Overcoming metabolic syndrome in severe obesity: adiponectin as a marker of insulin sensitivity and HDL-cholesterol improvements after gastric bypass.

OBJECTIVE: To assess the relationship between adiponectin and metabolic parameters in severely obese women during surgical-induced weight loss.
METHODS: Nineteen lean (CT - BMI:21.2 +/- 0.3 kg.m(2)), 14 overweight/class II obese (OB/OW - BMI: 29.7 +/- 0.7 kg/m(2)) and 8 morbidly obese (OBIII - BMI: 56.4 +/- 3.6 kg/m(2)) were evaluated by hyperinsulinemic-euglycemic clamp, adiponectin, and lipids. OBIII were evaluated at 5th and 16th month post-operatively.
RESULTS: Compared to lean, obese groups had lower adiponectin (OB/OW: 9.4 +/- 0.9, OBIII: 7.1 +/- 1.3 versus 12.2 +/- 0.9 ng/dL; p < 0.01), lower HDL-cholesterol (OB/OW:1.05 +/- 0.05, OBIII: 0.88 +/- 0.04 versus 1.22 +/- 0.07 mmol/L; p < 0.01) and insulin resistance-IR (glucose uptake, M-value - OB/OW: 43.6 +/- 2.7, OBIII: 32.4 +/- 3.2 versus 20.0 +/- 1.8 umol/kgFFM.min; p < 0.001). Considering all subjects, adiponectin levels were inversely correlated to BMI and waist circumference, and directly to M-value and HDL-cholesterol (p < 0.01). During weight loss, improvements in IR (Study III: 36.1 +/- 3.9 umol/kg/FFM.min, p < 0.0001), adiponectin (11.8 +/- 1.4 ng/dL, p = 0.006) and HDL-cholesterol were observed (1.10 +/- 0.04 mmol/L, p = 0.007). Moreover, HDL-cholesterol improvement was significantly and independently related to variations of adiponectin and BMI (r(2) = 0.86; p < 0.0002).
CONCLUSIONS: The improvements of IR and adiponectin were related to surgical-induced weight loss, suggesting an important role of adiponectin in HDL-cholesterol regulation.