BMI: A Strong and Independent Predictor of Survival in HIV

Summary of published research¹

The identification of basic prognostic indicators of HIV infection is essential before widespread antiretroviral therapy can be implemented in low-technology settings. A recent study assessed how well body mass index (BMI:kg/m2) predicts survival.

BMI within 3 months of HIV diagnosis was obtained from 1657 patients aged >15 years, recruited in a seroprevalent clinical cohort in The Gambia since 1992, and followed up at least once. Baseline CD4+ counts and clinical assessment at time of diagnosis were collated.

The mortality hazard ratio (HR) of those with a baseline BMI <18 compared with those with a baseline BMI > 18 was 3.4 (95% CI, 3.0-3.9). The median survival time of those presenting with a BMI <16 was 0.8 years, in contrast to a median survival of 8.9 years for those with a baseline BMI >22. Baseline BMI <18 remained a highly significant independent predictor of mortality after adjustment for age, sex, cotrimoxazole prophylaxis, tuberculosis, reported wasting at diagnosis, and baseline CD4+ cell count (adjusted HR = 2.5, 95% CI 2.0-3.0). Sensitivity and specificity of baseline BMI <18 was comparable to that of a CD4+ count <200 in predicting mortality within 6 months of diagnosis.

BMI at diagnosis is a strong, independent predictor of survival in HIV-infected patients in West Africa. In the absence of sophisticated clinical and laboratory support, BMI may also prove a useful guide for deciding when to initiate antiretroviral therapy.

¹Marianne AB van der Sande, Maarten F.Schim van der Loeff, Akum A. Aveika, Saihou Sabally, Toyin Togun, Ramu, Sarge- Njie, Abraham S. Alabi, Assan Jaye, Tumani Corrah, and Hilton C. Whittle, (2004). Body Mass Index at Time of HIV Diagnosis. A Strong and Independent Predictor of Survival. J Acquir Immune Defic Syndr 2004;37:1288-1294