HIV-positive women taking HAART have less fat in their legs than either HIV-positive women not taking HIV therapy or HIV-negative women, according to a US study published in the January 1st edition of the Journal of Acquired Immune Deficiency Syndromes. The investigators also noted that central fat levels were conserved or fell in women taking HAART, suggesting that HIV-positive women taking antiretroviral therapy may experience body fat changes similar to those seen in HAART-treated HIV-positive men.
Changes in body shape, including peripheral fat loss and central fat gain, as a consequence of HAART have been well described. However, most of the data concerning this side-effect have been gathered from study populations largely composed of men who tended to have a lean body shape before the development of lipodystrophy caused by their antiretroviral therapy.
Many HIV-positive women in the US are, by contrast overweight or obese and the effects of HAART or HIV infection in the context of preexisting obesity has not been well described.
Investigators from the Women’s Interagency HIV Study (WIHS) accordingly performed DEXA scans on183 HIV-positive and 88 HIV-negative at-risk non-pregnant women. The women fasted eight hours before the scan was performed and were weighed and measured to determine body mass index. HIV-positive individuals provided details about their current and past use of antiretroviral therapy, current and nadir CD4 cell count, and current viral load. All the women provided information about their general medical and social histories, exercise patterns, smoking habits and hepatitis B or hepatitis C coinfection.
The HIV-positive and HIV-negative women were broadly comparable, although the HIV-positive women were slightly older (41 versus 37-years).
Body mass index was lower in HIV-positive women (28kg/m2 versus 30kg/m2, p = 0.04), as was weight (73kg versus 78 kg, p = 0.04). However, the differences between HIV-positive and HIV-negative women in weight were entirely explained by differences in fat content. Total fat (p = 0.001), trunk fat (p = 0.01), and leg fat (p = 0.001) were all significantly lower in HIV-positive women than HIV-negative women.
Leg fat was significantly lower in HIV-positive women taking a HAART regimen including a protease inhibitor (p = 0.01), and a HAART regimen without a protease inhibitor (p
In HIV-positive women, the only factor associated with lower trunk and leg fat was exercise of six or more hours per week. Smoking (p = 0.03) and a nadir CD4 cell count below 200 cells/mm3 were associated with lower total and leg fat. Current CD4 cell count was not significantly associated with either total or regional fat. Use of d4T was significantly associated with lower leg fat (p = 0.04).
“This cross-sectional study of fat distribution among women in the WIHS cohort provides evidence of significantly lower levels of leg fat in HIV-infected women on HAART, when compared with both HIV-negative women and HIV-positive women who are not currently using ART”, write the investigators.
They note that earlier reports of body fat changes in women taking HAART have primarily focused on central fat accumulation. “The results of the present study are more comparable to those described…in a cross-sectional study in a group of subjects who were predominately male, white, and lean”, add the investigators.
Mulligans K et al. Fat distribution in HIV-infected women in the United States: DEXA substudy in the Women’s Interagency HIV Study. J Acquir Immune Defic Syndr 38: 18 – 22, 2004.