Correlation between serum total testosterone levels and type 2 diabetes in elderly patients / 中华老年医学杂志

ABSTRACT

Objective To investigate the association between serum total testosterone (TT ) levels and type 2 diabetes(T2DM )and any gender differences in elderly patients. Methods Based on the Aging Health database built from 2008 to 2012 ,935 elderly individuals over 60 years old with a mean age of 65.8 years receiving physical examinations were included.According to the 1999 WHO criteria for diabetes ,participants were assigned into four groupsa T2DM group(n＝298) ,an impaired fasting glucose(IFG)group(n＝26) ,an impaired glucose tolerance(IGT)group(n＝121) ,and a normal glucose regulation(NGR)group(n ＝ 490).We measured serum TT by ELISA and analyzed the distribution patterns in the groups.Furthermore ,we examined the gender-specific correlation of TT with T2DM and homeostasis model assessment of insulin resistance (HOMA-IR). Results The prevalence of T2DM in the participants was 31.9%(298/935).One-way ANOVA analysis showed that the TT level was higher in the NGR group than in the T2DM and IGT groups (PANOVA＝ 0.001) . Logistic regression analysis indicated a significant protective association between TT and T 2DM in the elderly.Every one unit of increase in the SD of the TT level was accompanied by a 23% reduction in the risk for T2DM (P＝ 0.001).Further gender-stratification analysis suggested that the protective role of TT against T2DM only existed in males (OR＝ 0.55 ,95% CI0.44-0.68 ;P＜ 0.001).After adjustment for age ,blood pressure ,blood lipids ,and waist circumference ,the protective role of TT against T2DM in males still remained (OR ＝ 0.68 ,95% CI0.53-0.86 ;P ＝ 0.002 ).Pearson correlation analysis also indicated a significant negative correlation between TT and HOMA-IR in older males(P＝0.002).As for older females ,no significant correlation of TT with T2DM and HOMA-IR was found. Conclusions The serum TT level might be an independent protective factor for T 2DM in older males ,as evidenced by its correlation with improved insulin resistance status ,which is not present in older females.