Niacin improves lipid profile but not endothelial function in patients with coronary artery disease on high dose statin therapy

► Low HDL correlates with cardiovascular risk and occurs despite optimal statin use. ► We present the effect of niacin on endothelial function with low LDL cholesterol. ► A 3 month placebo controlled randomized crossover study design of 66 patients. ► Addition of Niacin to atorvastatin significantly reduced LDL and increased HDL levels. ► Niacin did not effect endothelial or microvascular function compared with placebo.