Fracture Risk High in People With HIV; ART Therapy to Blame?

Norra MacReady

July 26, 2010

July 26, 2010 (Vienna, Austria) — People with HIV have a high risk of developing osteopenia and osteoporosis and should undergo regular bone mineral density screening, speakers reported here at AIDS 2010: XVIII International AIDS Conference.

Anna Bonjoch, MD, PhD, from the University Hospital Germans Trias i Pujol in Barcelona, Spain, and colleagues performed a cross-sectional survey of 671 HIV-infected patients who had undergone at least 1 dual-energy x-ray absorptiometry (DXA) scan to measure bone mineral density. The patients were mostly men and had a median age of 43 years. The vast majority (98%) were on some form of antiretroviral treatment (ART). From their DXA scans, 319 patients (47.5%) were diagnosed with osteopenia, and 155 patients (23%) had frank osteoporosis.

The investigators also conducted a longitudinal analysis on a subgroup of 391 patients, whom they followed-up for a median of 2.5 years, with follow-up time exceeding 5 years for 105 patients. On their first DXA scan, 193 (49%) of those patients had osteopenia. By their last scan, 4 additional patients had joined their ranks.

Osteoporosis was detected on the initial DXA scan in 86 patients (22%). By the final study, osteoporosis was seen in 105 patients (27%). All in all, Dr. Bonjoch said, 12.5% of the patients progressed to osteopenia between their first and final DXA studies, and 15.6% progressed to osteoporosis. The risk factors most strongly associated with osteopenia or osteoporosis in this patient population were male sex, advancing age, low body mass index, and time on protease inhibitors or tenofovir.

In an unrelated, retrospective analysis of 19,398 patients with HIV, 97.5% of whom were men, Roger Bedimo, MD, from the VA North Texas Healthcare System in Dallas, and coauthors found that 200 patients sustained at least 1 osteoporotic fracture of the hip, wrist, or vertebra during a median follow-up period of 3.61 years. Along with advancing age, coinfection with hepatitis C was a risk factor in this study. Hepatitis C was associated with a hazard ratio of 1.33 on univariate analysis (P = .05) and of 1.45 on multivariate analysis (P = .02), although use of highly active ART (HAART) did not increase risk in this population. Black race proved to be a protective factor.

Fracture risk starts much earlier in people with HIV than in the general population, said Patrick W.G. Mallon, MB, PhD, from the School of Medicine and Medical Sciences, Master Misericordiae University Hospital, University College Dublin, Ireland, who cochaired the session at which Dr. Bonjoch presented her findings. In a separate symposium on the adverse effects of HAART, Dr. Mallon cited evidence showing that osteopenia, osteoporosis, and fracture risk are significantly higher in both sexes with HIV at all ages studied compared with the general population. The causes may be multifactorial, but the data suggest that ART must take much of the blame, Dr. Mallon said, especially when the regimen includes protease inhibitors.

Low body mass index is another consistent culprit, although it does not explain the loss of bone mineral density associated with initiation of ART. "To date, there is not a single antiretroviral regimen that has not been associated with bone loss," said Dr. Mallon. He did not participate in Dr. Bonjoch's or Dr. Bedimo's studies.

"Who should be screened? Everybody," Dr. Mallon added. Patients older than 40 years should use the World Health Organization Fracture Risk Assessment Tool, and high-risk individuals — people with a history of low-impact fractures, a risk of falling, postmenopausal women, men older than 50 years, people with hypogonadism, or anyone who has taken steroids — should consider having a DXA scan.

Treatment with bisphosphonates has shown promise in this population, Dr. Mallon said, "but we must be clear on why we're giving these drugs. The reason is to prevent fractures, not to increase bone density."

Dr. Bonjoch and Dr. Bedimo have disclosed no relevant financial relationships. Dr. Mallon has received grants or research support from the Science Foundation Ireland, Molecular Medicine Ireland, the European Union, the Irish Lung Foundation, Mater College, GlaxoSmithKline, and Pfizer. He is on the Speaker's Bureau for or receives honoraria from GlaxoSmithKline, Viiv Healthcare, Merck, Gilead, Abbott, Tibotec, and BMS.

AIDS 2010: XVIII International AIDS Conference: Presentation MOSY0302. Presented July 19, 2010.

AIDS 2010: XVIII International AIDS Conference: Abstract TUAB0104. Presented July 20, 2010.

AIDS 2010: XVIII International AIDS Conference: Abstract THPDB104. Presented July 22, 2010.