Effects of androgen therapy on adipose tissue and metabolism in older men.

We investigated the effects of oxandrolone on regional fat compartments and markers of metabolism. Thirty-two 60- to 87-yr-old men (body mass index, 28.1 +/- 3.4 kg/m(2)) were randomized to oxandrolone (20 mg/d; n = 20) or matching placebo (n = 12) treatment for 12 wk. Oxandrolone reduced total (-1.8 +/- 1.0 kg; P < 0.001), trunk (-1.2 +/- 0.6 kg; P < 0.001), and appendicular (-0.6 +/- 0.6 kg; P < 0.001) fat, as determined by dual energy x-ray absorptiometry. The changes in total and trunk fat were greater (P < 0.001) than the changes with placebo. By magnetic resonance imaging, visceral adipose tissue decreased (-20.9 +/- 12 cm(2); P < 0.001), abdominal sc adipose tissue (SAT) declined (-10.7 +/- 12.1 cm(2); P = 0.043), the ratio VAT/SAT declined from 0.57 +/- 0.23 to 0.49 +/- 0.19 (P = 0.002), and proximal and distal thigh SC fat declined [-8.3 +/- 6.7 cm(2) (P < 0.001) and -2.2 +/- 3.0 kg (P = 0.004), respectively]. Changes in proximal and distal thigh SC fat with oxandrolone were different than with placebo (P = 0.018 and P = 0.059). A marker of insulin sensitivity (quantitative insulin sensitivity check index) improved with oxandrolone by 0.0041 +/- 0.0071 (P = 0.018) at study wk 12. Changes in total fat, abdominal SAT, and proximal extremity SC fat were correlated with changes in fasting insulin from baseline to study wk 12 (r >or= 0.45; P < 0.05). Losses of total fat and SAT were greater in men with baseline testosterone of 10.4 nmol/liter or less (