Effect of malabsorption on nutritional status and resting energy expenditure in HIV-infected patients

Abstract

To assess the influence of malabsorption on nutritional status and energy expenditure in patients at different stages of HIV infection.

Fifty HIV patients were classified into three groups: Group 1, HIV asymptomatic patients (n = 17); Group 2, AIDS without opportunistic infection (n = 16); Group 3, AIDS patients with active infection (n = 17). Clinically-healthy subjects (n = 19) were used as controls. Parameters measured were: anthropometry, body composition by tetrapolar bioelectrical impedance; resting energy expenditure (REE) by open-circuit indirect calorimetry; malabsoption by D-xylose absorption and triolein breath tests.

Malabsorption (defined as abnormality of xylose and/or fat absorption test) was found in 34 (68%) of patients: 9 (53%) Group 1; 11 (69%) Group 2; 14 (82%) Group 3. Twenty-seven (54%) had sugar malabsorption and 21 (42%) fat malabsorption. A significant relationship was observed between malabsorption and weight loss. REE measured was significantly lower in malabsorptive patients than in non-malabsorptive patients and controls (6006.3 ± 846.5 versus 6443.4 ± 985.5 versus 6802.1 ± 862.7 kJ/day, respectively; P <0.05). The REE adjusted for fat-free mass was lower in malabsorptive than in non-malabsorptive patients and slightly higher than in controls, although the differences were not statistically significant.

The results suggest that malabsorption is a frequent feature in HIV infection and is related to the HIV-related weight loss. Hypermetabolism is not a constant phenomenon in HIV infection since, in the presence of malabsorption, our patients show an appropriate metabolic response with a compensatory decrease in REE.