Backround: We previously reported that resting energy expenditure (REE) per kg LBM is increased in protease inhibitor (PI)-treated patients with HIV-associated lipodystrophy (LD). To determine whether total EE (TEE) is increased in HIV-LD, PI-treated HIV-infected men with and without LD were studied by whole-room indirect calorimetry and compared to healthy uninfected controls.

Methods: TEE and nutrient oxidation rates were assessed by whole-room indirect calorimetry while consuming a diet that contained 55% carbohydrate, 30% fat, and 15% protein. Subjects underwent a modest exercise regimen in the chamber. REE was measured using the open circuit technique. Body composition was assessed by DEXA and physical exam. Groups were compared using one-way ANOVA.

Results:  Mean CD4 counts were 457+236 cells/mL and 711+312 cells/L for the HIV+ men with/without LD, respectively; median plasma HIV-1 RNA was <200 copies/mL in both groups.  Body composition and EE studies (mean + SD):

                                                              HIV+ LD (12)            HIV+controls (6)         HIV-controls(16)

BMI (kg/m2)	24.3 + 3.8	25.2 + 1.9	23.8 + 1.9
% body fat	18.3 + 5.6	17.8 + 2.3	17.2 + 6.2
Lean body mass (kg)	57.9 + 6.3	62.7 + 6.7	59.9 + 6.1
TEE(kcal)/kg LBM/d	48.6 + 2.7	43.2 + 5.5*	40.9 + 4.4†
REE(kcal)/kg LBM/d	36.7 + 3.7	30.7 + 4.4*	28.9 + 2.3†
Carbohydrate oxidation**	6.04 + 1.4	5.0 + 0.9	4.4 + 1.4†

*p < 0.05; HIV-infected subjects with LD vs HIV-infected controls. ^†p <0.01;HIV-infected subjects with LD vs uninfected controls.  **gm/kg LBM/d

Conclusions: HIV-infected men with LD had increased REE/ kg LBM and TEE/kg LBM compared to HIV+ and HIV- controls. Carbohydrate oxidation was increased in subjects with LD. LD in HIV-uninfected patients is also characterized by increased EE, suggesting a common mechanism.