Short answer: Not in the large trials. AIM-HIGH and HPS2-THRIVE added extended-release niacin to statin therapy in people with heart disease. Cholesterol numbers improved, but heart events did not fall, and HPS2-THRIVE found more serious side effects. The Zocor label says lipid-lowering doses of niacin (1 gram a day or more) with simvastatin raise the risk of muscle damage. Small doses in multivitamins are a different matter.
| Trial | People | Effect on cholesterol | Heart events |
|---|---|---|---|
| AIM-HIGH (2011) | 3,414 with heart disease; niacin 1,500 to 2,000 mg a day | HDL up from 35 to 42 mg/dL; triglycerides and LDL down | 16.4% vs 16.2% on placebo; stopped early at about 3 years for lack of benefit |
| HPS2-THRIVE (2014) | 25,673 with vascular disease; niacin 2 g a day with laropiprant | LDL 10 mg/dL lower, HDL 6 mg/dL higher | 13.2% vs 13.7% on placebo; not a significant difference |
HPS2-THRIVE also found more serious problems with niacin: diabetes control worsened (3.7 percentage points more), new diabetes diagnoses rose (1.3 points), and there were more serious stomach, muscle, skin, infection and bleeding events. ODS adds that AIM-HIGH saw a higher risk of ischemic stroke with niacin, and that two 2017 reviews concluded niacin gives little if any protection from heart disease.
The Zocor (simvastatin) label (sections 5.1 and 7.1) says cases of myopathy and rhabdomyolysis, two kinds of muscle damage, have been seen when lipid-modifying doses of niacin (1 gram a day or more) were taken with simvastatin, and that the risk is greater in Chinese patients. In a study of people taking simvastatin 40 mg with extended-release niacin 2 g a day, myopathy occurred in 1.24% of Chinese patients.
The label says this combination is not recommended in Chinese patients, and for others to weigh the benefit against the muscle risk. It also says that in the same high-risk study, adding niacin gave no extra heart benefit.
ODS separates the two. The adult upper limit for niacin from supplements is 35 mg a day, set to avoid flushing. Doses used for cholesterol are 1,000 to 3,000 mg a day, far above that, and ODS lists side effects at those doses: low blood pressure that can lead to falls, fatigue, insulin resistance and higher blood sugar, stomach upset, vision changes, and liver damage, which is more likely with extended-release forms.
Nicotinamide (niacinamide) does not cause flushing but also does not lower cholesterol, ODS notes. A multivitamin with a small amount of niacin is not what the trials tested.
ODS says people taking diabetes medicines should have blood sugar watched if they take high-dose niacin, because doses of 1.5 g a day or more are most likely to raise it. Whether niacin has a place alongside a statin is a question for the prescriber. Dose Track can hold both on one list with notes, and other statin pairs are on red yeast rice and statins and grapefruit and medicines.
Read more on Dose Track: Cholesterol · Lipid panel · NMN vs nicotinamide riboside