Relation of Cardiovascular Events and Deaths to Low-Density Lipoprotein Cholesterol Level Among Statin-Treated Patients With Atherosclerotic Cardiovascular Disease

Abstract

This study describes subsequent cardiovascular events and deaths by low-density lipoprotein cholesterol (LDL-C) level in patients with atherosclerotic cardiovascular disease (ASCVD) receiving moderate- to high-intensity statins. Olmsted County, Minnesota residents with index ASCVD (myocardial infarction, unstable angina, coronary revascularization, ischemic stroke or transient ischemic attack) occurring between 2005 and 2012 were identified, and those with a prescription for a moderate- or high-intensity statin and an LDL-C measurement in the 90 days after index were included. Cox regression models were used to examine associations between LDL-C, modeled as a time-dependent variable, and a composite outcome of subsequent cardiovascular events or all-cause death. Among 1,854 patients with ASCVD (mean [SD] age 66.0 [13.3] years, 63.6% male), a total of 1,241 events were observed from index ASCVD through follow-up (median of 5.9 years). The rate (95% confidence interval) per 100 person-years was 11.26 (10.64 to 11.91). Starting follow-up 90 days after index ASCVD event, the rates per 100 person-years were 10.51 (9.57 to 11.52), 9.57 (8.66 to 10.55), and 11.40 (9.96 to 12.98) for LDL-C <70, 70-<100 and ≥100 mg/dl, respectively. After adjustment for age, sex, and previous diagnoses of ASCVD, diabetes, hypertension, heart failure, and chronic kidney disease, the hazard ratio for cardiovascular event and/or death was significantly higher for patients with LDL-C ≥100 mg/dl than those with LDL-C <70 mg/dl (1.31 [1.08 to 1.59]). In conclusion, in patients with ASCVD, subsequent cardiovascular events occur at a high rate and the rates are highest in patients with LDL-C ≥100 mg/dl suggesting unmet treatment needs even in patients receiving moderate- to high-intensity statins.