The incidence of coronary heart disease (CHD) has been declining in the United States,¹ but this improvement appears to be lagging in blacks compared with whites.² To understand race-based patterns in contributions to risk over time, we investigated temporal trends in the prevalence of major risk factors and their associated hazards for CHD in a large sample of black and white adults living in 4 different communities and followed up over the last 2 decades.

We examined age-adjusted temporal trends in the population-attributable risk (PAR) of major CHD risk factors (hypertension, hypercholesterolemia, diabetes mellitus, smoking, and obesity) using data collected continuously from 14 766 participants (27% black, 56% women) in the multicenter ARIC study (Atherosclerosis Risk in Communities) who were originally free of CHD and followed up from 1987 to 2013.³ Risk factors were defined according to the following criteria: hypertension as systolic blood pressure (BP) ≥140 mm Hg, diastolic BP ≥90 mm Hg, or antihypertensive medication use; hypercholesterolemia as total cholesterol ≥200 mg/dL or cholesterol-lowering medication use; obesity as body mass index ≥30 kg/m²; diabetes mellitus as fasting glucose ≥126 mg/dL, nonfasting glucose ≥200 mg/dL, or glucose-lowering medication use; and, current smoking as self-reported active smoking within 1 year. We used a single time-to-event model that considered calendar days as the time scale and treated vital status and all covariates (including risk factors and age) as time updated while standardizing all results to referent age 65 …

在美国，冠心病（CHD）的发病率一直在下降[ ^1]，但与白人相比，黑人的这种改善似乎滞后。²为了了解基于种族的风险贡献模式随时间的推移，我们调查了生活在4个不同社区的大量黑人和白人成年人中主要风险因素及其对冠心病的危害的流行趋势，并在随访期间进行了随访。持续了20年。

我们使用从14 766名参与者（27％的黑人，56％的女性）中连续收集的数据，检查了主要CHD危险因素（高血压，高胆固醇血症，糖尿病，吸烟和肥胖）的人群归因风险（PAR）的年龄调整后的时间趋势。 ）的多中心ARIC研究（社区中的动脉粥样硬化风险）最初没有冠心病，并于1987年至2013年进行了随访^。3根据以下标准定义了危险因素：高血压是收缩压（BP）≥140 mm Hg，舒张压BP≥90 mm Hg，或使用降压药；高胆固醇血症，总胆固醇≥200 mg / dL或使用降胆固醇药物；体重指数≥30kg / m ^2的肥胖; 空腹血糖≥126mg / dL，非空腹血糖≥200mg / dL或使用降糖药物治疗的糖尿病；并且，当前吸烟是一年内自我报告的主动吸烟。我们使用了一个单一的事件发生时间模型，该模型将日历日作为时间尺度，并将生命状态和所有协变量（包括危险因素和年龄）视为时间更新，同时将所有结果标准化为65岁参照年龄……