Lower total testosterone independently associated with insulin resistance in older men
Document Actions
Low levels of sex hormones are associated in both genders with central adiposity, decreased skeletal muscle mass, insulin resistance and increased risk for metabolic syndrome and/or type 2 diabetes. This cross-sectional study was designed to investigate whether lower testosterone or sex hormone-binding globulin (SHBG) was associated with insulin resistance, independently of central obesity measures, in 2470 nondiabetic men aged ≥70 years. Insulin resistance was assessed using homeostatic model (HOMA2-IR) assessment. Total testosterone, free testosterone and SHBG declined progressively across increasing quintiles of HOMA2-IR, correlating inversely with log HOMA2-IR. After adjusting for body mass index, waist circumference, and other confounding factors, total testosterone, but not SHBG, was independently associated with log HOMA2-IR. Total testosterone <8 nmol/L was associated with HOMA2-IR in the highest quintile as was total testosterone ≥8 and <15 nmol/L. In conclusion, testosterone levels in the low to normal range are associated with insulin resistance, independently of central obesity measures. Further studies would be necessary to investigate whether interventions that raise testosterone levels in men with reduced insulin sensitivity may provide clinical benefit.
Abstract
