DECREASED SEX HORMONE-BINDING GLOBULIN PREDICTS NONINSULIN-DEPENDENT DIABETES-MELLITUS IN WOMEN BUT NOT IN MEN

Sex hormones may influence risk factors for noninsulin-dependent diabe tes mellitus (NIDDM). Decreased sex hormone-binding globulin (SHBG; an indirect measure of androgenicity) is associated with hyperinsulinemi a and insulin resistance. We measured SHBG concentrations in 58 subjec ts who later converted to diabetes and 107 subjects who remained normo glycemic throughout the 8 yr of follow-up of the San Antonio Heart Stu dy, a population-based study of diabetes and cardiovascular disease. A mong premenopausal women, SHBG concentrations (nanomoles per L) were s ignificantly lower in converters than in nonconverters (41.6 +/- 12.4 vs. 74.4 +/- 10.0; P = 0.004), but corresponding differences were not observed in postmenopausal women or in men. Since, however, analysis o f variance suggested no significant interaction between menopausal sta tus and conversion to NIDDM, we pooled pre- and postmenopausal women. Subsequent analysis indicated that SHBG concentrations predicted the d evelopment of NIDDM in women independently of glucose and insulin conc entrations. We conclude that increased androgenicity, as assessed by d ecreased SHBG concentrations, is an important independent risk factor for NIDDM in women.