Combination drug therapy for familial combined hyperlipidemia.

STUDY OBJECTIVE

To compare the efficacy of gemfibrozil and colestipol with gemfibrozil and lovastatin in patients with familial combined hyperlipidemia.

DESIGN

A prospective, randomized trial.

SETTING

An outpatient clinical research center in a tertiary care center.

PATIENTS

Seventeen patients with familial combined hyperlipidemia documented by studies of first-degree relatives; nine patients with type 2b hyperlipoproteinemia, and eight patients with type 4 hyperlipoproteinemia.

INTERVENTIONS

Baseline lipid, lipoprotein, and apolipoprotein levels were obtained during control periods on diet alone and on gemfibrozil therapy. Patients then received gemfibrozil and colestipol or gemfibrozil and lovastatin in a randomized order.

MEASUREMENTS AND MAIN RESULTS

In patients with type 2b hyperlipoproteinemia, gemfibrozil alone significantly reduced total cholesterol by 11%, and low density lipoprotein (LDL)-apolipoprotein B by 18%, did not change LDL-cholesterol, and raised high density lipoprotein (HDL)-cholesterol levels by 26%. Addition of either colestipol or lovastatin reduced LDL-cholesterol levels by 17% and 25%, respectively, compared to gemfibrozil alone. However, colestipol mitigated the HDL-cholesterol raising effect of gemfibrozil and did not further reduce LDL-apolipoprotein B levels. In contrast, addition of lovastatin caused an additional reduction of LDL-apolipoprotein B 19% compared with gemfibrozil alone. In patients with type 4 hyperlipoproteinemia, gemfibrozil alone reduced triglycerides by 40%, raised HDL-cholesterol by 26%, and increased LDL-cholesterol levels by 29%. The addition of either colestipol or lovastatin reduced LDL-cholesterol levels by 34% and 33%, respectively (compared with gemfibrozil alone), but greater reductions of LDL-apolipoprotein B (30% with lovastatin compared with 15% with colestipol, compared with gemfibrozil alone), and increases in HDL-cholesterol levels (8% increase with lovastatin compared with 10% decrease with colestipol, compared to gemfibrozil alone) were seen with the lovastatin combination.

CONCLUSIONS

Although gemfibrozil with either colestipol or lovastatin favorably altered lipoprotein levels in patients with hypertriglyceridemia and familial combined hyperlipidemia, the combination of gemfibrozil and lovastatin appeared superior overall.