The Effects of Weight Loss due to Gastric Banding and Lifestyle Modification on Red Blood Cell Aggregation & Deformability in Severe Obese Subjects

Objective:To investigate the changes in the aggregation index (AI) and the elongation index (EI), in severe obese subjects (MbObS) undergoing laparoscopic adjustable gastric banding (LAGB). AI and EI are measured by Laser assisted Optical Rotational Red Cell Analyzer (LORCA) and are markers of erythrocyte aggregation and deformability, respectively.Design and subjects:Before, 3 and 6 months after LAGB plus lifestyle changes (Mediterranean diet plus daily moderate exercise), we evaluated AI, EI, body mass index (BMI), total (ToT) cholesterol (Chol), high-density lipoprotein (HDL)-Chol, low-density lipoprotein (LDL)-Chol, triglycerides and fasting glucose and insulin levels in 20 MbObS. The Student's t-test was used for comparisons between independent groups and the analysis of variance to assess differences in AI and EI at the 3 time points. Pearson's correlation coefficient was used to assess correlation among continuous variables and multiple linear regression analysis to assess predictive factors for AI and EI changes.Results:BMI and all blood parameters showed a statistically significant decline 3 and 6 months after LAGB as compared with basal, except for EI and HDL-Chol that significantly increased. Stepwise selection of predictors shows that at 3 and 6 months, EI values depended on HDL-Chol values at the same time point. In the EI model, blood glucose was also statistically significant at 6 months.Conclusion:Our data show a significant improvement in EI after LAGB-induced weight loss, which correlates with an improved lipid pattern and support the idea that the rapid weight loss induced by LAGB plus lifestyle changes might reduce the thromboembolic risk and the high mortality risk found in MbObS.International Journal of Obesity advance online publication, 24 May 2011; doi:10.1038/ijo.2011.9