Changes in body composition, strength, and endurance that accompany
aging may be related to interactive effects of decreases in growth hormone
and sex steroids. In this 26-week randomized controlled trial, Blackman and
colleagues found that increases in lean body mass were greater among women
and men aged 65 to 88 years who received growth hormone with or without sex
steroid administration than among those who received placebo. In men who received
growth hormone plus testosterone, muscle strength increased slightly and cardiovascular
endurance capacity increased significantly compared with placebo, but women
had no significant change in strength or endurance in any treatment group.
Adverse effects, including diabetes and glucose intolerance, occurred frequently
in study participants who received growth hormone.