Optimal testosterone levels are a biomarker for better survival in older men, according to a new study.
The study of 3,690 community-dwelling men aged 70-89 years showed that those with midrange levels of testosterone and dihydrotestosterone (DHT) had the lowest all-cause mortality and those with higher DHT had lower mortality from ischemic heart disease (IHD). Estradiol levels did not predict all-cause or IHD mortality.
Of the 3,690 men, 974 (26.4%) died, including 325 who died from IHD. Men who died had significantly lower mean baseline total testosterone levels (12.8 vs. 13.2 nmol/L), DHT levels (1.4 vs. 1.5 nmol/L), and estradiol (71.6 vs. 74.0 pmol/L), Bu Beng Yeap, MBBS, PhD, of Fremantle Hospital in Fremantle, Western Australia, and colleagues reported online ahead of print in The Journal of Clinical Endocrinology & Metabolism.
After controlling for other risk factors, men in the second and third quartiles of total testosterone had a significant 18% and 22% decreased risk of death from any cause, respectively, compared with those in the first quartile. Men in the third quartile of DHT had a significant 24% decreased risk of death from any cause compared with men in the first quartile. Death risk was not significantly lower among men in the fourth quartile of total testosterone or DHT compared with the first quartile.
Additionally, results showed that men in the third or fourth quartiles of DHT had a significant 42% and 31% decreased risk of death from IHD, respectively, compared with men in the first quartile.