Effects of ezetimibe added to on-going statin therapy on the lipid profile of hypercholesterolemic patients with diabetes mellitus or metabolic syndrome

SUMMARY

Objective: To conduct a post-hoc assessment of the lipid-modifying effects of adding the cholesterol absorption inhibitor, ezetimibe, to on-going statin therapy in patients with diabetes mellitus (DM) or metabolic syndrome (MetS).

Research design and methods: This was a post-hoc analysis of data from a randomized, double-blind, placebo-controlled trial designed to evaluate the low-density lipoprotein cholesterol (LDL-C)-lowering efficacy and safety of adding ezetimibe 10?mg/day versus placebo to ongoing, open-label statin treatment for 8 weeks in hypercholesterolemic patients. Qualifying LDL-C levels and target LDL-C goals were based on National Cholesterol Education Program risk categories. The DM subgroup were patients who entered the study with a prior diagnosis of DM. Patients were classified as having MetS if they met 3 or more of the following criteria at baseline: triglycerides (TG) ≥ 150?mg/dL (1.69 mmol/L); high-density lipoprotein cholesterol (HDL-C) < 40?mg/dL (1.04 mmol/L) for men or < 50?mg/dL (1.29 mmol/L) for women; fasting serum glucose (FSG) ≥ 110?mg/dL (≥ 6.1 mmol/L); a diagnosis of hypertension or taking hypertension medication or blood pressure ≥ 130/ ≥ 85 mmHg; waist circumference > 88?cm (women) or > 102?cm (men). DM patients were excluded from the MetS subgroup analysis.

Main outcome measures: The objectives were to assess the effects of treatment on plasma concentrations of LDL-C and other lipid variables, and on the percentage of patients achieving LDL-C target levels at the end of the study.

Results: Of 769 patients enrolled in the original study, there were 191 (24.8%) with DM and 195 (25.4%) with MetS. Regardless of subgroup, ezetimibe + statin was significantly more effective than statin alone at lowering plasma levels of LDL-C, non-HDL-C, total cholesterol, apolipoprotein B, and triglycerides (between-group p < 0.001 for all). For all lipid parameters, the relative treatment effects were generally consistent regardless of DM or MetS status. Significantly more ezetimibe than placebo patients in all subgroups achieved prespecified LDL-C goals (?p < 0.001 for all), and although more patients in the DM and MetS groups, respectively, achieved the goal compared with their non-DM and non-MetS counterparts 83.6% (DM) versus 67.2 (non-DM) and 71.8% (MetS) versus 65.6% (non-MetS)], these differences were not significant after adjusting for differences in baseline LDL-C levels. Ezetimibe was well-tolerated and had a favorable safety profile in all subgroups.

Conclusions: The co-administration of ezetimibe with statins, a therapeutic regimen that inhibits both the absorption and synthesis of cholesterol, offers a well-tolerated and efficacious treatment to lower LDL-C in patients with DM and MetS.