Diet-induced thermogenesis in HIV infection

To assess whether postprandial dietary thermogenesis contributes to weight loss during HIV infection.

The thermogenic response to a test meal (15 kcal/kg) was evaluated with indirect calorimetry in 16 HIV-infected patients in a stable condition and compared with a control group. Patients were compared according to AIDS (n = 8) or non-AIDS (n = 8) status and to body weight loss (WL; n = 9) or no loss (NL; n = 7). Indirect calorimetry was performed after fasting 6 h and during 5 h after the test meal.

Maximum value of energy expenditure was reached later in the WL group than in the control and NL group (200 versus 30 min, respectively). Energy expenditure returned to the initial value 300 min after the test meal (last measurement) in the control group but remained elevated in the patient group. Energy expenditure after food intake was more elevated in HIV-infected patients than in controls, especially in patients with detectable clinical change in their nutritional status (0.96 versus 0.72 kcal/kg body weight).

Both kinetics and quantitative aspect of dietary thermogenesis are modified during HIV infection and the different variations are dependent on the extent of body weight loss.