Conclusions Oral TRT produces significant CV risk .
Differences in the degree to which serum DHT is elevated may underlie the varying CV risk by TRT administration route , as elevated serum dihydrotestosterone has been shown to be associated with CV risk in observational studies
Background Potential cardiovascular ( CV ) risks of testosterone replacement therapy ( TRT ) are currently a topic of intense interest .
However , no studies have addressed CV risk as a function of the route of administration of TRT .
Dutasteride reduces prostate size and prostate specific antigen in older hypogonadal men with benign prostatic hyperplasia undergoing testosterone replacement therapy.
PURPOSE Benign prostatic hyperplasia and hypogonadism are common disorders in aging men . There is concern that and rogen replacement in older men may increase prostate size and symptoms of benign prostatic hyperplasia . We examined whether combining dutasteride , which inhibits testosterone to dihydrotestosterone conversion , with testosterone treatment in older hypogonadal men with benign prostatic hyperplasia reduces and rogenic stimulation of the prostate compared to testosterone alone . MATERIAL S AND METHODS We conducted a double-blind , placebo controlled trial of 53 men 51 to 82 years old with symptomatic benign prostatic hyperplasia , prostate volume 30 cc or greater and serum total testosterone less than 280 ng/dl ( less than 9.7 nmol/l ) . Subjects were r and omized to daily transdermal 1 % T gel plus oral placebo or dutasteride for 6 months . Testosterone dosing was adjusted to a serum testosterone of 500 to 1,000 ng/dl . The primary outcomes were prostate volume measured by magnetic resonance imaging , serum prostate specific antigen and and rogen levels . RESULTS A total of 46 subjects completed all procedures . Serum testosterone increased similarly into the mid-normal range in both groups . Serum dihydrotestosterone increased in the testosterone only but decreased in the testosterone plus dutasteride group . In the testosterone plus dutasteride  group prostate volume and prostate specific antigen ( mean ± SEM ) decreased 12 % ± 2.5 % and 35 % ± 5 % , respectively , compared to the testosterone only group in which prostate volume and prostate specific antigen increased 7.5 % ± 3.3 % and 19 % ± 7 % ( p = 0.03 and p = 0.008 ) , respectively , after 6 months of treatment . Prostate symptom scores improved in both groups . CONCLUSIONS Combined treatment with testosterone plus dutasteride reduces prostate volume and prostate specific antigen compared to testosterone only . Coadministration of a 5α-reductase inhibitor with testosterone appears to spare the prostate from and rogenic stimulation during testosterone replacement in older , hypogonadal men with symptomatic benign prostatic hyperplasia
Conclusions Oral TRT produces significant CV risk .
Differences in the degree to which serum DHT is elevated may underlie the varying CV risk by TRT administration route , as elevated serum dihydrotestosterone has been shown to be associated with CV risk in observational studies
Background Potential cardiovascular ( CV ) risks of testosterone replacement therapy ( TRT ) are currently a topic of intense interest .
However , no studies have addressed CV risk as a function of the route of administration of TRT .