Low Testosterone Levels Linked to Increased Mortality

But researchers stress there's no evidence that boosting levels will reduce risk.

By Jeffrey Perkel
HealthDay Reporter
Wednesday, June 6, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

TUESDAY, June 5 (HealthDay News) -- Men 50 and older with low levels of testosterone may be at higher risk of dying within 20 years than men with higher levels of the male hormone, a new study suggests.

But, the researchers stressed, more studies are need to examine the potential link, and there's nothing to indicate that testosterone supplements would reduce the risk of death.

For the study, Gail Laughlin, an assistant professor of family and preventative medicine at the University of California, San Diego, and colleagues followed almost 800 men, aged 50 to 91, for 18 years as part of the "Rancho Bernardo Study," looking at the relationship between serum testosterone levels and mortality.

They found that men with low testosterone had a 33 percent higher risk of dying from any cause than men with either normal or elevated testosterone levels. This link stood up regardless of age, physical activity, or lifestyle -- including smoking and drinking. But the link grew weaker when adjusted for metabolic syndrome and inflammatory biomarkers such as interleukin-6 and C-reactive protein, Laughlin said.

Metabolic syndrome is a condition defined by a constellation of risk factors for cardiovascular disease, such as high blood pressure, high blood glucose, and a waist diameter greater than 40 inches in men.

The study authors concluded that the relationship between low testosterone levels and mortality "is explained in part by the metabolic syndrome, and is dependent on the association of low testosterone levels with elevated markers of inflammation."

The findings were to be presented Tuesday at the Endocrine Society's annual meeting, in Toronto.

Dr. Glenn Braunstein, chairman of medicine at Cedars-Sinai Medical Center in Los Angeles, called the study "very interesting." But he noted that drawing conclusions from a single testosterone reading can be misleading, because the hormone's levels fluctuate throughout the day. "So taking a single testosterone level and extrapolating from that is not the be-all and end-all," he said.