Weight loss after Swedish Adjustable Gastric Banding: relationships to insulin resistance and metabolic syndrome.

Background: The metabolic syndrome is a cluster of cardiovascular risk factors (central obesity, hypertension, dyslipidemia, disturbance in glucose metabolism) associated with insulin-resistance. The cluster of risk factors defining the metabolic syndrome increases cardiovascular risk more than each single component. The aim of the present longitudinal study was to evaluate the relationship between weight loss and changes in insulin-resistance and in the prevalence of the metabolic syndrome 1-year after SAGB implantation.

Methods: 51 premenopausal severely obese women (mean age 35.2 +/- 8.8 years, BMI 43.3 +/- 6.9) were enrolled. As a control group, 51 premenopausal non-obese women (BMI < 30) were enrolled. All obese subjects underwent successful implantation of the SAGB via videolaparoscopy. In all subjects insulin-resistance was estimated by HOMA index and metabolic syndrome was defined according to the criteria of the European Group for the Study of Insulin Resistance.

Results: HOMA (4.2 +/- 2.0 vs 1.9 +/- 0.8, P < 0.001) and the prevalence of the metabolic syndrome (58.8% vs 7.8%, P < 0.001) were significantly higher in obese than non-obese women. 1 year after SAGB, BMI significantly decreased from 43.3 +/- 6.9 to 34.5 +/- 7.4 (P < 0.001). HOMA index showed a significant dramatic breakdown (4.2 +/- 2.0 vs 2.4 +/- 1.0, P < 0.001). The prevalence of the metabolic syndrome declined significantly (58.8% vs 21.6%, P < 0.001).

Conclusion: Our study shows that in severely obese women, insulin-resistance and the prevalence of the metabolic syndrome significantly decrease 1 year after SAGB. Our findings indicate that SAGB could be a useful tool to reduce the global cardiovascular risk in severely obese people and to improve their long-term prognosis.