A prospective 4-year study of insulin resistance and adipokines in morbidly obese diabetic and non-diabetic patients after gastric banding.

There are insufficient data regarding the changes in adipokine levels after laparoscopic adjustable gastric banding (LAGB) in diabetic and non-diabetic patients and their effects on insulin resistance and type 2 diabetes remission.

To assess leptin, adiponectin, and insulin resistance changes after LAGB in diabetic and non-diabetic morbidly obese patients.

One hundred and three patients (37 with and 66 without type 2 diabetes) underwent LAGB from January 2009 to January 2010. Glycated hemoglobin, insulin, adipokine levels and insulin resistance were evaluated preoperatively, and 1 and 4 years after LAGB.

The mean patient age was 45.9 ±11.7 years and mean preoperative body mass index was 47.5 ±7.3 kg/m. A total of 80 of 103 patients (77.6%) completed the 4-year follow-up. After 4 years the mean excess weight loss was 38.8% and 39.5% in diabetic and non-diabetic patients respectively. Leptin levels decreased significantly in both groups at 1 year, but after 4 years this was noted only in non-diabetic patients. After 1 year adiponectin levels increased significantly only in non-diabetic patients (p = 0.003) and remained almost the same at 4 years. A significant decrease in insulin resistance was noted in both groups 1 year after LAGB and diabetes remission was observed in 23 (62.1%) patients. There was a negative correlation between preoperative insulin resistance and adiponectin levels throughout the follow-up period. Leptin levels positively correlated with BMI throughout the study period (baseline r = 0.45; p < 0.001; after 1 year r = 0.71; p < 0.001; after 4 years r = 0.68; p < 0.001). There was no significant correlation between leptin and adiponectin concentrations preoperatively or after 1 year; however, at 4 years it was significant (r = 0.27; p < 0.02).

The most significant metabolic changes occurred within 1 year after LAGB. The 4-year follow-up revealed stabilization in metabolic indices rather than significant improvement.