HDL-C Response Variability to Niacin ER in US Adults.

Background. Niacin is the most effective treatment currently available for raising HDL-C levels. Objective. To evaluate if gender and baseline lipid levels have an effect on the HDL-C response of niacin ER and to identify factors that predict response to niacin ER at the 500 mg dose. Material and Methods. The change in HDL-C effect between baseline and follow-up levels was quantified in absolute change as well as dichotomized into high versus low response (high response was defined as an HDL-C effect of >15% increase and low response was HDL-C <5%) in a sample of 834 individuals. Results. Both males and females with low HDL-C levels at baseline exhibited a response to treatment in the multivariate model (males, HDL-C <40 mg/dL: OR = 5.18, 95% CI: 2.36-11.39; females, HDL-C <50 mg/dL: OR = 5.40, 95% CI: 1.84-15.79). There was also a significant difference in the mean HDL-C effect between baseline and follow-up HDL-C levels in the 500 mg niacin ER dose group for both males (mean HDL-C effect = 0.08, P < 0.001) and females (mean HDL-C effect = 0.10, P = 0.019). Conclusion. Baseline HDL-C levels are the biggest predictor of response to niacin ER treatment for both males and females among the factors evaluated.