Centrally Located Visceral Adipose Tissue and Outcomes after Laparoscopic Gastric Banding Surgery

Hypothesis: A higher proportion of central VAT relative to total VAT leads to decreased efficacy of LGBS outcomes as measured by percent excess weight loss (%EWL), inflammatory marker, and insulin resistance. Method: Thirty-three LGBS patients (21 women, 12 men) underwent pre-surgical and 6-month (T2) post-surgical testing. Average age was 45.7 years (24-66). Average baseline Body Mass Index was 43.1 kg/m2 (32.4-54.0). Fasting blood samples were taken to assess cardiac C-reactive protein (CRP), insulin, and glucose. Homeostasis Model of Assessment score (HOMA) for insulin resistance was calculated using insulin and glucose. %EWL was calculated using number of pounds lost relative to number of baseline pounds above a BMI of 25. VAT was assessed using computed tomography. Proportion of central VAT was calculated as L4/L5 divided by total VAT. Patients were split into a Low- (LP) or High Proportion (HP) group based on a median split. Repeated measures t-tests were used to compare changes in CRP and HOMA from baseline to T2. Independent t- tests were used to compare differences between groups at T2 in CRP, HOMA, and %EWL. Results: Both LP and HP showed significant reductions from baseline to T2 in CRP (p=.026 and .000 respectively), and HOMA (both p=.001). There was no significant difference at T2 between LP and HP in %EWL or HOMA. A trend toward lower CRP at T2 for HP compared to LP was observed, although results were not significant (p=.08). Conclusion: Results of this analysis demonstrate that the relative proportion of centrally located VAT does not appear to be a significant factor in outcomes measured 6 months post-LGBS. Patients with higher or lower proportions exhibit improvements in HOMA and %EWL, although inflammation may not resolve as effectively for patients with higher proportions. Overall, it appears that the relative location of VAT does not appear to be a substantive factor in the efficacy of LGBS.