Over 50% of HIV-positive individuals had bone problems in an Italian study published in the December 1st edition of the Journal of Acquired Immune Deficiency Syndromes. The investigators from Milan found that a high viral load and duration of anti-HIV treatment were associated with osteopenia – decreased bone density, and/or osteoporosis – decreased bone mass.
Several possible explanations have been offered for the increased frequency of bone problems seen in HIV-positive individuals including the use of certain anti-HIV drugs, lipodystrophy, immune reconstitution, and factors related to HIV infection itself. Doctors from Milan designed a study to see if duration of anti-HIV therapy and HIV infection were related to osteopenia and/or osteopororis.
The study involved 179 HIV-positive individuals aged between 30 and 50 years. The investigators excluded individuals with any recognised risk factor for bone problems. Most patients (63%) were male, 57% were gay or bisexual men, 16% had been diagnosed with AIDS, 34% were coinfected with hepatitis C virus and 30% had lipodystrophy.
Individuals had been infected with HIV for a median of 102 months and the median duration of potent antiretroviral therapy was 41 months.
DEXA scans indicated that 54% of individuals had problems with their bones, including 43% who had osteopenia and 11% who had osteoporosis.
Factors found to be independently associated with osteopenia or osteoporosis were older age (11% increase in risk for each additional year of age, p < 0.01), low body mass index (p < 0.01), high HIV viral load (each additional log10 increase, p < 0.01) and length of duration of antiretroviral therapy (odds ratio 2.9 for patients who had taken five or more years of therapy versus patients who had taken less than a year of HIV treatment).
“Osteopenia and osteoporosis are frequent findings in HIV-infected subjects”, write the investigators. Although they note that traditional risk factors for bone problems were found to be important in their study, they emphasise “the correlation between higher HIV RNA levels and osteopenia and/or osteoporosis suggest a direct role of HIV on bone turnover cells.” In addition, “the correlation between HAART duration of over a year and osteopenia and/or osteoporosis suggests a role for antiretroviral treatment.”
The investigators did not gather data on individual anti-HIV drugs that were used and were therefore unable to comment on the role of particular drugs or drug classes in the development of bone problems.
Bongiovanni M et al. Osteoporosis in HIV-infected subjects: combined effect of highly active antiretroviral therapy and HIV itself? J Acquir Immune Defic Syndr 40: 503 – 504, 2005.