Is the Response of Serum Lipids and Lipoproteins to Postmenopausal Hormone Replacement Therapy Modified by ApoE Genotype?

Postmenopausal hormone replacement therapy (HRT) has favorable effects on the serum lipid profile, and it also decreases the risk of cardiovascular diseases. The apolipoprotein E genotype has influence on serum levels of lipids and lipoproteins; apoE allele epsilon 4 (apoE4) is associated with high total and LDL cholesterol levels. Genotype also influences the lipid responses to treatment with diet and statins, but the effect of HRT in different apoE genotypes is unknown. We studied the effects of HRT on the concentrations of serum lipids in apoE4-positive early postmenopausal women (genotypes 3/4 and 4/4) compared with apoE4-negative women (genotypes 2/3 and 3/3) in a population-based, prospective 5-year study. In all, 232 early postmenopausal women were randomized into 2 treatment groupsan HRT group (n=116), which received a sequential combination of 2 mg estradiol valerate (E2 Val) from day 1 to 21 and 1 mg cyproterone acetate (CPA) from day 12 to 21 (Climen), and a placebo group (n=116), which received 500 mg/d calcium lactate. Serum concentrations of total, LDL, and HDL cholesterol and triglycerides were measured at baseline and after 2 and 5 years of treatment. A total of 154 women completed the final analysis. During the follow-up period, serum total cholesterol and LDL cholesterol concentrations decreased in the HRT group in apoE4-negative women (8.1% and 17.1%, respectively; P