Testosterone Level and Risk of Diabetes: Follow-Up Study

Background: Epidemiological studies have documented an inverse relationship between testosterone levels and risk of cardiovascular disease. The present study aimed to explore the association between testosterone levels and risk of developing diabetes mellitus from 108 middle-aged men with no history of medical diseases. Methods: Data regarding the age of subjects, smoking, alcohol consumption, waist-to-hip ratio, and family history of cardiovascular disease were collected at the time of inclusion. Testosterone levels were also measured. 15 years later the medical history of the men was reviewed to record the development of medical incidents with references to diabetes mellitus. Two groups of men were identified based on testosterone levels: hypogonadal (testosterone ≤12 nmol/L) and eugonadal (testosterone >12 nmol/L). Results: In total, 10 (9.0%) out of 108 men developed diabetes during the 15-year follow-up period, of whom 6 (16%) out of 37 and 4 (6%) out of 71 were men in the hypogonadal and eugonadal cohorts respectively (p=0.08). Using Cox proportional hazards regression analysis, the adjusted risk for diabetes was significantly lower in eugonadal men compared to hypogonadal men (adjusted hazard ratio=0.236; 95% CI=0.062–0.898; P=0.03). Conclusion: Our results showed a significant increased risk of diabetes in men with low testosterone levels compared to men with normal testosterone.