders, particularly obstructive sleep apnea. Laboratory and epidemiologic studies have shown that insufficient sleep and poor sleep quality promote the development and exacerbate the severity of 3 important risk factors for CKD, namely hypertension, type 2 diabetes, and obesity. In addition, sleep disturbances might have a direct effect on CKD through chronobiological alterations in the renin-angiotensin-aldosterone system and sympathetic nervous system activation. The negative impact of sleep disorders on vascular compliance and endothelial function also may have a deleterious effect on CKD. Sleep disturbances therefore may represent a novel risk factor for the development and progression of CKD. Optimizing sleep duration and quality and treating sleep disorders may reduce the severity and delay the progression of CKD., (Copyright © 2012 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Despite the large burden of chronic kidney disease (CKD) in Hispanics, this population has been underrepresented in research studies. We describe the recruitment strategies employed by the Hispanic Chronic Renal Insufficiency Cohort Study, which led to the successful enrollment of a large population of Hispanic adults with CKD into a prospective observational cohort study. Recruitment efforts by bilingual staff focused on community clinics with Hispanic providers in high-density Hispanic neighborhoods in Chicago, academic medical centers, and private nephrology practices. Methods of publicizing the study included church meetings, local Hispanic print media, Spanish television and radio stations, and local health fairs. From October 2005 to July 2008, we recruited 327 Hispanics aged 21-74 years with mild-to-moderate CKD as determined by age-specific estimated glomerular filtration rate (eGFR). Of 716 individuals completing a screening visit, 49% did not meet eGFR inclusion criteria and 46% completed a baseline visit. The mean age at enrollment was 57.1 and 67.1% of participants were male. Approximately 75% of enrolled individuals were Mexican American, 15% Puerto Rican, and 10% had other Latin American ancestry. Eighty two percent of participants were Spanish-speakers. Community-based and academic primary care clinics yielded the highest percentage of participants screened (45.9% and 22.4%) and enrolled (38.2% and 24.5%). However, academic and community-based specialty clinics achieved the highest enrollment yield from individuals screened (61.9% to 71.4%). A strategy focused on primary care and nephrology clinics and the use of bilingual recruiters allowed us to overcome barriers to the recruitment of Hispanics with CKD., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Glomerular filtration rate (GFR) is considered the best measure of kidney function, but repeated assessment is not feasible in most research studies., Study Design: Cross-sectional study of 1,433 participants in the Chronic Renal Insufficiency Cohort (CRIC) Study (ie, the GFR subcohort) to derive an internal GFR estimating equation using a split-sample approach., Setting & Participants: Adults from 7 US metropolitan areas with mild to moderate chronic kidney disease; 48% had diabetes and 37% were black., Index Test: CRIC GFR estimating equation., Reference Test or Outcome: Urinary (125)I-iothalamate clearance testing (measured GFR [mGFR])., Other Measurements: Laboratory measures, including serum creatinine and cystatin C, and anthropometrics., Results: In the validation data set, the model that included serum creatinine level, serum cystatin C level, age, sex, and race was the most parsimonious and similarly predictive of mGFR compared with a model additionally including bioelectrical impedance analysis phase angle, CRIC clinical center, and 24-hour urinary creatinine excretion. Specifically, root mean square errors for the separate models were 0.207 versus 0.202, respectively. Performance of the CRIC GFR estimating equation was most accurate for the subgroups of younger participants, men, nonblacks, non-Hispanics, those without diabetes, those with body mass index <30 kg/m(2), those with higher 24-hour urine creatinine excretion, those with lower high-sensitivity C-reactive protein levels, and those with higher mGFRs., Limitations: Urinary clearance of (125)I-iothalamate is an imperfect measure of true GFR; cystatin C level is not standardized to certified reference material; lack of external validation; small sample sizes limit analyses of subgroup-specific predictors., Conclusions: The CRIC GFR estimating equation predicts mGFR accurately in the CRIC cohort using serum creatinine and cystatin C levels, age, sex, and race. Its performance was best in younger and healthier participants., (Copyright © 2012 National Kidney Foundation, Inc. All rights reserved.)

Patients with chronic kidney disease experience co-morbid illnesses, including cardiovascular disease (CVD) and retinopathy. The purpose of the present study was to assess the association between retinopathy and self-reported CVD in a subgroup of the participants in the Chronic Renal Insufficiency Cohort study. For this observational, ancillary investigation, 2,605 Chronic Renal Insufficiency Cohort participants were invited to participate in the present study, and nonmydriatic fundus photographs in both eyes were obtained for 1,936 subjects. The photographs were reviewed in a masked fashion at a central photograph reading center. The presence and severity of retinopathy (diabetic, hypertensive, or other) and vessel diameter caliber were assessed using standard protocols by trained graders who were masked to the information about the study participants. A history of self-reported CVD was obtained using a medical history questionnaire. Kidney function measurements and traditional and nontraditional risk factors for CVD were obtained from the Chronic Renal Insufficiency Cohort study. A greater severity of retinopathy was associated with a greater prevalence of any CVD, and this association persisted after adjustment for the traditional risk factors for CVD. The presence of vascular abnormalities usually associated with hypertension was also associated with increased prevalence of CVD. We found a direct relation between CVD prevalence and mean venular caliber. In conclusion, the presence of retinopathy was associated with CVD, suggesting that retinovascular pathology might indicate macrovascular disease, even after adjustment for renal dysfunction and traditional CVD risk factors. This would make the assessment of retinal morphology a valuable tool in CKD studies of CVD outcomes., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Depressive symptoms are correlated with poor health outcomes in adults with chronic kidney disease (CKD). The prevalence, severity, and treatment of depressive symptoms and potential risk factors, including level of kidney function, in diverse populations with CKD have not been well studied., Study Design: Cross-sectional analysis., Settings & Participants: Participants at enrollment into the Chronic Renal Insufficiency Cohort (CRIC) and Hispanic-CRIC (H-CRIC) Studies. CRIC enrolled Hispanics and non-Hispanics at 7 centers in 2003-2007, and H-CRIC enrolled Hispanics at the University of Illinois in 2005-2008., Measurement: Depressive symptoms measured by Beck Depression Inventory (BDI)., Predictors: Demographic and clinical factors., Outcomes: Elevated depressive symptoms (BDI score ≥11) and antidepressant medication use., Results: Of 3,853 participants, 27.4% had evidence of elevated depressive symptoms and 18.2% were using antidepressant medications; 31.0% of persons with elevated depressive symptoms were using antidepressants. The prevalence of elevated depressive symptoms varied by level of kidney function: 23.6% for participants with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m(2) and 33.8% of those with eGFR <30 mL/min/1.73 m(2). Lower eGFR (OR per 10-mL/min/1.73 m(2) decrease, 1.10; 95% CI, 1.04-1.17), and non-Hispanic black race (OR, 1.42; 95% CI, 1.16-1.74) were each associated with increased odds of elevated depressive symptoms after controlling for other factors. In regression analyses incorporating BDI score, whereas female sex was associated with greater odds of antidepressant use, Hispanic ethnicity, non-Hispanic black race, and higher urine albumin levels were associated with decreased odds of antidepressant use (P < 0.05 for each)., Limitations: Absence of clinical diagnosis of depression and use of nonpharmacologic treatments., Conclusions: Although elevated depressive symptoms were common in individuals with CKD, use of antidepressant medications is low. Individuals of racial and ethnic minority background and with more advanced CKD had a greater burden of elevated depressive symptoms and lower use of antidepressant medications., (Published by Elsevier Inc.)

This study was designed to examine the impact of elevated depressive affect on health outcomes among participants with hypertensive chronic kidney disease in the African-American Study of Kidney Disease and Hypertension (AASK) Cohort Study. Elevated depressive affect was defined by Beck Depression Inventory II (BDI-II) thresholds of 11 or more, above 14, and by 5-Unit increments in the score. Cox regression analyses were used to relate cardiovascular death/hospitalization, doubling of serum creatinine/end-stage renal disease, overall hospitalization, and all-cause death to depressive affect evaluated at baseline, the most recent annual visit (time-varying), or average from baseline to the most recent visit (cumulative). Among 628 participants at baseline, 42% had BDI-II scores of 11 or more and 26% had a score above 14. During a 5-year follow-up, the cumulative incidence of cardiovascular death/hospitalization was significantly greater for participants with baseline BDI-II scores of 11 or more compared with those with scores <11. The baseline, time-varying, and cumulative elevated depressive affect were each associated with a significant higher risk of cardiovascular death/hospitalization, especially with a time-varying BDI-II score over 14 (adjusted HR 1.63) but not with the other outcomes. Thus, elevated depressive affect is associated with unfavorable cardiovascular outcomes in African Americans with hypertensive chronic kidney disease.

Background and Objectives: Hispanics are the largest minority group in the United States. The leading cause of death in patients with chronic kidney disease (CKD) is cardiovascular disease (CVD), yet little is known about its prevalence among Hispanics with CKD., Design, Setting, Participants, & Measurements: We conducted cross-sectional analyses of prevalent self-reported clinical and subclinical measures of CVD among 497 Hispanics, 1638 non-Hispanic Caucasians, and 1650 non-Hispanic African Americans, aged 21 to 74 years, with mild-to-moderate CKD at enrollment in the Chronic Renal Insufficiency Cohort (CRIC) and Hispanic CRIC (HCRIC) studies. Measures of subclinical CVD included left ventricular hypertrophy (LVH), coronary artery calcification (CAC), and ankle-brachial index., Results: Self-reported coronary heart disease (CHD) was lower in Hispanics compared with non-Hispanic Caucasians (18% versus 23%, P = 0.02). Compared with non-Hispanic Caucasians, Hispanics had a lower prevalence of CAC >100 (41% versus 34%, P = 0.03) and CAC >400 (26% versus 19%, P = 0.02). However, after adjusting for sociodemographic factors, these differences were no longer significant. In adjusted analyses, Hispanics had a higher odds of LVH compared with non-Hispanic Caucasians (odds ratio 1.97, 95% confidence interval, 1.22 to 3.17, P = 0.005), and a higher odds of CAC >400 compared with non-Hispanic African Americans (odds ratio, 2.49, 95% confidence interval, 1.11 to 5.58, P = 0.03). Hispanic ethnicity was not independently associated with any other CVD measures., Conclusions: Prevalent LVH was more common among Hispanics than non-Hispanic Caucasians, and elevated CAC score was more common among Hispanics than non-Hispanic African Americans. Understanding reasons for these racial/ethnic differences and their association with long-term clinical outcomes is needed.

Background: Little is known regarding chronic kidney disease (CKD) in Hispanics. We compared baseline characteristics of Hispanic participants in the Chronic Renal Insufficiency Cohort (CRIC) and Hispanic-CRIC (H-CRIC) Studies with non-Hispanic CRIC participants., Study Design: Cross-sectional analysis., Setting & Participants: Participants were aged 21-74 years with CKD using age-based estimated glomerular filtration rate (eGFR) at enrollment into the CRIC/H-CRIC Studies. H-CRIC included Hispanics recruited at the University of Illinois in 2005-2008, whereas CRIC included Hispanics and non-Hispanics recruited at 7 clinical centers in 2003-2007., Factor: Race/ethnicity., Outcomes: Blood pressure, angiotensin-converting enzyme (ACE)-inhibitor/angiotensin receptor blocker (ARB) use, and CKD-associated complications., Measurements: Demographic characteristics, laboratory data, blood pressure, and medications were assessed using standard techniques and protocols., Results: Of H-CRIC/CRIC participants, 497 were Hispanic, 1,650 were non-Hispanic black, and 1,638 were non-Hispanic white. Low income and educational attainment were nearly twice as prevalent in Hispanics compared with non-Hispanics (P < 0.01). Hispanics had self-reported diabetes (67%) more frequently than non-Hispanic blacks (51%) and whites (40%; P < 0.01). Blood pressure >130/80 mm Hg was more common in Hispanics (62%) than blacks (57%) and whites (35%; P < 0.05), and abnormalities in hematologic, metabolic, and bone metabolism parameters were more prevalent in Hispanics (P < 0.05), even after stratifying by entry eGFR. Hispanics had the lowest use of ACE inhibitors/ARBs among the high-risk subgroups, including participants with diabetes, proteinuria, and blood pressure >130/80 mm Hg. Mean eGFR was lower in Hispanics (39.6 mL/min/1.73 m(2)) than in blacks (43.7 mL/min/1.73 m(2)) and whites (46.2 mL/min/1.73 m(2)), whereas median proteinuria was higher in Hispanics (protein excretion, 0.72 g/d) than in blacks (0.24 g/d) and whites (0.12 g/d; P < 0.01)., Limitations: Generalizability; observed associations limited by residual bias and confounding., Conclusions: Hispanics with CKD in the CRIC/H-CRIC Studies are disproportionately burdened with lower socioeconomic status, more frequent diabetes mellitus, less ACE-inhibitor/ARB use, worse blood pressure control, and more severe CKD and associated complications than their non-Hispanic counterparts., (Published by Elsevier Inc.)

Hispanics are the fastest growing minority group in the United States, and compared with non-Hispanic whites, they have a higher incidence of end-stage renal disease. Examining novel factors that may explain this disparity in progression of chronic kidney disease (CKD) in Hispanics is urgently needed. Interpersonal and patient-centered characteristics, including health literacy, acculturation, and social support, have been shown to affect health outcomes in patients with other chronic diseases. However, these characteristics have not been well studied in the context of CKD, particularly in relation to disease knowledge, attitudes, and behaviors. In this report, we examine the potential roles of these factors for CKD progression in Hispanics and propose targeted therapeutic interventions., (Copyright © 2011 National Kidney Foundation, Inc. All rights reserved.)

Fibroblast growth factor 23 (FGF23) regulates phosphorus metabolism and is a strong predictor of mortality in dialysis patients. FGF23 is thought to be an early biomarker of disordered phosphorus metabolism in the initial stages of chronic kidney disease (CKD). We measured FGF23 in baseline samples from 3879 patients in the Chronic Renal Insufficiency Cohort study, which is a diverse cohort of patients with CKD stage 2-4. Mean serum phosphate and median parathyroid hormone (PTH) levels were in the normal range, but median FGF23 was markedly greater than in healthy populations, and increased significantly with decreasing estimated glomerular filtration rate (eGFR). High levels of FGF23, defined as being above 100 RU/ml, were more common than secondary hyperparathyroidism and hyperphosphatemia in all strata of eGFR. The threshold of eGFR at which the slope of FGF23 increased was significantly higher than the corresponding threshold for PTH based on non-overlapping 95% confidence intervals. Thus, increased FGF23 is a common manifestation of CKD that develops earlier than increased phosphate or PTH. Hence, FGF23 measurements may be a sensitive early biomarker of disordered phosphorus metabolism in patients with CKD and normal serum phosphate levels.

Background: Epidemiological studies typically diagnose heart failure (HF) at the time of hospitalization, and have not evaluated the prevalence of HF symptoms in CKD patients without a prior HF diagnosis., Methods and Results: We modified the Kansas City Cardiomyopathy Questionnaire (KCCQ) to detect and quantify symptoms characteristic of HF (dyspnea, edema, and fatigue) among 2883 chronic kidney disease (CKD) patients without diagnosed heart failure in the Chronic Renal Insufficiency Cohort (CRIC). The KCCQ is a 23-item instrument that quantifies the impact of dyspnea, fatigue, and edema on physical, social, and emotional functions (scored 0 to 100). The median KCCQ score was 92, and 25% had KCCQ scores <75. Compared with cystatin C‑based estimated glomerular filtration rate >50 mL·min·1.73 m(2) (reference), estimated glomerular filtration rate 40 to 50, 30 to 40, and <30 were independently associated with lower KCCQ scores (<75); adjusted odds ratios and (95% CI): 1.38 (1.06-1.78), 1.39 (1.09-1.82), and 2.15 (1.54-3.00), respectively. Lower hemoglobin (Hb) levels also had independent associations with KCCQ <75: Hb >14 g/dL (reference), Hb 13 to 14 g/dL (1.03; 0.76-1.40), Hb 12 to 13 g/dL (1.41; 1.04-1.91), Hb 11 to 12 g/dL (1.56; 1.12-2.16); and Hb <1 g/dL (1.65; 1.15-2.37)., Conclusion: CKD patients without diagnosed HF have a substantial burden of symptoms characteristic of HF, particularly among those with lower estimated glomerular filtration rate and hemoglobin levels., (Published by Elsevier Inc.)

Background and Objective: Depression is common in individuals with end-stage renal disease. However, its relationship with earlier stages of chronic kidney disease (CKD) is less well known. In this study, we examined the association between depressive symptoms and CKD., Methods: Cross-sectional analysis of the prevalence and correlates of depressive symptoms were measured by the Patient Health Questionnaire (PHQ-9) among adult participants with CKD in the National Health and Nutrition Examination Survey 2005-2006. CKD was defined according to estimated glomerular filtration rate by Modification of Diet in Renal Disease Study equation of <60 ml/min/1.73 m(2) or the presence of microalbuminuria (≥ 30 mg/g creatinine), using the Kidney Disease Outcomes Quality Initiative classification. A PHQ-9 score ≥ 10 was considered to be indicative of depressive symptoms., Results: Among 3653 subjects in our study sample, 683 (15.2%) met laboratory criteria for CKD. The prevalence of depressive symptoms was 7% (95% confidence interval [CI] 3.2-10.8%) in subjects with CKD and 6% (95% CI 4.6-7.4%) in subjects without CKD (P = 0.6). In regression analysis, the presence of CKD was not significantly associated with depressive symptoms (adjusted odds ratio = 0.96 [95% CI 0.51, 1.78], P = 0.9)., Conclusions: We found no difference in the prevalence of depressive symptoms among individuals with or without CKD.

Background: In observational studies, the relationship between blood pressure and end-stage renal disease (ESRD) is direct and progressive. The burden of hypertension-related chronic kidney disease and ESRD is especially high among black patients. Yet few trials have tested whether intensive blood-pressure control retards the progression of chronic kidney disease among black patients., Methods: We randomly assigned 1094 black patients with hypertensive chronic kidney disease to receive either intensive or standard blood-pressure control. After completing the trial phase, patients were invited to enroll in a cohort phase in which the blood-pressure target was less than 130/80 mm Hg. The primary clinical outcome in the cohort phase was the progression of chronic kidney disease, which was defined as a doubling of the serum creatinine level, a diagnosis of ESRD, or death. Follow-up ranged from 8.8 to 12.2 years., Results: During the trial phase, the mean blood pressure was 130/78 mm Hg in the intensive-control group and 141/86 mm Hg in the standard-control group. During the cohort phase, corresponding mean blood pressures were 131/78 mm Hg and 134/78 mm Hg. In both phases, there was no significant between-group difference in the risk of the primary outcome (hazard ratio in the intensive-control group, 0.91; P=0.27). However, the effects differed according to the baseline level of proteinuria (P=0.02 for interaction), with a potential benefit in patients with a protein-to-creatinine ratio of more than 0.22 (hazard ratio, 0.73; P=0.01)., Conclusions: In overall analyses, intensive blood-pressure control had no effect on kidney disease progression. However, there may be differential effects of intensive blood-pressure control in patients with and those without baseline proteinuria. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases, the National Center on Minority Health and Health Disparities, and others.)