Short-term energy restriction reduces resting energy expenditure in patients with HIV lipodystrophy and hypermetabolism.

We have previously shown that resting energy expenditure (REE) is increased in patients with HIV lipodystrophy. This hypermetabolism could be the result of an inadequate storage capacity for lipid fuel secondary to atrophy of the subcutaneous adipose tissue depot. Therefore, energy restriction may be able to alleviate this hypermetabolism. To test this hypothesis, we measured REE in HIV-infected patients with lipodystrophy and hypermetabolism and in HIV-infected and healthy controls. Measurements were taken during the overnight fasted state after 3 days on a eu-energetic diet and again after 3 days on a diet of similar composition but reduced in energy by 50%. After 3 days of eu-energetic feeding, REE was significantly higher in HIV-infected patients with lipodystrophy compared with healthy controls (139.5 +/- 1.3 vs 117.2 +/- 1.3 kJ/kg lean body mass, P < .001) and tended to be higher compared with HIV-infected subjects without lipodystrophy (139.5 +/- 13 vs 127.3 +/- 1.4 kJ/kg lean body mass, P = .06). Furthermore, energy restriction caused a significant decline in REE in patients with HIV lipodystrophy (P < .001). This dietary manipulation did not lead to a significant reduction in REE in either HIV-infected or healthy controls. This suggests that energy intake and REE may be uniquely coupled in patients with lipodystrophy as a means to dissipate energy that cannot be stored in a normal manner. A better understanding of this coupling would have important implications for weight regulation in general.