The New England Journal of Medicine has published the results of the AIM-HIGH study. This study aimed to assess the cardiovascular benefits of extended-release niacin (nicotinic acid) added to simvastatin to raise low levels of HDL cholesterol.
The study recruited 3,414 patients who were at least 45 years old, had a history of cardiovascular disease, low levels of HDL and high levels of triglycerides. All participants received simvastatin at a dose of 40mg or 80mg per day with ezetimibe 10mg daily added in to achieve a target LDL cholesterol of 1.03 to 2.07 mmol/L. Participants were then randomly assigned to extended-release niacin, 1500 to 2000 mg per day, or matching placebo. The primary outcome of the study was a composite of death from coronary heart disease, nonfatal myocardial infarction, ischemic stroke, hospital admission for an acute coronary syndrome, or symptom-driven coronary or cerebral revascularisation.
The trial was stopped after a mean follow-up period of 3 years owing to a lack of efficacy. At two years, treatment with extended-release niacin had significantly increased the median level of HDL from 0.91mmol/L to 1.08mmol/L. Triglyceride levels were also significantly reduced from 1.85mmol/L to 1.38mmol/L. Despite these favourable changes there was no significant difference in the primary outcome which was found to have a hazard ratio of 1.02 (95% confidence interval 0.87 - 1.21, P=0.79).
The authors of the study conclude that, "Among patients with atherosclerotic cardiovascular disease and LDL cholesterol levels of less than 1.81 mmol/L, there was no incremental clinical benefit from the addition of niacin to statin therapy".
Action: In patients with stable cardiovascular disease, intensifying treatment with niacin to increase HDL confers no cardiovascular benefits. In such patients any decision to intensify treatment should take into account current guidelines, patient preference and a consideration of the risks and benefits.