Altered fat distribution in HIV-positive men on nucleoside analog reverse transcriptase inhibitor therapy

To determine whether HIV infection, the wasting syndrome, or nucleoside ana log reverse transcriptase inhibitor (NRTI) or protease inhibitor (PI) thera py uniquely affect fat distribution in men, we performed manual regional an alysis of total, appendicular, trunk, and central abdominal fat measured by dual-energy X-ray absorptiometry (DEXA). Five groups of study subjects wer e identified for this cross-sectional analysis: HIV-negative controls (HIV- : N = 44) and four groups of HIV-positive subjects: antiretroviral (ARV)-na ive or with limited prior use of NRTIs (ARV-; N = 23): on NRTIs for greater than or equal to6 months but PI-naive (NRTI; N = 30), on an NRTI/PI regime n for greater than or equal to6 months but with no complaints of abnormal f at distribution (NRTI/PI; N = 26): and those on NRTIs but PI-naive with the wasting syndrome (NRTI/WS, N = 40). Total, appendicular, trunk, and centra l abdominal fat was significantly lower in NRTI/WS. The ratio of trunk fat to appendicular fat was virtually identical in HIV- and ARV-. This ratio wa s significantly higher in the NRTI, NRTI/PI, and NRTI/WS groups, and values in these three groups were similar. These cross-sectional data suggest tha t HIV-infected men receiving NRTIs have an altered pattern of fat distribut ion, compared with HIV-negative men and HIV-positive men who are not receiv ing antiretroviral therapy. This effect was independent of the concomitant use of a PI or a diagnosis of the wasting syndrome. We saw no evidence of a unique effect of HIV infection per se on regional fat distribution. Althou gh the fat ratio is increasingly employed, its physiologic significance is unclear. Our results, which have been obtained retrospectively, are intende d to provide the impetus for prospective. controlled studies of the interac tions among drug and host factors in the development of fat distribution ab normalities.