Relationship of Lipoproteins to Cardiovascular Events The AIM-HIGH Trial (Atherothrombosis Intervention in Metabolic Syndrome With Low HDL/High Triglycerides and Impact on Global Health Outcomes)

Department of Medicine, Duke University Medical Center, Durham, NC. Electronic address: .
Journal of the American College of Cardiology (Impact Factor: 15.34). 07/2013; 62(17). DOI: 10.1016/j.jacc.2013.07.023
Source: PubMed

ABSTRACT In this secondary analysis of the AIM-HIGH trial, the objectives were to examine the relationship between niacin treatment, lipoproteins, and cardiovascular (CV) outcomes.
During 3-year follow-up in 3,414 patients with established CV disease and low HDL-C, combined niacin + LDL-lowering therapy did not reduce CV events versus LDL-lowering therapy alone.
Subjects taking simvastatin ± ezetimibe were randomized to extended-release (ER) niacin 1500-2000 mg or minimal immediate-release niacin (<150 mg) as placebo at bedtime. LDL-C in both groups was maintained from 40 to 80 mg/dL. Hazard ratios (HR) were estimated by Cox proportional hazards for relationships between lipoproteins and the composite endpoint of CV death, myocardial infarction, acute coronary syndrome, ischemic stroke, or symptom-driven revascularization.
CV outcomes were not associated with ER niacin in any baseline lipoprotein tertile. In a subset of patients in both the highest triglyceride (≥198 mg/dl) and lowest HDL-C (<33 mg/dl) tertiles, ER niacin showed a trend toward benefit (HR=0.74, p=0.073). In-trial LDL-C, nonHDL-C, and TC/HDL-C ratio were positively associated with CV events in the control group, but these relationships were absent in the ER niacin group.
Baseline lipoprotein tertiles did not predict differential benefit or harm with ER niacin added to LDL-lowering therapy, but a small dyslipidemic subgroup may benefit. ER niacin attenuated expected relationships of lipoprotein risk factors with CV events, raising the possibility that nonlipoprotein actions of niacin could impact risk.

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