Fat distribution and metabolic changes are strongly correlated and energy expenditure is increased in the HIV lipodystrophy syndrome

Objective: To examine the relationships between protease inhibitor (PI) the rapy, body fat distribution and metabolic disturbances in the HIV lipodystr ophy syndrome. Design: Cross-sectional study. Setting: HIV primary care practices. Patients: PI-treated patients with lipodystrophy (n = 14) and PI-treated (n = 13) and PI-naive (n = 5) patients without lipodystrophy. Main outcome measures: Body composition was assessed by physical examinatio n, dual-energy X-ray absorptiometry and computed tomography. Insulin sensit ivity (SI) was measured using the insulin-modified frequently sampled intra venous glucose tolerance test. Lipid profiles, other metabolic parameters, duration of HIV infection, CD4 lymphocyte counts, HIV-1 RNA load and restin g energy expenditure (REE) were also assessed. Results: PI-treated patients with lipodystrophy were significantly less ins ulin sensitive than PI-treated patients and PI-naive patients without any c hanges in fat distribution (S-I(22) X 10(-4) (min(-1)/muU/mI) versus 3.2 X 10(-4) and 4.6 X 10(-4) (min(-1)/muU/ml), respectively; P < 0.001). Viscera l adipose tissue area and other measures of central adiposity correlated st rongly with metabolic disturbances as did the percent of total body fat pre sent in the extremities; visceral adipose tissue was an independent predict or of insulin sensitivity and high density lipoprotein cholesterol levels. REE per kg lean body mass was significantly higher in the group with lipody strophy compared to the groups without lipodystrophy (36.9 versus 31.5 and 29.4 kcal/kg lean body mass; P < 0.001), and S, was strongly correlated wit h and was an independent predictor of REE in this population. Conclusions: Body fat distribution and metabolic disturbances are strongly correlated in the HIV lipodystrophy syndrome and REE is increased. (C) 2001 Lippincott Williams & Wilkins.