The effect of hormone replacement therapy on cardiovascular risk factors in type 2 diabetes: a randomized controlled trial.

BACKGROUND Postmenopausal women with diabetes are at high risk for cardiovascular disease, compared with their nondiabetic counterparts. Combined continuous hormone replacement therapy (HRT) is associated with improvements in serum lipoprotein levels in nondiabetic women; however, the effect in women with diabetes has not been determined. We evaluated the effect of combined continuous HRT on lipoprotein and coagulation factor concentrations and glycemic control in postmenopausal women with type 2 diabetes mellitus. METHODS In a randomized controlled crossover study, 61 subjects received combined continuous HRT or placebo. Each treatment phase was of 6 months' duration, with an 8-week washout phase between treatment phases. RESULTS Total cholesterol concentration decreased by 7% (95% confidence interval [CI], 4%-11%) during HRT. For low-density lipoprotein concentration, the mean decrease with HRT was 12% (95% CI, 6%-17%). Apolipoprotein B levels decreased in keeping with the reduction in low-density lipoprotein cholesterol concentrations. There were no significant changes in concentrations of high-density lipoprotein, its subfractions, or triglycerides. Lipoprotein(a) and fibrinogen concentrations were reduced by 21% (95% CI, 10%-31%) and 8% (95% CI, 2%-13%), respectively, with HRT. Fructosamine concentrations declined by 5% (95% CI, 2%-9%) during HRT. CONCLUSIONS In postmenopausal women with type 2 diabetes mellitus, combined continuous HRT has beneficial effects on lipoprotein concentrations and improves some markers of coagulation and glycemic control.