Relation of Serum Levels of Sex Hormone Binding Globulin to Coronary Heart Disease in Postmenopausal Women

Hyperandrogenemia and low levels of sex hormone binding globulin (SHBG) are frequently found in women with metabolic syndrome, which is characterized by low high-density lipoprotein cholesterol, hypertriglyceridemia, obesity, and hyperinsulinemia. The specific contribution of these various factors to coronary heart disease (CHD) is controversial. The coronary angiograms of 87 consecutive postmenopausal women were evaluated using 2 semiquantitative scoring systems to estimate the extent of focal and diffuse vessel wall alterations. Fasting sera were analyzed for levels of glucose, lipids, insulin, leptin, dehydroepiandrosterone sulfate, testosterone, and SHBG. Obesity was assessed by measuring body mass index, waist-to-hip ratio, skinfold thicknesses, and body impedance. After adjusting for age, there were significant differences in 55 women with CHD compared with 32 women without CHD: higher levels of low-density lipoprotein cholesterol (159 +/- 51 vs 132 +/- 39 mg/dl), apolipoprotein B (121 +/- 33 vs 102 +/- 29 mg/dl), triglycerides (115 vs 91 mg/dl), and basal insulin (7.5 vs 4.6 mU/L), as well as lower levels of high-density lipoprotein cholesterol (59.9 +/- 18.0 vs 69.0 +/- 17.1 mg/dl), SHBG (44.6 vs 68.1 nmol/L) and the quantitative insulin sensitivity check index (0.66 +/- 0.41 vs 0.93 +/- 0.73). Multivariate analysis by logistic regression identified age (odds ratio [OR] 1.22, 95% confidence intervals [CI] 1.09 to 1.37), smoking (OR 11.46, 95% CI 2.56 to 51.39), SHBG (OR 0.98, 95% CI 0.96 to 0.99), and apolipoprotein B (OR 1.02, 95% CI 1.01 to 1.04) as independently associated with the presence of CHD. Thus, low plasma levels of SHBG are associated with CHD in women independently of insulin, obesity markers, and dyslipidemia.