Context: Declining testosterone levels in elderly men are thought to underlie many of the symptoms and diseases of aging, however studies demonstrating associations of low testosterone with clinical outcomes are few.

Objective: To examine the association of endogenous testosterone levels with mortality in older community-dwelling men.

Design, Setting, and Participants: Prospective population-based study of 794 men, aged 50 to 91 (median 73.6) years who had serum testosterone measurements at baseline (1984–87) and were followed for mortality through July, 2004.

Main Outcome Measure: All cause mortality by serum testosterone level.

Results: During an average 11.8 year follow-up, 538 deaths occurred. Men whose total testosterone levels were in the lowest quartile (<241 ng/dl) were 40% (HR=1.40; 95% CI, 1.14–1.71) more likely to die than those with higher levels, independent of age, adiposity and lifestyle. Additional adjustment for health status markers, lipids, lipoproteins, blood pressure, glycemia, adipocytokines and estradiol levels had minimal effect on results. The low testosterone-mortality association was also independent of the metabolic syndrome, diabetes and prevalent cardiovascular disease, but was attenuated by adjustment for IL-6 and CRP. In cause-specific analyses, low testosterone predicted increased risk of cardiovascular (HR, 1.38; 95% CI, 1.02- 1.85) and respiratory disease (HR, 2.29; 95% CI, 1.25–4.20) mortality, but was not significantly related to cancer death (HR, 1.34; 95% CI, 0.89, 2.00). Results were similar for bioavailable testosterone.

Conclusions: Testosterone insufficiency in older men is associated with increased risk of death over the following 20 years, independent of multiple risk factors and several pre-existing health conditions.