Effectiveness and tolerability of adding ezetimibe to niacin-based regimens for treatment of primary hyperlipidemia

To determine the effectiveness and tolerability of adding ezetimibe, 10 mg daily, to niacin-based regimens for dyslipidemia.

We conducted a retrospective review of medical records of 53 patients in 2 lipid clinics who received ezetimibe as add-on therapy to stable doses of niacin and other lipid medications. Mean percentage changes of lipoprotein cholesterol and triglyceride levels were determined. Safety and tolerability measures included adverse events, serum hepatic transaminases, and hemoglobin A1c (in patients with diabetes).

Most study subjects (81%) had established atherosclerotic disease. The niacin formulation was extended-release in 31 patients (58%), immediate-release in 17 (32%), and slow-release in 5 (9%). Most patients (75%) were also taking a statin. Add-on ezetimibe therapy yielded mean reductions of 18% for total cholesterol (P<0.001), 25% for low-density lipoprotein (LDL) cholesterol (P<0.001), and 17% for triglycerides (P<0.001). High-density lipoprotein (HDL) cholesterol did not change significantly (+2%). Only 7 patients (13%) met Adult Treatment Panel III (ATP III) LDL cholesterol goals before the addition of ezetimibe, but 24 (45%; P<0.001 compared with baseline) attained these goals after addition of ezetimibe to the therapeutic regimen. Ezetimibe effectiveness did not correlate with the baseline dose of niacin or the dose/efficacy of the statin used. The addition of ezetimibe to niacin-based therapy for dyslipidemia was well tolerated. No patient had clinically significant elevations in hepatic enzyme or hemoglobin A1c levels or discontinued the ezetimibe therapy permanently.

In our study, the addition of ezetimibe to niacin-based regimens lowered the LDL cholesterol level by 25% and did not change the level of HDL cholesterol. This combination can be useful in multidrug regimens for high-risk patients with dyslipidemia who are not achieving ATP III treatment goals.