The role of niacin in raising high-density lipoprotein cholesterol to reduce cardiovascular events in patients with atherosclerotic cardiovascular disease and optimally treated low-density lipoprotein cholesterol Rationale and study design. The Atherothrombosis Intervention in Metabolic syndrome with low HDL/high triglycerides: Impact on Global Health outcomes (AIM-HIGH).

BACKGROUND: The aim of this study was to test the hypothesis that patients with atherosclerotic cardiovascular (CV) disease optimally treated on a statin but with residual atherogenic dyslipidemia (low high-density lipoprotein cholesterol [HDL-C] and high triglycerides) will benefit from addition of niacin with fewer CV events compared with placebo. Statin monotherapy trials have found 25%-35% CV risk reduction relative to placebo, leaving significant residual risk. Patients with atherogenic dyslipidemia have substantially increased CV risk.

METHODS: Participants were men and women with established CV disease and atherogenic dyslipidemia. Lipid entry criteria varied by gender and statin dose at screening. All participants received simvastatin (or simvastatin plus ezetimibe) at a dose sufficient to maintain low-density lipoprotein cholesterol (LDL-C) 40-80 mg/dL (1.03-2.07 mmol/L). Participants were randomized to extended-release niacin or matching placebo. The primary end point was time to occurrence of the first of the following: coronary heart disease death, nonfatal myocardial infarction, ischemic stroke, hospitalization for acute coronary syndrome, or symptom-driven coronary or cerebral revascularization. This event-driven trial will have 85% power to show a 25% reduction in primary event frequency after 850 patients have experienced a primary outcome event.

RESULTS: AIM-HIGH completed enrollment in April 2010. Follow-up is expected to continue through 2012.

SUMMARY: AIM-HIGH was designed to determine whether treating residual dyslipidemia with niacin further reduces cardiovascular events in patients with CV disease on a statin at target levels of low-density lipoprotein cholesterol.