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Early morning blood pressure surge (MBPS) is a risk factor for cardiovascular events (CVEs), but the relationship with uric acid is not well understood. The authors aimed to determine the association between MBPS and increased uric acid and the effect of elevated MBPS and uric acid combination on CVEs. A total of 921 patients underwent 24-hour ambulatory blood pressure monitoring and were followed for a median of 40 months. During this period, 103 (11.2%) CVEs occurred. There was a significant relationship between increasing quartiles of serum uric acid level and increasing values of MBPS (P<.0001). Patients in the highest quartile stratified by elevated MBPS and serum uric acid level had a 3.55 odds of major CVE compared with patients in the lowest quartile. Serum uric acid is associated with MBPS and development of new CVEs., (©2014 Wiley Periodicals, Inc.)

The relationship between dietary sodium and potassium intake with elevated blood pressure (BP) levels is unclear. The authors examined the association between dietary sodium and potassium intake and BP levels in 6985 adults aged 18 years and older with no prior history of hypertension who participated in the National Health and Nutrition Examination Survey (2001-2006). After adjustment for age, sex, race, body mass index, diabetes, and estimated glomerular filtration rate, there was no association between higher quartiles of sodium or potassium intake with the risk of a BP >140/90 mm Hg or >130/80 mm Hg. There was also no relationship between dietary sodium and potassium intake with BP when systolic and diastolic BP were measured as continuous outcomes (P=.68 and P=.74, respectively). Furthermore, no association was found between combinations of sodium and potassium intake with elevated BP. In the US adult population without hypertension, increased dietary sodium or low potassium intake was not associated with elevated BP levels., (©2014 Wiley Periodicals, Inc.)

Uric acid (UA) is independently associated with the emergence of hypertension. Nocturnal nondipping pattern of hypertension is associated with a greater risk of cardiovascular, renal, and cerebrovascular complications than dippers. The aim of the present study was to evaluate the relationship between the circadian blood pressure rhythm and UA level in patients with newly diagnosed essential hypertension. The study included 112 essential hypertensive patients and 50 healthy controls. The hypertensive patients were divided into two groups according to the results of 24-hour ambulatory blood pressure monitoring, including 60 dippers (35 men, 25 women; mean age, 52.6±15.8 years) and 52 nondippers (29 men, 23 women; mean age, 55.9±13.2 years). Nondippers had significantly higher serum UA levels than the dippers and controls (5.8±0.8, 5.1±0.9 and 4.2±0.9 mg/dL, respectively; P<.001). Serum high-sensitivity C-reactive protein levels were also significantly higher in the nondipper group than the other groups (P<.001) and significantly correlated with serum UA (r=0.358, P<.001). Multivariate logistic regression analysis revealed an independent positive association between serum UA levels and nondipper pattern (odds ratio, 2.28; 95% confidence interval, 1.33-3.94; P=.003). Serum UA is strongly and independently associated with the nondipper circadian pattern in essential hypertension., (© 2012 Wiley Periodicals, Inc.)

Background and Objectives: Autosomal dominant polycystic kidney disease (ADPKD) is a progressive hereditary disorder affecting children and young adults. Early intervention may be necessary to significantly affect the long-term consequences of this disease., Design, Setting, Participants, & Measurements: The authors conducted a 5-yr randomized clinical trial to assess the effect of BP control with angiotensin-converting enzyme inhibition (ACEI) on disease progression in 85 children and young adults with ADPKD. Study groups were determined by subject BP, including hypertension (BP >or= 95th percentile), borderline hypertension (BP 75 to 95th percentile), and severe ADPKD (BP 10 renal cysts). The primary outcome variable was renal volume by ultrasound, with secondary outcome variables including left ventricular mass index (LVMI) and microalbuminuria. In secondary analysis, the authors compared results between hypertensive and normotensive groups., Results: The authors were not able to demonstrate a significant effect of ACEI on renal growth in young subjects with ADPKD. Hypertensive children were at particular risk for increases in renal volume and LVMI and decreased renal function as compared with the other study groups, and borderline hypertensive children were at high risk to develop hypertension over time. However, ACEI treatment was associated with stable renal function and LVMI in this group of children., Conclusions: Close monitoring of cardiovascular and renal status is indicated in ADPKD children with hypertension or borderline hypertension. In contrast to effects in hypertensive ADPKD children, ACEI treatment in normotensive or borderline hypertensive ADPKD children may prevent the development of increased LVMI and deterioration in renal function.

Autosomal dominant polycystic kidney disease (ADPKD) is a common hereditary condition that may be diagnosed in utero. Our goal was to evaluate symptoms of ADPKD in children, including left ventricular mass index (LVMI), renal volume, renal function and microalbuminuria in relation to systolic and diastolic blood pressure. Eighty-five children were stratified by blood pressure into three cohorts: hypertensive (95th percentile and over), borderline hypertensive (75-95th percentile) and normotensive (75th percentile and below). There were no differences in gender, age, height, renal function, or microalbuminuria between the groups. Both the hypertensive and borderline hypertensive children had a significantly higher LVMI than normotensive children, with no significant difference between hypertensive and borderline hypertensive groups. There was a significant correlation between renal volume and both systolic and diastolic blood pressures in all subjects. Renal volume in hypertensive children was significantly larger than in the borderline hypertensive group, with no significant difference between normotensive and borderline hypertensive groups. These findings show that an increase in LVMI may be detected earlier than an increase in renal volume in children with ADPKD and borderline hypertension, suggesting that close monitoring of cardiac status is indicated in these children.

Background: Patients with autosomal dominant polycystic kidney disease (ADPKD) often develop hypertension before any abnormalities in renal function are detected clinically. Therefore, standard screening (serum creatinine and urinalysis) of young individuals with unexplained hypertension to exclude renal parenchymal disease would rarely detect ADPKD., Methods: Data from 516 subjects with ADPKD (217 male and 299 female), aged newbornto 55 years with a normal serum creatinine and no proteinuria based on urine dipstick, studied between 1985 and 2000, were compared with data from similar subjects from the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and NHANES IV (1999-2000) data, by gender., Results: There was a highly significant occurrence of hypertension in young patients with ADPKD when compared to patients aged 20 to 34 years in the U.S. population. The hypertension in patients with ADPKD occurred in the absence of abnormal renal function or abnormal urinalysis., Conclusions: These data indicate that renal ultrasound screening of young hypertensive individuals (aged 20 to 34 years) should be considered when searching for causes of secondary hypertension. Identifying affected ADPKD individuals early in their disease will permit aggressive blood pressure treatment and early inhibition of the renin-angiotensin-aldosterone system, which has been shown to reverse left ventricular hypertrophy, an important cardiovascular risk factor. In the present era of renal replacement therapy, cardiovascular complications are the main cause of death in patients with ADPKD.

ObjectivesIn chronic kidney disease (CKD), high FGF23 concentrations are associated with left ventricular hypertrophy (LVH), cardiovascular events, and death. The associations of FGF23 with left ventricular mass (LVM) and LVH in the general population and the influence of CKD remains uncertain.MethodsC-terminal plasma FGF23 concentrations were measured, and LVM and LVH evaluated by echocardiogram among 2255 individuals ≥65 years in the Cardiovascular Health Study. Linear regression analysis adjusting for demographics, cardiovascular, and kidney related risk factors examined the associations of FGF23 concentrations with LVM. Analyses were stratified by CKD status and adjusted linear and logistic regression analysis explored the associations of FGF23 with LVM and LVH.ResultsAmong the entire cohort, higher FGF23 concentrations were associated with greater LVM in adjusted analyses (β = 6.71 [95% CI 4.35-9.01] g per doubling of FGF23). 32% (n = 624) had CKD (eGFR 30 mg/g). Associations were stronger among participants with CKD (p interaction = 0.006): LVM β = 9.71 [95% CI 5.86-13.56] g per doubling of FGF23 compared to those without CKD (β = 3.44 [95% CI 0.77, 6.11] g per doubling of FGF23). While there was no significant interaction between FGF23 and CKD for LVH (p interaction = 0.25), the OR (1.46 95% CI [1.20-1.77]) in the CKD group was statistically significant and of larger magnitude than the OR for in the no CKD group (1.12 [95% CI 0.97-1.48]).ConclusionIn a large cohort of older community-dwelling adults, higher FGF23 concentrations were associated with greater LVM and LVH with stronger relationships in participants with CKD.

BACKGROUND Uric acid is associated with increased risk of cardiovascular disease and arterial stiffness in patients with hypertension or stroke. It remains unknown if uric acid is associated with arterial stiffness in the general population. METHODS We analyzed the association between serum uric acid levels and measures of arterial stiffness such as carotid-femoral pulse wave velocity (CF PWV), carotid-radial pulse wave velocity (CR PWV) and augmentation index (AI) in 4,140 participants from the Generation 3 Framingham cohort using linear regression. RESULTS Mean (SD) age was 40.0 (8.8) years and mean (SD) serum uric acid levels were 5.3 (1.5) mg/dl. Mean (SD) CF PWV was 7.0 (1.4) m/s. Individuals in the highest quartile of uric acid were more likely to be male, have a higher prevalence of hypertension, higher BMI, fasting glucose and insulin, and lower estimated glomerular filtration rate (eGFR). Multivariate adjusted means of CF PWV were 6.90, 6.94, 7.06, and 7.15 m/s for uric acid quartile 1, 2, 3, and 4 respectively. In unadjusted analysis each 1 mg/dl increase in uric acid was associated with higher CF-PWV (β = 0.27; 95% CI = 0.25, 0.29; P < 0.0001). This was attenuated but remained significant after adjusting for age, sex, smoking, hypertension, BMI, fasting glucose, insulin, animal protein intake, and eGFR (β= 0.06; 95% CI = 0.02, 0.09; P < 0.0007). There was no association between serum uric acid levels and AI upon adjustment for cardiovascular risk factors. CONCLUSIONS Serum uric acid levels are significantly associated with CF PWV and CR PWV in a younger Caucasian population. [ABSTRACT FROM AUTHOR]

Background Hyperuricemia has been implicated in the development and progression of chronic kidney disease, both in animal experiments and in clinical studies. As a potentially modifiable risk factor, we examined whether serum uric acid levels correlate with early hypertension, kidney volume and progression to end-stage renal disease (ESRD) in autosomal-dominant polycystic kidney disease (ADPKD). Methods Retrospective analysis of a prospective observational study of the natural history of ADPKD, conducted at the University of Colorado between 1985 and 2005. Included are 680 ADPKD adults who provided data on blood pressure, renal volume, renal function, uric acid, age at the onset of ESRD or last known age without ESRD. Serum uric acid levels were examined as a continuous variable and as gender-specific quartiles. The main outcome of interest was age at the onset of ESRD; secondary outcomes were hypertension onset before age 30 years and total kidney volume (TKV) at the study visit. Results Subjects with early-onset hypertension had higher age-adjusted serum uric acid levels than those with no or late-onset hypertension despite similar creatinine clearance. After adjusting for age, gender and creatinine clearance, there was a 5.8% increase in TKV and 4.1% increase in TKV/body surface area for every 1 mg/dL increase in uric acid (P = 0.007). The multivariate-adjusted Cox regression demonstrated a greater hazard ratio for ESRD for subjects in the 4th and 3rd quartiles of uric acid compared with the 1st [4.8 (2.6–8.9; P < 0.001) and 2.9 (1.6–5.3; P < 0.001)]. Conclusions Higher serum uric acid levels are associated with earlier onset of hypertension, larger kidney volume and increased hazard for ESRD in ADPKD independent of gender, body mass index and renal function at the study visit. Randomized interventional studies will be necessary to examine whether treating hyperuricemia has a protective role in ADPKD. [ABSTRACT FROM AUTHOR]

Background The epidemic of obesity and diabetes is increasing within the USA and worldwide. We have previously shown that body mass index has increased significantly in autosomal dominant polycystic kidney disease (ADPKD) subjects seen at our center in more recent years. However, the impact of Type II diabetes in ADPKD patients has not been well studied. Methods This retrospective cohort study compared clinical characteristics in 44 pre-renal transplant patients with ADPKD and diabetes and 88 age- and sex-matched non-diabetic patients with ADPKD who were seen at the University of Colorado between 1977 and 2008. The primary outcomes in this study were renal volume determined by renal ultrasonography, renal function assessed by estimated glomerular filtration rate and time to onset of end-stage renal disease or death by Kaplan–Meier analyses. Results Diabetic patients had significantly larger kidney volumes than those with ADPKD alone [geometric mean (95% confidence interval (CI)]: 2456 (1510–3992) versus 1358 (1186–1556) cm3, P = 0.02. Among those whose age at hypertension diagnosis was known, the diabetic ADPKD patients had earlier median (95% CI) age at onset of hypertension compared to those with ADPKD alone: 32.5 (28–40) versus 38 (35–42) years, P = 0.04. Diabetic ADPKD patients tended to have an earlier median age of death than those with ADPKD alone. Conclusions Patients with ADPKD and type II diabetes have larger renal volumes, earlier age at diagnosis of hypertension and may die at a younger age compared to those patients with ADPKD alone. This study emphasizes the importance of diabetes risk management in ADPKD. [ABSTRACT FROM PUBLISHER]

The role of parental hypertension in the frequency and age of diagnosis of hypertension in offspring with autosomal-dominant polycystic kidney disease. Hypertension in autosomal-dominant polycystic kidney disease (ADPKD) patients is associated with more rapid progression of renal disease and a high incidence of left ventricular hypertrophy (LVH). The present study was undertaken to examine the role of parental hypertension in the occurrence of hypertension in 475 ADPKD offspring. Adult subjects participating in an ongoing study of the natural history of ADPKD were included in the analysis if they were diagnosed with ADPKD, had a known affected parent, and knew the hypertensive status of both parents. When the affected parent was hypertensive, the ADPKD male (82% versus 62%, P < 0.05) and female (61% versus 37%, P < 0.005) offspring had a significantly higher frequency of hypertension than when the ADPKD-affected parent was normotensive. The median age of diagnosis of hypertension was also significantly earlier in both male (33 years versus 40 years, P < 0.05) and female (38 years versus 50 years, P < 0.05) ADPKD patients when their affected parents were hypertensive as compared with normotensive. These effects of hypertension in the affected parent on hypertension in the ADPKD offspring were independent of age, renal volume, and renal function in the offspring. Hypertension in unaffected parents also increased the frequency of hypertension in the ADPKD female (69% versus 53%, P < 0.01), but not male (89% versus 77%, NS) subjects. The results indicate that parental hypertension influences the frequency of hypertension in ADPKD patients. [ABSTRACT FROM AUTHOR]