765 Low Skeletal Muscle Index Is an Independent Risk Factor for Inflammatory Bowel Disease Surgical Complications

Abstract

INTRODUCTION: Pre-operative assessment is necessary to determine if patients with inflammatory bowel disease (IBD) will benefit from nutrition support. The relationship between skeletal muscle area and the prognosis of patients who undergo surgery for IBD remains undetermined. This study aims to evaluate the skeletal muscle index (SMI) area as a predictive marker for surgical outcomes in patients with IBD. METHODS: Data were collected retrospectively for consecutive surgeries for IBD complications between March 2014 and April 2016. The primary outcome of interest was infectious and non-infectious post-operative complications. The SMI was measured using the cross-sectional computed tomography images at the mid-L3 level using ImageJ. Sarcopenia was defined using previously validated SMI categories adjusted for sex and BMI. Data were analyzed using Wilcoxon rank-sum test for continuous variables and Fischer's exact test for categorical variables. Multivariate logistic regression was performed to identify independent factors predictive of postoperative complications. RESULTS: 439 patients were included in the final analysis. 92 (20.1%) patient had cross-sectional imaging available for sarcopenia evaluation. 178 (40.5%) experienced post-operative complications. In univariate analysis, Crohn's disease, SMI, Nutrition Risk Index, albumin, CRP, and BUN were associated with increased risk of 30-day postoperative complications (Table 1). In multivariate analysis, only sarcopenia as defined by Martin et al. (OR = 5.6; CI: 1.7-18.3) was significantly predictive of postoperative complications. In subgroup analysis, sarcopenia was found to be predictive of infectious postoperative complications (57.1% versus 22%, P = 0.001). CONCLUSION: Skeletal muscle index utilizing previously defined categorical variables is a readily available and significant independent risk factor for 30-day postoperative complications in IBD with a strong association with infectious complications. Further interventional studies are required to define our abilities to mitigate post-operative complications based on these findings.