Purpose: This prospective study was undertaken to evaluate the effects of gemfibrozil on the lipoprotein profile of patients with familial dysbetalipoproteinemia (type III hyperlipoproteinemia).
Patients and methods: Eight patients with well-defined familial dysbetalipoproteinemia associated with the apolipoprotein (apo) E2/2 phenotype were treated with gemfibrozil (Lopid) at a dose of 600 mg twice daily for a period of 10 months. Blood samples were taken at baseline, after 4 and 5 weeks, after 3 months, and after 10 months. The separation of serum lipoprotein (sub)fractions was performed by a recently developed density gradient ultracentrifugation technique.
Results: After 4 weeks of gemfibrozil therapy, the concentrations of serum total cholesterol and serum total triglyceride had decreased by 45% (from 11.87 to 6.51 mmol/L, p < 0.01) and by 63% (from 6.08 to 2.23 mmol/L, p < 0.001), respectively. The cholesterol concentrations of very-low-density lipoprotein-1 (VLDL1) (large VLDL), VLDL2 (small VLDL), and intermediate-density lipoprotein (IDL) had decreased significantly by 73%, 74%, and 34%, respectively. The low-density lipoprotein (LDL)-cholesterol level remained unchanged, whereas the particle size of LDL showed a small but significant increase (from 24.09 nm to 24.43 nm, p < 0.01). The concentrations of high-density lipoprotein (HDL)-cholesterol, apo A-I, and apo A-II had increased significantly by 23%, 13%, and 29%, respectively. Only minor changes in the composition of the lipoprotein (sub)fractions were observed. After 3 months of treatment with gemfibrozil, the concentrations of serum total cholesterol and serum total triglyceride were 5.95 mmol/L and 2.06 mmol/L, respectively, and after 10 months of treatment with gemfibrozil, the concentrations of serum total cholesterol and serum total triglyceride were 6.19 mmol/L and 2.27 mmol/L, respectively.
Conclusion: Gemfibrozil treatment in patients with familial dysbetalipoproteinemia resulted in a marked reduction of the concentrations of large VLDL, small VLDL, and IDL, and an increase in the levels of HDL, apo A-I, and apo A-II. These changes are considered to exert an antiatherosclerotic effect in these patients.