Beneficial effects of protease inhibitors on body composition and energy expenditure: a comparison between HIV-infected and AIDS patients

Objectives: (i) To investigate whether protease inhibitor (PI) (nelfinavir) -containing highly active antiretroviral therapy (HAART) affects body compo sition differently in HIV-infected and AIDS patients without wasting syndro me. (ii) To delineate the changes in resting energy expenditure (REE) under P1 therapy, and to determine whether sustained reductions in HIV RNA would decrease REE, Design: Prospective longitudinal cohort study with individually matched hea lthy controls. Setting: Tertiary care centre at a University Hospital. Methods: HIV-seropositive (n = 20) and AIDS patients (n = 17) with a plasma viral load of at least 10000 copies/ml and 37 healthy volunteers were enro lled. All participants were weight stable, free of acute opportunistic infe ctions, and naive to PI therapy. Patients underwent testing of bioelectrica l impedance analysis (BIA), indirect calorimetry and food intake, shortly b efore the initiation of HAART and 24 weeks thereafter. Results: Both patient groups gained weight, body mass index (BMI), and fat- free mass (FFM) (P < 0.05 versus baseline), whereas only AIDS patients gain ed fat mass. Increases were more pronounced in the AIDS group. REE was elev ated compared with corresponding controls at baseline, and decreased simila rly in HIV and in AIDS patients during PI therapy (P < 0.05). The reduction in the viral burden preceded the decrease in REE by several weeks. Conclusion: Body composition and metabolic parameters improved during PI th erapy in HIV-infected and AIDS patients without wasting. Although an early reduction in viral load as a result of HAART does not seem to influence REE directly, sustained viral load suppression may promote ct decrease in ener gy expenditure. (C) 1999 Lippincott Williams & Wilkins.