Backround: HIV lipodystrophy (LD) is associated with insulin resistance (IR). Despite recent evidence for the role of adipocyte-derived hormones in IR, little is known about their levels in lipodystrophic states. To determine if adipocyte-derived hormone levels are altered in the HIV-LD syndrome, plasma leptin and adiponectin levels were measured in HIV+ men with and without LD.

Methods: Plasma leptin was measured by ELISA and adiponectin by RIA. Body composition was assessed by DEXA and CT. Insulin sensitivity (S_I)was measured by FSIGTT. Group means were compared by t-test.

Results: Leptin levels were higher (5.2 versus 2.9 ng/ml, p < 0.01) and adiponectin levels were lower (1.6 versus 4.0 mg/ml, p < 0.01) in the HIV-LD group as compared to controls. Correlation coefficients are shown below. Both leptin and adiponectin levels were strongly correlated with S_I and both were independent predictors of insulin sensitivity in a regression model where the possible predictors of S_I also included age, % body fat, fat mass, VAT, % of body fat in the trunk and % of body fat in the extremities.

Correlation coefficients

	Leptin	Adiponectin
% body fat	0.57*	0.27
Fat mass	0.69*	0.12
VAT	0.52*	-0.30
SAT	0.53*	0.38*
% trunk fat	0.03	-0.67*
% extremity fat	0.02	0.66*
SI	-0.48*	0.57*

Data are presented as Pearson product correlation coefficients: *p < 0.05

Conclusions: Leptin and adiponectin levels are altered in the HIV-LD. Leptin levels correlate with measures of adiposity and adiponectin with measures of body fat distribution.  The levels of these hormones are strongly correlated with and independent predictors of insulin sensitivity in the HIV-LD. Adiponectin deficiency may contribute to the insulin resistance of this LD syndrome.