| Abstract | Background: It is generally accepted that testosterone therapy increases lean body mass (LBM) and decreases total fat mass (TFM) in ageing men. The major challenge is, however, to determine if ageing men would metabolically benefit from testosterone therapy. We have previously reported that six months testosterone therapy did not change insulin sensitivity. Changes in regional body fat distribution and in the levels of the insulin sensitizing adipokine adiponectin may, however, have opposite directed effects on i.e. insulin sensitivity.
Aim: We investigated the effect of testosterone therapy on regional body fat distribution measured by DXA and MRI and adiponectin levels in ageing men with low normal bioavailable testosterone levels.
Methods: A randomized, double-blinded, placebo-controlled study of six months testosterone treatment (gel) in 38 men, aged 60-78 years, with bioavailable testosterone < 7.3 nmol/l and a waist circumference > 94 cm. Central fat mass (CFM) and lower extremity fat mass (LEFM) were measured by DXA. Subcutaneous abdominal adipose tissue (SAT), visceral adipose tissue (VAT) and thigh subcutaneous fat area (TFA) were measured by magnetic resonance imaging (MRI). Coefficients (b) represent the placebo-controlled mean effect of intervention.
Results: Testosterone treatment decreased SAT (b= -0.03 fat area/total area, p= 0.018) and TFA (b= -0.03 area/total area, p<0.001) while VAT (b= 0.01 area/total area; p=0.54) remained unchanged. Adiponectin levels decreased during testosterone therapy (b=-1.308 mg/l, p=0.001).
Conclusion: Our data showed a positive effect on abdominal fat (SAT), however, adiponectin levels were significantly decreased during testosterone therapy. |