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Postacute myocardial infarction (AMI) readmissions are common among Medicare beneficiaries (≥65 years) and are associated with significant resource utilization. However, patterns of AMI readmissions for younger age groups in the United States are not known. In the Nationwide Readmissions Database, a nationally representative all-payer database of in-patient hospitalizations, we identified 212,171 index AMI hospitalizations in January to November 2013, weighted to represent 478,247 hospitalizations nationally (mean age 66.9 years, 38% women, 29% low income). This included 26,516 cases in the 18 to 44 age group, 183,703 in the 45 to 64 age group, and 268,027 in the ≥65 age group. The overall 30-day readmission rate was 14.5% and varied across age groups (9.7% [18 to 44], 11.2% [45 to 64], and 17.3% [≥65]). The cumulative cost of 30-day readmissions was $1.1 billion, of which $365 million was spent on those

Previous studies have demonstrated ethnic/racial differences in cardiorespiratory fitness (CRF). However, the relative contributions of body mass index (BMI), lifestyle behaviors, socioeconomic status (SES), cardiovascular (CV) risk factors, and cardiac function to these differences in CRF are unclear. In this study, we included 2,617 Dallas Heart Study participants (58.6% women, 48.6% black; 15.7% Hispanic) without CV disease who underwent estimation of CRF using a submaximal exercise test. We constructed multivariable-adjusted linear regression models to determine the association between race/ethnicity and CRF, which was defined as peak oxygen uptake (ml/kg/min). Black participants had the lowest CRF (blacks: 26.3 ± 10.2; whites: 29.0 ± 9.8; Hispanics: 29.1 ± 10.0 ml/kg/min). In multivariate analysis, both black and Hispanic participants had lower CRF after adjustment for age and gender (blacks: Std β = -0.15; p value ≤0.0001, Hispanics: Std β = -0.05, p value = 0.01; ref group: whites). However, this association was considerably attenuated for black (Std β = -0.04, p value = 0.03) and no longer significant for Hispanic ethnicity (p value = 0.56) after additional adjustment for BMI, lifestyle factors, SES, and CV risk factors. Additional adjustment for stroke volume did not substantially change the association between black race/ethnicity and CRF (Std β = -0.06, p value = 0.01). In conclusion, BMI, lifestyle, SES, and traditional risk factor burden are important determinants of ethnicity-based differences in CRF.

Premature clopidogrel discontinuation is an important cause of stent thrombosis, myocardial infarction, and death after drug-eluting stent (DES) placement. Previous studies of clopidogrel nonadherence after DES placement have had short follow-up and have relied on self-reported adherence. All patients who underwent DES placement from January 2008 to December 2011 at a single safety-net hospital and received medications through the county-subsidized health plan were considered for inclusion; those with1-year follow-up were excluded. We retrospectively collected 1-year refill data from a large, closed pharmacy system. Our primary outcome was time to failure to obtain a clopidogrel refill, allowing a 5-day grace period. Our study cohort (n = 369) was 34% female, 39% Hispanic, 26% white, and 26% African-American; 26% identified Spanish as their primary language. The time to failure to obtain a clopidogrel refill was 153 days. Cumulative failure to obtain at least 1 refill was 23% for the first refill, increasing to 52% at 6 months and 68% at 1 year. Examining the proportion of days covered (PDC), 21% of patients had 100% coverage, whereas 34% had PDC80%. There were no independent predictors of nonadherence (PDC80%). In conclusion, we identified a high rate of clopidogrel nonadherence in a multiethnic urban poor patient population where clopidogrel was provided at discharge and at nominal cost thereafter. In this cohort, prediction models of nonadherence performed poorly. Novel strategies are needed to address this important problem.

Therapies targeting high-density lipoprotein cholesterol content (HDL-C) have not improved coronary heart disease (CHD) outcomes. High-density lipoprotein particle concentration (HDL-P) may better predict CHD. However, the impact of race/ethnicity on the relations between HDL-P and subclinical atherosclerosis and incident CHD events has not been described. Participants from the Dallas Heart Study (DHS), a multiethnic, probability-based, population cohort of Dallas County adults, underwent the following baseline measurements: HDL-C, HDL-P by nuclear magnetic resonance imaging, and coronary artery calcium by electron-beam computed tomography. Participants were followed for a median of 9.3 years for incident CHD events (composite of first myocardial infarction, stroke, coronary revascularization, or cardiovascular death). The study comprised 1,977 participants free of CHD (51% women, 46% black). In adjusted models, HDL-C was not associated with prevalent coronary artery calcium (p = 0.13) or incident CHD overall (hazard ratio [HR] per 1 SD 0.89, 95% confidence interval [CI] 0.76 to 1.05). However, HDL-C was inversely associated with incident CHD among nonblack (adjusted HR per 1 SD 0.67, 95% CI 0.46 to 0.97) but not black participants (HR 0.94, 95% CI 0.78 to 1.13, p interaction = 0.05). Conversely, HDL-P, adjusted for risk factors and HDL-C, was inversely associated with prevalent coronary artery calcium (p = 0.009) and with incident CHD overall (adjusted HR per 1 SD 0.73, 95% CI 0.62 to 0.86), with no interaction by black race/ethnicity (p interaction = 0.57). In conclusion, in contrast to HDL-C, the inverse relation between HDL-P and incident CHD events is consistent across ethnicities. These findings suggest that HDL-P is superior to HDL-C in predicting prevalent atherosclerosis as well as incident CHD events across a diverse population and should be considered as a therapeutic target.

Large randomized trials have provided inconsistent evidence regarding the benefit of intensive blood pressure (BP) lowering in hypertensive patients. Identifying which patients derive a higher net benefit is essential in informing clinical decision-making. We used patient-level data from 2 trials that tested intensive versus standard BP lowering, Systolic Blood Pressure Intervention Trial (SPRINT) and Action to Control Cardiovascular Risk in Diabetes (ACCORD), to assess whether stratification by cardiovascular disease (CVD) risk will identify patients with a more favorable risk-benefit profile for intensive BP lowering. Within SPRINT, we selected a subset of patients at the extremes of major adverse cardiovascular event rates to develop a decision tree using recursive partitioning modeling. We then validated its predictive effects in the remaining ‘intermediate’ SPRINT subset (n = 8,357) and externally in ACCORD (n = 2,258). Recursive partitioning produced a 3-variable decision tree model consisting of age ≥74 years, urinary albumin-creatinine ratio ≥34, and history of clinical CVD. It classified 48.6% of SPRINT and 55.3% of ACCORD patients as “high-risk.” Compared with standard treatment, intensive BP lowering was associated with lower rates of major adverse cardiovascular event in this high-risk population in both SPRINT cross-validation data (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.52 to 0.85) and ACCORD (HR 0.67, 95% CI 0.50 to 0.90), but not in the remaining low-risk patients (SPRINT: HR 0.83, 95% CI 0.56 to 1.25; ACCORD: HR 1.09, 95% CI 0.64 to 1.83). Additionally, intensive BP lowering did not confer an excess risk of serious adverse events in the high-risk group. In conclusion, this simple risk prediction model consisting of age, urinary albumin-creatinine ratio, and clinical CVD history successfully identified a subset of hypertensive patients who derived a more favorable risk-benefit profile for intensive BP lowering.

The relations between renal function and circulating B-type natriuretic peptide (BNP) and the amino-terminal fragment of its prohormone (NT-pro-BNP) in the general population have not been fully elucidated. A total of 2,784 subjects from the Dallas Heart Study, a multiethnic population-based sample of Dallas County, Texas, residents, was studied. Detailed cardiac phenotyping, including magnetic resonance imaging and electron beam computed tomography, as well as measurements of NT-pro-BNP and BNP, were performed. Associations between estimated glomerular filtration rate (eGFR) and both NT-pro-BNP and BNP were evaluated using multivariable statistical analysis techniques. Median eGFR in this young, predominantly healthy population was 97 ml/min/1.73 m(2) (interquartile range 84 to 112). Natriuretic peptide levels were not associated with renal function over the normal range of eGFR. Below a threshold eGFR of 90 ml/min/1.73 m(2), both NT-pro-BNP and BNP increased in an exponential fashion with decreasing eGFR. These associations remained significant after adjustment for multiple potential confounders (p

Elevated plasma levels of B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-pro-BNP) are seen in the setting of cardiac ischemia and are associated with adverse outcomes in patients with coronary artery disease. The mechanisms leading to natriuretic peptide elevation in patients with coronary artery disease, including the contribution of coronary atherosclerosis itself, have not been fully elucidated. Measurement of NT-pro-BNP, electron beam computed tomography, and cardiac magnetic resonance imaging were performed in 2,445 subjects from the Dallas Heart Study who were free of heart failure and renal insufficiency. Electron beam computed tomography-determined coronary artery calcium scores were categorized as none (10), mild (or =10 to100), moderate (or =100 to400), and severe (or =400). NT-pro-BNP levels increased significantly across increasing coronary artery calcium score categories (p0.0001 for trend). In multivariate models adjusted for age, gender, race, body mass index, hypertension, history of myocardial infarction, angina, angiotensin-converting enzyme inhibitor use, beta-blocker use, left ventricular (LV) ejection fraction, and LV mass, higher coronary artery calcium scores remained independently associated with higher log NT-pro-BNP levels (p = 0.03). This association persisted in similar models excluding patients with low LV ejection fractions, LV hypertrophy, angina pectoris, and a history of myocardial infarction. In conclusion, these findings support the hypothesis that coronary atherosclerosis may directly influence the activation of the cardiac neurohormonal system.

The relation between hematocrit and progression from asymptomatic left ventricular (LV) systolic dysfunction to symptomatic heart failure (HF) was examined in 2,821 patients from the Studies of Left Ventricular Dysfunction Prevention trial. Patients in the lowest hematocrit quartile (hematocritor = 40%) were at increased risk for the development of HF symptoms (hazard ratio [HR] 1.79, 95% confidence interval [CI] 1.37 to 2.34), first HF hospitalization (HR 2.35, 95% CI 1.52 to 3.62), and death or the development of HF symptoms (HR 1.60, 95% CI 1.28 to 1.99) compared with patients in the highest hematocrit quartile (hematocrit46%).