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Study Objectives: To examine the cross-sectional association between obstructive sleep apnea (OSA) risk and atrial fibrillation (AF) in the REasons for Geographic And Racial Differences in Stroke (REGARDS), a cohort of black and white adults., Methods: Using REGARDS data from subjects recruited between 2003-2007, we assessed 20,351 participants for OSA status. High OSA risk was determined if the participant met at least two criteria from the Berlin Sleep Questionnaire (persistent snoring, frequent sleepiness, high blood pressure, or obesity). AF was defined as a self-reported history of a previous physician diagnosis or presence of AF on electrocardiogram. Logistic regression was used to determine odds ratio and 95% confidence interval for the association between OSA status and AF with subgroup analysis to examine effect modification by age, race, sex, and geographical region., Results: The prevalence of AF was 7% (n = 1,079/14,992) and 9% (n = 482/5,359) in participants at low and high risk of OSA, respectively ( P < .0001). Persons at high risk of OSA had greater prevalence of diabetes and stroke history, and were more likely to be obese and taking sleep medications. In a multivariable analysis adjusted for demographics, cardiovascular risk factors, and potential confounders, high risk for OSA was associated with an increased odds of AF compared to low risk for OSA (odds ratio = 1.27, 95% confidence interval = 1.13, 1.44). This association differed significantly only by race ( P for interaction = .0003). For blacks, there was a significant 58% increase in odds of AF in participants at high risk versus low risk of OSA, compared to a nonsignificant 12% increase in odds in whites. We were limited by self-reported variables, inability to adjust for obesity, and the cross-sectional nature of our study., Conclusions: High risk of OSA is associated with prevalent AF among blacks but not whites., Commentary: A commentary on this article appears in this issue on page 1459., (© 2018 American Academy of Sleep Medicine.)

Background: N-terminal pro B-type peptide (NT-proBNP) has been associated with risk of myocardial infarction (MI), but less is known about the relationship between NT-proBNP and very small non ST-elevation MI, also known as microsize MI. These events are now routinely detectable with modern troponin assays and are emerging as a large proportion of all MI. Here, we sought to compare the association of NT-proBNP with risk of incident typical MI and microsize MI in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study., Methods: The REGARDS Study is a national cohort of 30,239 US community-dwelling black and white adults aged ≥ 45 years recruited from 2003 to 2007. Expert-adjudicated outcomes included incident typical MI (definite/probable MI with peak troponin ≥ 0.5 μg/L), incident microsize MI (definite/probable MI with peak troponin < 0.5 μg/L), and incident fatal CHD. Using a case-cohort design, we estimated the hazard ratio of the outcomes as a function of baseline NT-proBNP. Competing risk analyses tested whether the associations of NT-proBNP differed between the risk of incident microsize MI and incident typical MI as well as if the association of NT-proBNP differed between incident non-fatal microsize MI and incident non-fatal typical MI, while accounting for incident fatal coronary heart disease (CHD) as well as heart failure (HF)., Results: Over a median of 5 years of follow-up, there were 315 typical MI, 139 microsize MI, and 195 incident fatal CHD. NT-proBNP was independently and strongly associated with all CHD endpoints, with significantly greater risk observed for incident microsize MI, even after removing individuals with suspected HF prior to or coincident with their incident CHD event., Conclusion: NT-proBNP is associated with all MIs, but is a more powerful risk factor for microsize than typical MI.

Background: The National Death Index (NDI) is widely used to detect coronary heart disease (CHD) and cardiovascular disease (CVD) deaths, but its reliability has not been examined recently., Methods and Results: We compared CHD and CVD deaths detected by NDI with expert adjudication of 4010 deaths that occurred between 2003 and 2013 among participants in the REGARDS (REasons for Geographic And Racial Differences in Stroke) cohort of black and white adults in the United States. NDI derived CHD mortality had sensitivity 53.6%, specificity 90.3%, positive predictive value 54.2%, and negative predictive value 90.1%. NDI-derived CVD mortality had sensitivity 73.4%, specificity 84.5%, positive predictive value 70.6%, and negative predictive value 86.2%. Among NDI-derived CHD and CVD deaths, older age (odds ratios, 1.06 and 1.04 per 1-year increase) was associated with a higher probability of disagreement with the adjudicated cause of death, whereas among REGARDS adjudicated CHD and CVD deaths a history of CHD or CVD was associated with a lower probability of disagreement with the NDI-derived causes of death (odds ratios, 0.59 and 0.67, respectively)., Conclusions: The modest accuracy and differential performance of NDI-derived cause of death may impact CHD and CVD mortality statistics., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Aerobic exercise transiently lowers blood pressure. However, limited research has concurrently evaluated blood pressure and small arterial elasticity (SAE), an index of endothelial function, among African American (AA) and European American (EA) women the morning after (i.e., ≈22 h later) acute bouts of moderate-intensity continuous (MIC) and high-intensity interval (HII) exercise matched for total work. Because of greater gradients of shear stress, it was hypothesized that HII exercise would elicit a greater reduction in systolic blood pressure (SBP) compared to MIC exercise. After baseline, 22 AA and EA women initiated aerobic exercise training 3 times/week. Beginning at week 8, three follow-up assessments were conducted over the next 8 weeks at random to measure resting blood pressure and SAE. In total all participants completed 16 weeks of training. Follow-up evaluations were made: (i) in the trained state (TS; 8-16 weeks of aerobic training); (ii) ≈22 h after an acute bout of MIC exercise; and (iii) ≈22 h after an acute bout of HII exercise. Among AAs, the acute bout of HII exercise incited a significant increase in SBP (mm Hg) (TS, 121 ± 14 versus HII, 128 ± 14; p = 0.01) whereas responses (TS, 116 ± 12 versus HII, 113 ± 9; p = 0.34) did not differ in EAs. After adjusting for race, changes in SAE were associated (partial r = -0.533; p = 0.01) with changes in SBP following HII exercise. These data demonstrate an acute, unaccustomed bout of HII exercise produces physiological perturbations resulting in a significant increase in SBP that are independently associated with decreased SAE among AA women, but not EA women.

Objective: To identify approximately 500 cases of incident cognitive impairment (ICI) in a large, national sample adapting an existing cognitive test-based case definition and to examine relationships of vascular risk factors with ICI., Method: Participants were from the REGARDS study, a national sample of 30,239 African-American and White Americans. Participants included in this analysis had normal cognitive screening and no history of stroke at baseline, and at least one follow-up cognitive assessment with a three-test battery (TTB). Regression-based norms were applied to TTB scores to identify cases of ICI. Logistic regression was used to model associations with baseline vascular risk factors., Results: We identified 495 participants with ICI of 17,630 eligible participants. In multivariable modeling, income (OR 1.83 CI 1.27,2.62), stroke belt residence (OR 1.45 CI 1.18,1.78), history of transient ischemic attack (OR 1.90 CI 1.29,2.81), coronary artery disease(OR 1.32 CI 1.02,1.70), diabetes (OR 1.48 CI 1.17,1.87), obesity (OR 1.40 CI 1.05,1.86), and incident stroke (OR 2.73 CI 1.52,4.90) were associated with ICI., Conclusions: We adapted a previously validated cognitive test-based case definition to identify cases of ICI. Many previously identified risk factors were associated with ICI, supporting the criterion-related validity of our definition.

Background: Alterations in cardiovascular structure and function have been shown to precede the finding of elevated blood pressure., Methods: This study is part of the Hypertension Genetic Epidemiologic Network (HyperGEN) in which genetic and environmental determinants of hypertension were investigated in 5 geographical field centers. All nonhypertensive offspring (n = 1,035) were included from the entire HyperGEN study population that consists of 2,225 hypertensive patients and 1,380 nonhypertensive patients who had adequate echocardiographic left ventricular (LV) mass measurements. Participants were compared by self-declared race (African American and white)., Results: Nonhypertensive African American offspring were younger (aged 31 years vs. 38 years), more likely to be female, and had a higher body mass index (BMI) and higher systolic blood pressure (SBP) than their white counterparts. After adjusting for age, sex, SBP, pulse pressure (PP), BMI, diabetes status, and family effects, we observed statistically significant and potentially pathophysiological differences (all with P ≤ 0.001) with greater LV mass/height, relative wall thickness, and posterior wall thickness and with lesser midwall shortening, PP/stroke volume, and (PP/stroke volume)/fat-free body mass., Conclusion: This study shows that ethnic differences in hemodynamic and echocardiographic profiles exist in a large, population-based cohort of nonhypertensive offspring of hypertensive parents.

Background: Studies have shown that aspirin used for secondary prevention significantly reduces cardiovascular and stroke risk. The data for aspirin and primary prevention of cardiovascular disease, and in particular stroke, are less clear, especially among blacks., Objective: To evaluate prophylactic aspirin use and incident stroke in a large cohort of black and white participants., Methods: The Reasons for Geographic and Racial Differences in Stroke study is a national, population-based, longitudinal study of 30,239 African Americans and whites, older than 45 years. Participants with stroke at baseline were excluded, reducing the cohort to 27,219. Proportional hazard models were used to estimate the association of incident stroke with prophylactic aspirin use, adjusted for confounding factors. Separate analyses were performed for subjects who self-reported baseline aspirin use for primary prevention of vascular disease compared with those using aspirin use for other indications., Results: In all, 10,177 participants taking prophylactic aspirin were followed for a mean of 4.6 years. Univariate analysis showed an increased stroke risk for prophylactic aspirin use (hazard ratio [HR]: 1.37; 95% confidence interval: 1.16-1.62), but the association was attenuated (HR: 1.06; 95% CI: .86-1.32) with multivariable adjustment, adjusting for demographic factors (age, race, sex, and region), socioeconomic factors (income and education), perceived general health, cardiovascular disease (CVD) risk factors (hypertension, diabetes, dyslipidemia, cigarette smoking, and alcohol use), and finally the Framingham Stroke Risk Score (in a separate model). No racial, sex, or regional differences in the association were demonstrated., Conclusions: In this observational study, prophylactic aspirin use was not associated with risk of first stroke, and there were no sex, race, or regional differences., (Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Background: There are few available data on the epidemiology of prehypertension (preHTN). To determine racial, clinical, and demographic differences in the prevalence of preHTN and its cross-sectional association with vascular risk factors., Methods: Cross-sectional analysis of 5,553 prehypertensives, 20,351 hypertensive's, and 4,246 nonhypertensive participants (age ≥45), from a population-based national cohort study (REasons for Geographic And Racial Differences in Stroke (REGARDS) total population 30,239, of whom 30,150 had adequate blood pressure (BP) measurements) enrolled from January 2003-October 2007 with oversampling from the southeastern stroke belt, and black individuals. Baseline data were collected using a combination of telephone interview and in-home evaluation. preHTN was defined according to The Seventh Report of the Joint national Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) guidelines., Results: The prevalence of preHTN was associated with age and black race (62.9% in blacks compared to 54.1% in whites). A higher prevalence of preHTN was observed in obese individuals, self-reported heart disease; and, those with elevated high-sensitivity C reactive protein (hsCRP), diabetes, and microalbuminuria compared to those without these factors. Heavy alcohol consumption in white participants was associated with increased odds of preHTN (odds ratio (OR) = 1.32) but was even greater in black participants (OR = 2.27)., Conclusion: The prevalence of preHTN increased by age and African-American race. In addition, a higher prevalence of preHTN was observed with elevated hsCRP, diabetes, microalbuminuria, and those with heavy alcohol consumption compared to those without these factors.

Objectives: Among persons treated for hypertension, Blacks are more likely to have uncontrolled blood pressure compared to Whites. Few studies have focused on trust in physicians as a potential contributor to this disparity in blood pressure (BP) control. The primary objective of this study was to assess the relationship between trust in physicians and blood pressure control among Blacks and Whites being treated for hypertension., Design: Cross-sectional analysis of baseline data collected from the REasons for Geographic And Racial Differences in Stroke cohort, a US national, population-based cohort study. Participants were recruited by telephone from 2003-2007, completed a telephone survey, and had BP measured during an in-home visit., Participants: 2843 Black and White adults aged > 45 years with treated hypertension., Main Outcome Measures: Uncontrolled blood pressure was defined as systolic blood pressure > 140 mm Hg or diastolic blood pressure > 90 mm Hg. For participants with diabetes, renal disease, or self-reported previous myocardial infarction, uncontrolled blood pressure was defined as systolic blood pressure > 130 mm Hg or diastolic blood pressure > 80 mm Hg., Results: Trust in physicians was not associated with uncontrolled blood pressure in either unadjusted (odd ratio [OR] 1.07; 95% confidence interval [CI) 0.92, 1.25) or adjusted analyses (OR 0.97; 0.83, 1.14). Both Black race (OR 1.58; 1.36, 1.84) and imperfect medication adherence (OR 1.56; 1.31,1.86) were associated with higher odds of uncontrolled blood pressure., Conclusions: Trust in physicians was not related to blood pressure control among Blacks and Whites with treated hypertension in this sample. The racial disparity in blood pressure control was not completely explained by trust in physicians or medication adherence, and a better understanding of the mechanisms leading to this disparity is needed.

Background: Statin use and type have been variably associated with impaired or improved cognitive performance., Hypothesis: To assess the association of statin use and type (lipophilic vs hydrophilic) and cognitive impairment., Methods: Cross-sectional analysis of 24 595 participants (7191 statin users and 17 404 nonusers) age > or = 45 years, from a population-based national cohort study (Reasons for Geographic And Racial Differences in Stroke) enrolled between January 2003 and October 2008, with oversampling from the southeastern Stroke Belt and African Americans. Statin use and type were documented in participants' homes by a trained health professional. Cognitive performance was assessed with a prior validated instrument of global cognitive status (Six-Item Screener). Cognitive impairment was defined as a score of < 4., Results: Overall, an association of cognitive impairment and statin use was observed (8.6% of users vs 7.7% of nonusers had cognitive impairment, P = 0.014); but, after adjusting for variables known to be associated with cognition (age, gender, race, income, education level, and cardiovascular disease), the association was attenuated (odds ratio [OR]: 0.98, confidence interval [CI]: 0.87-1.10). No association was observed between statin type (lipophilic vs hydrophilic) and cognition (OR: 1.03, CI: 0.86-1.24), and there were no regional differences in cognitive impairment in statin users (8% in the Stroke Belt and 7.9% in other regions, P = 0.63)., Conclusions: Statin use and type were marginally associated with cognitive impairment. After adjusting for known variables that affect cognition, no association was observed. No regional differences were observed. This large study found no evidence to support an association between statins and cognitive performance., (Copyright 2010 Wiley Periodicals, Inc.)

Context: Aspirin use may reduce the risk of stroke and coronary heart disease. Differential use for vascular prophylaxis may contribute to racial and geographic disparities in stroke and coronary heart disease morbidity or mortality., Objective: To assess the prevalence and predictors of aspirin use for primary prophylaxis of stroke in the general population free of clinically diagnosed stroke or coronary heart disease., Design and Setting: Cross-sectional analysis of 16,908 participants (age 45 or greater), from a population-based national cohort study (REasons for Geographic And Racial Differences in Stroke) enrolled from February 2003-August 2006 with oversampling from the southeastern Stroke Belt and African Americans. Individuals with a prior stroke or coronary heart disease, or regular use of aspirin for pain relief were excluded from analyses., Main Outcome Measures: Aspirin use and reasons for use were assessed using a computer-assisted telephone interview., Results: Prophylactic aspirin use was substantially higher among whites (34.7%) than African Americans (27.2%; p<0.0001). There was a higher prevalence of aspirin use for prophylaxis in the Stroke Belt (32.1%) than in the rest of the nation (30.8%; p=0.07). After adjustment for measures of socio-economic status, the odds ratio of aspirin use in the rest of the nation compared to Stroke Belt was 0.90 (95% CI 0.84-0.97). There was a higher likelihood of prophylactic aspirin use among participants who were white, male, older, past cigarette smokers, or of higher socio-economic status (higher income or education)., Conclusions: In this study, aspirin use to prevent stroke and coronary heart disease was higher among whites than African Americans, raising the possibility that differential aspirin use could contribute to the racial disparities in vascular disease mortality. Counter to our hypothesis, aspirin use was more common in the Stroke Belt than the rest of the country, so differential aspirin use in the Stroke Belt is unlikely to contribute to geographic disparities in stroke.