The present analysis provides an estimate of the average treatment effects of testosterone therapy in middle-aged men .
OBJECTIVES Ageing in men is associated with a gradual decline in serum testosterone levels and a concomitant loss of muscle mass , accumulation of central adiposity , impaired mobility and increased risk of bone fractures .
Whether and rogen treatment might be beneficial in these subjects is still under debate .
We have carried out a systematic review of r and omized controlled trials ( RCTs ) evaluating the effects of testosterone ( T ) administration  to middle-aged and ageing men on body composition , muscle strength , bone density , markers of bone metabolism and serum lipid profile .
Longitudinal relation between endogenous testosterone and cardiovascular disease risk factors in middle-aged men. A 13-year follow-up of former Multiple Risk Factor Intervention Trial participants.
The present study examined lifestyle and behavioral correlates of the change in total testosterone over 13 years in 66 men aged 41 - 61 years who were former participants of the Multiple Risk Factor Intervention Trial ( MRFIT ) at the Pittsburgh , Pennsylvania , center . The authors also determined in these men if changes in total testosterone are related to changes in cardiovascular disease risk factors . The mean total testosterone level was 751 ( st and ard deviation , 248 ) ng/dl at baseline and decreased by 41 ( st and ard deviation , 314 ) ng/dl during follow-up . The correlation between measures was r = 0.44 ( p < 0.001 ) . In multivariate analysis , higher type A coronary-prone behavior score , greater pack-years of cigarette smoking , and the MRFIT special intervention group were associated with larger decreases in total testosterone . Age , body weight , weight change , leisure time activity level , and alcohol intake were not related to the change in total testosterone . The decrease in endogenous testosterone was associated with an increase in triglycerides and a decrease in high density lipoprotein cholesterol in multivariate analysis controlling for obesity and other lifestyle covariates . There was little relation between change in testosterone and change in total and low density lipoprotein cholesterol or blood pressure . This longitudinal study confirms a gradual decline in total testosterone levels with advancing age in older men and provides evidence that lifestyle and psychosocial factors are related to this decline . Decreases in endogenous testosterone levels with age in men are associated with potentially unfavorable changes in triglycerides and high density lipoprotein cholesterol
The present analysis provides an estimate of the average treatment effects of testosterone therapy in middle-aged men .
OBJECTIVES Ageing in men is associated with a gradual decline in serum testosterone levels and a concomitant loss of muscle mass , accumulation of central adiposity , impaired mobility and increased risk of bone fractures .
Whether and rogen treatment might be beneficial in these subjects is still under debate .
We have carried out a systematic review of r and omized controlled trials ( RCTs ) evaluating the effects of testosterone ( T ) administration  to middle-aged and ageing men on body composition , muscle strength , bone density , markers of bone metabolism and serum lipid profile .