Low serum testosterone and mortality in older men.
BACKGROUND
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
The objective of the study was to examine the association of endogenous testosterone levels with mortality in older community-dwelling men.


METHODS
This was a prospective, population-based study of 794 men, aged 50-91 (median 73.6) yr who had serum testosterone measurements at baseline (1984-1987) and were followed for mortality through July 2004.


METHODS
All-cause mortality by serum testosterone level was measured.


RESULTS
During an average 11.8-yr follow-up, 538 deaths occurred. Men whose total testosterone levels were in the lowest quartile (<241 ng/dl) were 40% [hazards ratio (HR) 1.40; 95% confidence interval (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 C-reactive protein. 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 yr, independent of multiple risk factors and several preexisting health conditions.
Laughlin
Gail A
GA
Department of Family and Preventive Medicine, School of Medicine, University of California, San Diego, 9500 Gilman Drive, MC 0631C, La Jolla, California 92093, USA. glaughlin@ucsd.edu
Barrett-Connor
Elizabeth
E
Bergstrom
Jaclyn
J
D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002140:California; D002318:Cardiovascular Diseases / Q000097:blood / Q000401:mortality*; D008076:Cholesterol, HDL / Q000097:blood; D015331:Cohort Studies; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood / Q000401:mortality*; D011446:Prospective Studies; D012140:Respiratory Tract Diseases / Q000401:mortality*; D018709:Statistics, Nonparametric; D013739:Testosterone / Q000097:blood*; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D008076:Cholesterol, HDL; D015850:Interleukin-6; D014280:Triglycerides; D013739:Testosterone; D002097:C-Reactive Protein