Niacin didn’t reduce the incidence of major vascular events even though, once again, it decreased LDL and increased HDL more than placebo. Niacin increased the risk of serious adverse events 56% vs 53% (risk ratio [RR]=6; 95% CI, 3-8; number needed to harm [NNH]=35; 95% CI, 25-60), such as new onset diabetes (5.7% vs 4.3%; P<.001; NNH=71) and gastrointestinal bleeding/ulceration and other gastrointestinal disorders (4.8% vs 3.8%; P<.001; NNH=100).
A subsequent 2014 study examined the adverse events recorded in the AIM-HIGH4 study and found that niacin caused more gastrointestinal disorders (7.4% vs 5.5%; P=.02; NNH=53) and infections and infestations (8.1% vs 5.8%; P=.008; NNH=43) than placebo.7 The overall observed rate of serious hemorrhagic adverse events was low, however, showing no significant difference between the 2 groups (3.4% vs 2.9%; P=.36).
RECOMMENDATIONS
As of November 2013, the Institute for Clinical Systems Improvement recommends against using niacin in combination with statins because of the increased risk of adverse events without a reduction in CVD outcomes. Niacin may be considered as monotherapy in patients who can’t tolerate statins or fibrates based on results of the Coronary Drug Project and other studies completed before the era of widespread statin use.8
Similarly, American College of Cardiology/American Heart Association guidelines state that patients who are completely statin intolerant may use nonstatin cholesterol-lowering drugs, including niacin, that have been shown to reduce CVD events in RCTs if the CVD risk-reduction benefits outweigh the potential for adverse effects.9