Abstract 208: No Independent Association Between Extended-Release Niacin (ERN) Therapy and Ischemic Stroke in Patients with Established Cardiovascular Disease: A Detailed Analysis from the AIM HIGH Trial
Background: Statins reduce cardiovascular (CV) events and stroke by 20-25% in both patients with established cardiovascular disease (CVD) and in asymptomatic patients at high risk for CVD. Meta-analyses also show that niacin reduces major CV events by 25% and stroke by 27%. In AIM HIGH, which evaluated the addition of extended-release niacin (ERN) to simvastatin in patients with established CV disease and low baseline levels of HDL-C, we observed an unexpected increased rate of ischemic stroke in those randomized to ERN. The present analysis explores possible reasons for the observed numerical excess of ERN-associated stroke.
Methods and Results: Among 3,414 patients (85% male; mean age: 64±9 years) randomized to simvastatin + ERN (1,500-2,000mg/day or matching placebo to achieve an on-treatment LDL-C target of 40-80mg/dL), there was no difference in the trial’s composite primary endpoint at a mean 36-month follow-up. This included 50 fatal or non-fatal ischemic strokes, of which 18 (1.85%) occurred in the placebo arm and 32 (2.3%) in the niacin arm (age-adjusted HR 1.78; 95% CI 1.00-3.17, p=0.050). Multivariate step-wise analyses showed strong associations between ischemic stroke risk and age > 65 (HR 3.60 95% CI 1.83-7.09, p=0.0002) and history of stroke/TIA/carotid disease (HR 2.19 95% CI 1.23-3.90, p=0.0075), a moderate association with Lp(a) (HR 2.80, 95%CI 1.25 - 6.27, p=.012 comparing the middle to the lowest tertile), but an insignificant association between ischemic stroke and ERN (HR 1.74 95% CI .97-3.11, p=0.063).
Conclusion: Although there was a numerical excess in ischemic strokes associated with the addition of ERN to simvastatin, the number of events was small and multivariable analysis accounting for known risk factors revealed no significant association between niacin treatment and subsequent ischemic stroke risk.
- © 2012 by American Heart Association, Inc.