Testosterone concentrations in diabetic and nondiabetic obese men.

Objective: To determine the prevalence of subnormal testosterone concentrations in patients with obesity and with type 2 diabetes in a primary care clinic population. Research Design and Methods: FT concentrations of 1849 men(1451 non-diabetic and 398 diabetic) in the Hypogonadism In Males(HIM) study were analyzed. HIM study was a US based cross-sectional study designed to define the prevalence of hypogonadism in men older than 45 years. FT was measured by equilibrium dialysis. Results: Prevalence of subnormal FT concentrations in lean, overweight and obese non-diabetic men was 26%(n=275), 29%(n=687) and 40%(n=489) respectively(p<0.001 for trend); and 44% (n=36), 44%(n=135) and 50%(n=227) respectively in diabetic men (p=0.46 for trend within group, p<0.05 compared to non-diabetic men). Mean FT concentration of diabetic men was significantly lower than that of non-diabetic men. FT concentrations were negatively and significantly (p<0.001) related to age(r=−0.37), BMI(r=−0.18) and SHBG(r=−0.11) in multiple regression analysis. The average decline of FT concentrations was 7.8 pg/ml/decade in non diabetic and 8.4 pg/ml/decade in diabetic men. Conclusion: 40% of obese non-diabetic and 50% of obese diabetic men above the age of 45 years have subnormal FT concentrations. In view of its high prevalence, obesity is probably the condition most frequently associated with subnormal FT concentration in males. The concomitant presence of diabetes is associated with an additional increase in prevalence of subnormal FT concentration.