Conclusions The effects of testosterone on cardiovascular-related events varied with source of funding .
Nevertheless , overall and particularly in trials not funded by the pharmaceutical industry , exogenous testosterone increased the risk of cardiovascular-related events , with corresponding implication s for the use of testosterone therapy
Background Testosterone therapy is increasingly promoted .
No r and omized placebo-controlled trial has been implemented to assess the effect of testosterone therapy on cardiovascular events , although very high levels of and rogens are thought to promote cardiovascular disease .
Effect of testosterone treatment on body composition and muscle strength in men over 65 years of age.
As men age , serum testosterone concentrations decrease , the percentage of body mass that is fat increases , the percentage of lean body mass decreases , and muscle strength decreases . Because these changes are similar to those that occur in hypogonadal men , we hypothesized that increasing the serum testosterone concentration of men over 65 yr of age to that in young men would decrease their fat mass , increase their lean mass , and increase their muscle strength . We r and omized 108 men over 65 yr of age to wear either a testosterone patch or a placebo patch in a double blind study for 36 months . We measured body composition by dual energy x-ray absorptiometry and muscle strength by dynamometer before and during treatment . Ninety-six men completed the entire 36-month protocol .  Fat mass decreased ( -3.0+/-0.5 kg ) in the testosterone-treated men during the 36 months of treatment , which was significantly different ( P = 0.001 ) from the decrease ( -0.7+/-0.5 kg ) in the placebo-treated men . Lean mass increased ( 1.9+/-0.3 kg ) in the testosterone-treated men , which was significantly different ( P < 0.001 ) from that ( 0.2+/-0.2 kg ) in the placebo-treated men . The decrease in fat mass in the testosterone-treated men was principally in the arms ( -0.7+/-0.1 kg ; P < 0.001 compared to the placebo group ) and legs ( -1.1+/-0.2 kg ; P < 0.001 ) , and the increase in lean mass was principally in the trunk ( 1.9+/-0.3 kg ; P < 0.001 ) . The change in strength of knee extension and flexion at 60 degrees and 180 degrees angular velocity during treatment , however , was not significantly different between the two groups . We conclude that increasing the serum testosterone concentrations of normal men over 65 yr of age to the midnormal range for young men decreased fat mass , principally in the arms and legs , and increased lean mass , principally in the trunk , but did not increase the strength of knee extension and flexion , as measured by dynamometer
Conclusions The effects of testosterone on cardiovascular-related events varied with source of funding .
Nevertheless , overall and particularly in trials not funded by the pharmaceutical industry , exogenous testosterone increased the risk of cardiovascular-related events , with corresponding implication s for the use of testosterone therapy
Background Testosterone therapy is increasingly promoted .
No r and omized placebo-controlled trial has been implemented to assess the effect of testosterone therapy on cardiovascular events , although very high levels of and rogens are thought to promote cardiovascular disease .