The Saitama Postmenopausal
Lipid Intervention Study was a multicenter, uncontrolled, collaborative study that investigated tolerability and sex-related differences in the response of serum
lipids to
simvastatin administered for 12 months in 122 postmenopausal women and 55 men with serum total
cholesterol (TC) levels > or =220 mg/dL. With
simvastatin treatment, TC and
low-density lipoprotein cholesterol (
LDL-C) levels decreased significantly at 1 month in both groups, and these decreased levels were maintained throughout treatment (P < 0.001). A significant decrease in
triglyceride (TG) levels was also observed in both groups (P < 0.05). The mean percentage decreases in TC and
LDL-C levels in women (20% and 28%, respectively) were significantly greater than those in men (15% and 20%, respectively) (P < 0.001). Mean percentage changes in TC and
LDL-C levels in subgroups defined by stratification for baseline TC and
LDL-C levels were also greater in women. There were no sex-related differences in the percentage changes in TG or high-density
cholesterol levels, although the changes were influenced by baseline levels. Although the median dose of
simvastatin (milligrams per kilogram of
body weight) in women was significantly higher than in men (P < 0.001), the percentage changes in serum
lipids were not correlated with the doses of
simvastatin calibrated by
body weight. Adverse reactions occurred in 8 men and 7 women, so there appeared to be no significant sex-related difference. Eleven patients had abnormal laboratory values.
Simvastatin therapy for 12 months is well tolerated and effective for both women and men with
hypercholesterolemia. Sex-related differences occurred in the response to
simvastatin therapy of serum
lipids, especially TC and
LDL-C, with greater changes in
lipid levels occurring in women.