Weight change after antiretroviral therapy and mortality

Abstract

Background: Weight gain after antiretroviral therapy (ART) initiation is common, but its implication for mortality is unknown. We evaluated weight change in the first year after ART initiation and its association with subsequent mortality.

Methods: Human immunodeficiency virus-infected patients from the Veterans Aging Cohort Study (VACS) who initiated ART between 2000 and 2008, with weight recorded at baseline and 1 year later, were followed another 5 years for mortality. Baseline body mass index (BMI) was classified as underweight (<18.5 kg/m(2)), normal (18.5-24.9 kg/m(2)), overweight (25-29.9 kg/m(2)), and obese (≥30 kg/m(2)). We used multivariable Cox models to assess mortality risk with adjustment for disease severity using the VACS Index.

Results: The sample consisted of 4184 men and 127 women with a mean age of 47.9 ± 10.0 years. After 1 year of ART, median weight change was 5.9 pounds (2.7 kg) (interquartile range, -2.9 to 17.0 pounds, -1.3 to 7.7 kg). Weight gain after ART initiation was associated with lower mortality among underweight and normal-weight patients. A minimum threshold of 10- to 19.9-pound (4.5 to 9.0 kg) weight gain was beneficial for normal-weight patients (hazard ratio, 0.56; 95% confidence interval, .41-.78), but there was no clear benefit to weight gain for overweight/obese patients. Baseline weight, CD4 cell count status, and hemoglobin level were strongly associated with weight gain. Risk for weight gain was higher among those with greater disease severity, regardless of weight at initiation.

Conclusions: The survival benefits of weight gain after ART initiation are dependent on starting BMI. Weight gain after ART is associated with lower mortality for those who are not initially overweight.

Keywords: BMI; HIV; antiretroviral therapy; veterans; weight.