Abstract 14578: Low Medication Adherence and Uncontrolled LDL-Cholesterol Among ‰High Risk Us Adults Taking Statins: Data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Abstract

Data from clinic-based populations and large health maintenance organizations suggest low adherence to statins is common among people with a history of coronary heart disease (CHD). Few data on adherence are available from community-based samples. We studied medication adherence among adults with CHD or risk equivalents taking statins in the population-based Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. Between 2003 and 2007, 30,239 black and white US adults ≥ 45 years of age from across the continental US completed a telephone interview, in-home study examination including phlebotomy after an overnight fast, and self-administered questionnaires. CHD or risk equivalents were defined by a history of myocardial infarction (self-report or detected on electrocardiogram), coronary revascularization, stroke, aortic aneurysm or a 10-year risk for CHD ≥ 20% based on measured risk factors and the Framingham risk equation. Statin use was determined through pill bottle review and adherence determined using the 4-item Morisky Medication Adherence Scale (MMAS). There were 4,936 REGARDS participants with CHD or a risk equivalent taking statins. Overall, 68%, 25%, 5%, and 2% of participants had MMAS scores of 0 (best adherence), 1, 2, and 3 or 4 (worst adherence). Among statin users, a graded association was present between worse adherence and higher fasting LDL-cholesterol levels and a lower percentage achieving their ATP-III defined LDL-cholesterol goal (each p-trend<0.001, Figure). After multivariable adjustment, blacks (prevalence ratio: 1.38, 95% CI: 1.09, 1.74), those with depression (1.68, 95% CI: 1.31, 2.15) and with a history of CHD (1.39, 95% CI: 1.11, 1.74) were more likely to have low adherence (MMAS-4 score ≥ 2). In this nationwide community-based sample of high risk US adults, low adherence maintained a strong and graded association with uncontrolled LDL-cholesterol.