Age of study population and year of publication modified the relationship between testosterone and CVD .
Results were largely confirmed by separate analyses of free- and bioavailable testosterone .
The systematic review displayed no association between endogenous testosterone and risk for CVD in middle-aged men .
In elderly men , testosterone may weakly protect against CVD .
Alternatively , low testosterone may indicate a poor general health
CONTEXT The literature provides no clear answer as to whether low endogenous testosterone increases risk of cardiovascular disease ( CVD ) in healthy men .
OBJECTIVE Our purpose was to estimate the predictive value of testosterone for CVD and to identify study features explaining conflicting results .
Low serum testosterone and estradiol predict mortality in elderly men.
CONTEXT Age-related reduction of serum testosterone may contribute to the signs and symptoms of aging , but previous studies report conflicting evidence about testosterone levels and male mortality . No large prospect i ve cohort study has determined a possible association between serum estradiol and mortality in men . OBJECTIVE The main objective was to examine the association between serum testosterone and estradiol and all-cause mortality  in elderly men . DESIGN , SETTING , AND PARTICIPANTS We used specific gas chromatography-mass spectrometry to analyze serum sex steroids at baseline in older men who participated in the prospect i ve population -based MrOS Sweden cohort ( n = 3014 ; mean age , 75 yr ; range , 69 - 80 yr ) . MAIN OUTCOME MEASURE All-cause mortality by serum testosterone and estradiol levels . RESULTS During a mean follow-up period of 4.5 yr , 383 deaths occurred . In multivariate hazards regression models , low levels ( within quartile 1 vs. quartiles 2 - 4 ) of both testosterone [ hazard ratio ( HR ) , 1.65 ; 95 % confidence interval ( CI ) , 1.29 - 2.12 ] and estradiol ( HR , 1.54 ; 95 % CI , 1.22 - 1.95 ) associated with mortality . A model including both hormones showed that both low testosterone ( HR , 1.46 ; 95 % CI , 1.11 - 1.92 ) and estradiol ( HR , 1.33 ; 95 % CI , 1.02 - 1.73 ) predicted mortality . Risk of death nearly doubled ( HR , 1.96 ; 95 % CI , 1.46 - 2.62 ) in subjects with low levels of both testosterone and estradiol compared with subjects within quartiles 2 - 4 of both hormones . CONCLUSIONS Elderly men with low serum testosterone and estradiol have increased risk of mortality , and subjects with low values of both testosterone and estradiol have the highest risk of mortality
Age of study population and year of publication modified the relationship between testosterone and CVD .
Results were largely confirmed by separate analyses of free- and bioavailable testosterone .
The systematic review displayed no association between endogenous testosterone and risk for CVD in middle-aged men .
In elderly men , testosterone may weakly protect against CVD .
Alternatively , low testosterone may indicate a poor general health
CONTEXT The literature provides no clear answer as to whether low endogenous testosterone increases risk of cardiovascular disease ( CVD ) in healthy men .
OBJECTIVE Our purpose was to estimate the predictive value of testosterone for CVD and to identify study features explaining conflicting results .