Obesity Is Associated With Increased Colectomy Rates and Hospitalization Charges in Patients With Ulcerative Colitis Flare: A Nationwide Outcome Analysis: 2017 Fellows-in-Training Award (Obesity Category): 2017 Presidential Poster Award

Abstract

Introduction: Although uncommon in the past, the obesity rates have increased in recent years in patients with ulcerative colitis (UC). Due to the paucity of cases, the effect of obesity in the history of natural disease in UC is unclear. We aimed to determine if there is any difference in outcomes of patients admitted to the hospital with UC flare in presence of obesity vs non-obese controls. Methods: A retrospective cohort study was done using the United States 2013 National Inpatient Sample, the largest publically available inpatient database in the United States. All patients with ICD-9 CM codes for a primary diagnosis of UC were included. No exclusion criteria were used. We considered in-hospital mortality as primary outcome. Secondary outcomes were morbidity measured by colectomy, intensive care unit (ICU) admission, shock, multi-organ dysfunction (MOD) and malnutrition; resource utilization measured by abdominal ultrasound (US), abdominal CT scan (ACT), length of hospital stay (LOS), total parenteral nutrition (TPN) use, total hospitalization charges (TOC) and colonoscopy. Patients were classified as obese or non-obese diagnosis based on ICD-9 CM codes. Odds ratios and means were calculated using multivariate regression analysis, after being adjusted for age, sex, race, Charlson Comorbidity Index, median income in the patient's zip code, hospital region, rural location, size and teaching status. Results: A total of 37,610 patients with UC flare were included. Mean age was 44.6 years and 52.4% were female. 2,460 (6.5%) were obese. In-hospital mortality rate was 0.54% overall, 0.6% in obese and 0.54% in non-obese patients. Adjusted odds ratios, means and p values are shown in Table 1. On multivariate analysis, obese patients did not have higher in-hospital mortality rates (OR 1.02, 95% CI 0.31-3.36; p=0.97) compared to the non-obese population. Notably, in the morbidity analysis, the obese patients with UC had higher risk of colectomy (OR 1.84, 95% CI 1.39 - 2.45; p < 0.001), although no difference in shock, ICU admission or MOD differences were found. For resource utilization, total charges were higher in the obese group; no difference was found in LOS, US, TPN and ACT use between both groups.Table: Table. Odds ratio and p-values for mortality, morbidity and resource utilization in obese versus non-obese patients with ulcerative colitisConclusion: Obesity in patients presenting with ulcerative colitis flare is associated with increased risk of colectomy and higher hospitalization charges, without affecting other morbidity, resource utilization and mortality outcomes.