ROME – Exposure to tenofovir and other antiretroviral agents over time is not independently associated with an increased risk of bone fracture in aging men living with HIV, investigators reported.
Complications of HIV and antiretroviral treatment are particularly important to identify – and separate from traditional risk factors – in aging HIV-positive populations. Several presenters at the International AIDS Society Conference on HIV Pathogenesis and Treatment focused on complications of long-term infection and exposure to treatment agents. The antiretroviral drug tenofovir, for example, is known to be associated with decreased bone mineral density.
Dr. Roger Bedimo of the VA North Texas Health Care System and the University of Texas Southwestern Medical Center in Dallas told the conference that his group’s retrospective cohort study looked at 56,660 people with HIV (mean age, 45), 98% of whom were male. Patients received different antiretroviral regimens between 1988 and 2009.
Antiretroviral therapy (ART) with tenofovir and ART with boosted protease inhibitors were regimens found to be associated with a modest increased risk of osteoporotic fracture after a median 4.5 years of follow-up – but this risk was no longer significant when the investigators controlled for the traditional risk factors of race, body mass index, age, tobacco use, and diabetes.
Though an increased risk of fracture was seen in the cohort as a whole after the introduction of highly active antiretroviral therapy in 1996, this was believed to be attributable to aging and longer survival of subjects. Bone mineral density was not measured in the study.
Separately, Italian researchers, led by Dr. Giovanni Guaraldi of the University of Modena, presented findings from a smaller study designed to test interactions between bone density and elevated coronary artery calcium – a known risk factor for cardiovascular disease – in a group of 681 HIV-infected patients. They found elevated coronary artery calcium to be significantly associated with low femoral bone mineral density (OR, 2.24) but not low lumbar bone mineral density.
Dr. Guaraldi said that further studies were needed to determine "how heart and bone disease talk to each other" in aging HIV-positive populations, and that he felt that nondrug interventions might be able to simultaneously mediate bone-density and cardiovascular risks in this patient group. "Lifestyle is a key component of the risk of both cardiovascular risk and fracture," Dr. Guaraldi said. "Properly designed studies to improve lifestyle may help these patients to reduce cardiovascular and bone disease."
The investigators did not report whether they had any relevant financial disclosures.