Testosterone replacement therapy significantly reduced fasting glucose levels and insulin resistance and reversed endothelial dysfunction in men with comorbid obesity, hypogonadism, and type 2 diabetes, according to a study published in The Aging Male.
The study population included 55 male patients with obesity between ages 40–70 with type 2 diabetes from the Diabetic Outpatient Clinic of the General Hospital Celje in Celje, Slovenia.
The sample also presented late-onset hypogonadism and was not being treated with insulin. Participants were randomly assigned into a placebo group and a testosterone group, receiving injections (placebo or testosterone respectively) at first visit, 6 weeks, and then every 10 weeks until the end of study. Examinations were performed and measurements and blood samples taken at baseline and after 12 months.
After 1 year of treatment, the testosterone group demonstrated decreased fasting plasma glucose, but no change was observed in the placebo group. In addition, insulin resistance and plasma insulin levels were significantly reduced in the testosterone group. Flow-mediated dilation rates were significantly improved and intima media thickness was reduced in the testosterone group (a small decrease was also observed in the placebo group, but only half of what the testosterone group experienced).
No significant change in blood pressure levels, triglycerides, or low- or high-density lipoprotein cholesterol was reported by either group. Results showed a significant positive correlation between testosterone replacement therapy and vascular function and demonstrated the positive role of testosterone on glycemic control and insulin sensitivity.
As expected, testosterone levels increased in the testosterone group — pushing those individuals into eugonadal range — and body mass index and waist circumference were reduced in both groups, which the authors suggest indicates a “general positive effect of participating in the study.”
Clinicians treating men with comorbid obesity, type 2 diabetes, and confirmed hypogonadism should consider testosterone replacement therapy as a first-line approach because it “improved glycemic control and endothelial function while exerting no ill effects on the study population.”
Groti K, Žuran I, Antonič B, Foršnarič L, Pfeifer M. The impact of testosterone replacement therapy on glycemic control, vascular function, and components of the metabolic syndrome in obese hypogonadal men with type 2 diabetes [published online April 30, 2018]. Aging Male. doi: 10.1081/13685538.2018.1468429