Associations of adiponectin with sex hormone-binding globulin levels in aging male and female populations

Background: Changes with aging in serum gonadal hormones, sex hormone-binding globulin (SHBG) and adiponectin, which are involved in insulin resistance and metabolic syndrome, are different in men and women. We examined the relationships of serum adiponectin concentrations with serum concentrations of hormones and SHBG in men and women. Methods: One hundred fifty-four men and 180 women aged from 50 to 85 years were included in the cross-sectional study. Serum concentrations of testosterone, estradiol, dehydroepiandrosterone-sulfate, SHBG and adiponectin were measured in men and women. Results: Serum adiponectin concentration showed a significant positive correlation with serum SHBG concentration in men and women (r = 0.404, p < 0.0001 and r = 0.348, p < 0.0001, respectively). Multiple regression analysis also showed that SHBG was the significant predictor for adiponectin in men and women. Serum adiponectin concentration in men showed a significant positive correlation with total testosterone concentration, but that in women was not significantly correlated with total testosterone concentration. Both adiponectin and SHBG concentrations in men (r = - 0.222, p = 0.0051 and r = - 0.334, p < 0.0001, respectively) and women (r = - 0.281, p = 0.0014 and r = - 0.251, p = 0.0048, respectively) showed significant negative correlations with the homeostasis model assessment (HOMA) index. Conclusion: Correlations between adiponectin and SHBG were significantly positive in both men and women, and both adiponectin and SHBG might be involved in insulin resistance in both sexes.