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Background:  While morphologic abnormalities are common among HIV-infected men who have sex with men receiving highly active antiretroviral therapy (HAART), it is not clear how body shape changes over time in HAART-treated, HIV-positive MSM compared to HIV-negative men who have sex with men of similar age.

Methods:  Since September 1999, men enrolled in the Multicenter AIDS Cohort Study underwent circumference measurements of the waist, hip, thigh, and arm at each semi-annual visit. Changes in anthropometric measurements occurring between 1999 and 2003 among HIV-positive men receiving HAART were compared to HIV-negative men using mixed-model regression methods. Analyses were adjusted for age, nadir CD4 cell count, and body mass index (for circumference measurements). In addition, the effect of cumulative exposure to each of the three major antiretroviral classes on anthropometric changes was assessed. 

Results:  At the baseline visit, HIV⁺/HAART-treated men (n = 488) had lower mean body mass index, and smaller waist, hip, arm, and thigh circumferences compared to HIV-negative men (n = 392). Over the 4-year observation period, mean body mass index increased significantly among HIV-negative men (0.12 kg/m²/year, p < 0.001), but did not change in the HIV⁺/HAART-treated group (–0.006 kg/m²/year, p = ns; p = 0.008 for comparison between groups). Mean waist circumference increased similarly in both HIV-negative group and HIV⁺/HAART-treated group (0.55 cm/year vs 0.65 cm/year, p = ns), but hip circumference increased more slowly in the HIV⁺/HAART-treated group than in the HIV-negative group (0.18 vs 0.49 cm/year, p < 0.001), yielding a significant increase in the waist-to-hip ratio in the HIV⁺/HAART-treated group over time (0.005/year, p < 0.001). Mean annual change in thigh circumference differed between the groups (0.54 cm/year vs –0.14 cm/year, p = 0.033), with a significant increase observed in the HIV-negative group, but no mean change in the HIV⁺/HAART-treated group. Cumulative exposure to nucleoside reverse transcriptase inhibitors (NRTI) was significantly associated with decreasing waist, hip, arm, and thigh circumferences, as well as increasing waist-to-hip ratio and decreasing body mass index, independent of PI use.

Conclusions:  Over the 4-year interval, HIV⁺ men who have sex with men with HAART exposure showed significant differences in the annual change of waist-to-hip ratio and hip and thigh circumference compared to the HIV-negative men, independent of differences in body mass index. These changes were related to cumulative NRTI exposure.

Keywords: anthropometric; waist:hip ratio; thigh circumference