Low blood testosterone levels in men over 60 significantly increased their risk of having a bone fracture, according to the authors of a study published in the January 14 issue of the Archives of Internal Medicine. Though the study did not include HIV-positive men, low testosterone levels, also known as hypogonadism, is a condition that frequently affects people living with the virus. Weakened bone density, also known as osteoporosis, is also affecting increasing numbers of people with HIV.

Christian Meier, MD, of the bone research program at the ANZAC Research Institute at the University of Sydney in Australia, and his colleagues examined data collected through the Dubbo Osteoporosis Epidemiology Study, which since 1989 has enrolled all men and women 60 years of age and older living in the Australian city of Dubbo. By 2004 there were 868 men enrolled in the study, of whom 609 had blood samples available from the time of their enrollment and from follow-up visits. The average age of the men was 73 years old.

During the period of observation, 113 men had a low-trauma bone fracture. Nearly 80 percent of the fractures occurred in men who were 70 or older. After accounting for traditional risk factors that can negatively affect bone health, such as age, bone mineral density, calcium intake and history of smoking, having a low testosterone level was independently associated with an increased risk of bone fracture. With every degree that testosterone dropped, the risk of fracture increased significantly.

Though Meier’s team is recommending testosterone replacement therapy only for those with the most severe testosterone deficiencies, they are encouraging other physicians to view low testosterone levels in older men as a potential risk for bone fracture. Though it is not possible to extrapolate the results of this study directly to people living with HIV, particularly men under 60 or HIV-positive women with testosterone deficiency, people who have other risk factors for poor bone health may want to discuss the results of this study with their health care provider.