Objective: To investigate the relationship between sex hormones and metabolic syndrome (MS), as well as its components in elderly men.
Methods: 1 505 elderly men (≥60 years old, mean age 75.4±9.7 years old) who participated in a routine health screening examination in PLA general hospital from May to June in 2012 were enrolled in this cross-sectional study. Serum lipids, glucose and sex hormones were measured along with body height, weight and blood pressure. Free testosterone (FT) and bioavailable testosterone (BT) were calculated. The correlation of serum sex hormones with the presence of MS and its components were analyzed.
Results: The prevalence of MS was 21.7% (326/1 505) in this study. Elderly men with MS had lower levels of sex hormone-binding globulin (SHBG), total testosterone (TT), FT and BT than those without MS. The levels of SHBG, TT, FT and BT were significantly lower in the overweight/obesity group, hyperglycemia group and dyslipidemia group than those in the respective control groups (P<0.05). Logistic regression analysis showed that the SHBG level was an independent risk factor for MS in elderly men(OR=0.977, 95%CI: 0.964-0.989, P<0.001), while the levels of TT, FT and BT were not associated with MS. The prevalence of MS gradually increased with decreasing of SHBG values (P<0.001). When comparing subjects in the lowest and highest quartile of SHBG, the former group demonstrated a 2.13-fold increase in the odds ratio for MS after adjusting for age, smoking, drinking and other sex hormone indices.
Conclusion: In elderly men, lower SHBG level, not TT, FT or BT may be an independent predictor for the prevalence of MS, in which the mechanism requires further studies.