Lipodystrophy associated with lower CD4+ T cell counts

Lipodystrophy is one of the most distressing problems many HIV-infected patients confront. Unfortunately, despite intensive research in the past 6 years, the exact mechanism and aetiology of lipodystrophy have yet to be settled upon.

Still, there has been no shortage of theories in this regard, many of which have been proved to be either partially or fully erroneous. One thing that is clear at this point is that lipodystrophy is likely to be multifactorial in origin, with host, disease, and treatment factors all having some role. Further, it may be that the two aspects of lipodystrophy, peripheral fat loss (lipoatrophy) and central fat gain, have different causes or patient-specific predisposing factors.

In a study presented at the 9th Conference on Retroviruses and Opportunistic Infections, Lichtenstein and colleagues involved in the HOPS study evaluated the potential causes of lipoatrophy. This study involved a prospective cohort analysis of 337 HIV-1-infected patients who had no evidence of lipoatrophy at the start of the study and either did or did not develop lipoatrophy over the ensuing 21 months.

The diagnosis of lipoatrophy in this study was based upon a standardised interview and physician assessment and the incidence of fat loss in the extremities, hips or buttocks and sunken cheeks – without total body weight loss – was analysed in stratified and multivariate analyses for their relationship to immunologic, virologic, clinical and drug treatment data for each patient.

Of the 337 patients, 44 (13.1%) developed lipoatrophy during the follow-up period. Using multivariate analysis, the significant risk factors for developing lipoatrophy were white race (OR 5.17), CD4+ T cell count at the follow-up survey of less than 100 cells/mm3 (OR 4.15), and body mass index less than 24 kg/m2 (OR 2.43). Notably, there was no association found between lipoatrophy and duration of use, initiation, continuation, or discontinuation of any antiretroviral medication.

The most significant factor found to be associated with lipoatrophy in this study was the patients CD4+ T cell count, and patients who consistently had a CD4+ T cell count >350 cells/mm3 had a very low rate of lipoatrophy (3.3%) whereas patients with a CD4+ T cell count consistently <200 cells/mm3 had a relatively high rate of lipoatrophy (30.8%).

The authors conclude, “Factors associated with severity of HIV-1 infection, especially CD4+ T-lymphocyte cell count, appeared to have the strongest association with the development of lipoatrophy.” These data, which indicate that progression of HIV disease affects the risk of lipoatrophy, are other factors that physicians and patients must consider when deciding the appropriate time to start antiretroviral therapy.

K. Lichtenstein and others. Incidence and Risk Factors for Lipoatrophy (Abnormal Fat Loss) in Ambulatory HIV-1-Infected Patients. Abstract 684a.