The relationship of total and free estrogens and sex hormone-binding globulin with lipoproteins in women.

To determine whether there was a significant relationship between circulating lipids or lipoproteins and circulating estrogens or sex hormone-binding globulin (SHBG) in pre- and premenopausal women, 352 women were chosen randomly from communities in Eastern Massachusetts. These women had nonfasting blood samples drawn and analyzed for total cholesterol, high density lipoprotein cholesterol (HDL-C), HDL-2, HDL-3, apolipoprotein-A-I (apo-A-I), apo-B, triglycerides (TG), estrone, estradiol (E2), free E2, SHBG, and FSH. In addition, their body mass index (BMI; wt/ht2) was calculated, and a history of smoking, ethanol intake, current medication use, and the date of their last menstrual period was obtained. When the women were grouped according to the months from their last menses (less than 1, 1-3, and 4-11 months), those 4 months or longer since last menses had significantly lower E2 concentrations and significantly greater total cholesterol and FSH concentrations than the other two groups. However, when regressed on hormones, BMI, ethanol intake, and last menstrual period, total cholesterol was significantly related only to the time from last menses; TG, HDL-C, HDL-2, and apo-A-I were related to SHBG. Relationships between the lipids, with the exception of cholesterol and apo-B, were also noted with BMI and/or ethanol. Apo-B was related to the time from last menses. Differences in circulating estrogens appeared to be related only minimally, if at all, to the differences in total cholesterol that are seen in perimenopausal women. The relationships between lipids and lipoproteins and SHBG are probably epiphenomena as a result of similar sites of synthesis. Changes in lipids and lipoproteins that are seen at the time of the menopause are probably multifactorial in origin.