Effect of Different Antiretroviral Drug Regimens on Body Fat Distribution of HIV-Infected South African Women

Abstract

No African studies have examined the effect of first-line nonnucleoside reverse transcriptase inhibitor (NNRTI)-based and second-line protease inhibitor (PI)-based antiretroviral therapy (ART) on body composition. We compared body composition in HIV-infected black South African women receiving NNRTI-based ART (ART1, n=344), PI-based ART (ART2, n=91), and those not on ART (ART-naive, n=309). Accordingly, body composition was measured using dual energy x-ray absorptiometry (DXA) and anthropometry in a cross-sectional study. Despite similar body mass index (BMI), ART1 and ART2 had greater central fat mass (FM) [median (IQR): 44.2 (39.4-50.1) and 46.9 (39.3-52.8) vs. 41.1 (36.3-45.2) %FM, p<0.01] and less leg FM [41.2 (34.8-45.8) and 40.2 (32.9-45.7) vs. 43.9 (39.3-48.1) %FM, p<0.01] than ART-naive women. Within ART1, waist:hip was greater [0.87 (0.81-0.92) vs. 0.84 (0.78-0.89), p=0.006], while calf skinfold was lower [15.2 (9.4-21.5) vs. 17.4 (12.0-23.6) mm, p=0.033] in women receiving efavirenz compared to nevirapine. ART2 had a greater waist:hip, and abdominal, subscapular, and suprailiac skinfolds than ART1 (p<0.05). After adjusting for time on d4T (stavudine), ART2 had greater body fat than ART1 (p<0.05). With increasing time on d4T, the decrease in leg fat (%FM) was higher in ART1 than ART2 (p=0.012, for time×treatment effect). A similar interaction was reported for total time on ART treatment (p=0.002 for time×treatment effect). In conclusion, ART was associated with increased central fat and reduced peripheral fat. Changing to a PI-based regimen in ART2, which also substitutes stavudine with zidovudine, partially reversed the peripheral fat loss observed on ART1.