ORIGINAL ARTICLE Inpatient Costs for Patients with Inflammatory Bowel Disease and Acute Pancreatitis Aimee Alexoff, BS,* Grigory Roginsky, MD, † Ying Zhou, PhD, ‡ Michelle Kalenda, BS,* Kelly Minuskin, BS,* and Eli D. Ehrenpreis, MD, AGAF, FACG* ,§,k Background: Inflammatory bowel disease (IBD) is associated with an increased risk of acute pancreatitis (AP). Our group examined differences in length of stay and costs for patients with IBD hospitalized for AP and the general population. Methods: Using the National Inpatient Sample, we examined all admissions during 2005 to 2011 with a primary diagnosis of AP and codiagnosis of IBD. Continuous variables were reported as mean 6 SD and compared between IBD and controls. To compare the outcomes of interest, we conducted a 1:3 propensity score matching using a greedy algorithm based on age, gender, race, number of comorbidities, procedures, insurance, income quartiles, hospital bed size, hospital location, and teaching status. Statistical analyses were performed on SAS 9.3 (Cary, NC). Results: There were 4291 hospitalizations of patients with IBD and AP over the 7-year period and 379,627 hospitalizations of patients without IBD and with AP. More patients with Crohn’s disease developed AP than patients with ulcerative colitis (2145 versus 1219). The length of stay and costs for patients with AP and IBD were significantly higher than controls (5.7 days versus 4.9 days, P , 0.0001 and $29,724.89 versus $27,916.76, P , 0.0001). The percentage of patients with alcohol abuse was lower in patients with IBD than that of controls (11.8% versus 21.7%, P , 0.0001). However, the percentage of patients with IBD who were drug abusers was higher than controls (5.8% versus 4.3%, P , 0.0005). Conclusions: Our study suggests that a codiagnosis of Crohn’s disease or ulcerative colitis incurs a greater economic burden in patients with AP. (Inflamm Bowel Dis 2016;22:1095–1100) Key Words: inflammatory bowel disease, acute pancreatitis, outcomes C rohn’s disease (CD) and ulcerative colitis (UC) are chronic, relapsing-remitting immunologically mediated conditions of the gastrointestinal tract and other organs. At present, many as- pects of the etiologies responsible for the development of CD and UC are unknown. 1,2 Studies have suggested that the interaction between genetics, environment, and gut microbiota plays a role in the development of inflammatory bowel disease (IBD). 2–4 The prevalence of IBD has increased across the world over the last 50 years. 1,3,5 This may be partially due to the adaptation of west- ern lifestyles throughout the world, thus indicating the importance of environmental influences on the development of IBD. 6 It is estimated that roughly 1.5 million Americans and 2.2 million Europeans carry the diagnosis of IBD. 3 In North America, the incidence ranges from 0 to 19.2 per 100,000 and 0 to 20.2 per 100,000 for UC and CD, respectively. 3,5 With rates of IBD increasing, we can anticipate more reports of acute pancreatitis (AP) because IBD is associated with an increased risk of AP. 7 This increased risk may be due to the direct manifestations of the disease itself or a side effect of treat- ment. Common treatments of IBD include drugs from 2 classes: 5-aminosalicylates (mesalamine and sulfasalazine) and thiopur- ines (azathioprine and 6-mercaptopurine). 8 Multiple studies have shown that these classes of drugs cause drug-induced AP. 7,9,10 In the general population of the United States, the most common causes of AP are choledocholithiasis and alcohol abuse. 11 Accord- ing to the limited data available, the most common causes of AP in patients with IBD are choledocholithiasis and drugs used to treat IBD. 12 The extent to which alcohol is a common cause of AP in patients with IBD requires further investigation. 13 Previous studies have examined the overall length of stay (LOS) and cost of hospitalizations in patients with IBD and AP separately but have not evaluated these costs together. 14–17 It is anticipated that patients with IBD who are admitted for AP will have a more complex and costly hospitalization. Given the emphasis on reduction in hospital costs in general, our group sought to determine the economic effect of a codiagnosis of CD or UC in patients being hospitalized for AP. Received for publication November 19, 2015; Accepted December 17, 2015. From the *Center for the Study of Complex Diseases, Research Institute, North- Shore University HealthSystem, Evanston, Illinois; † Department of Medicine, Evanston Hospital, NorthShore University HealthSystem, Evanston, Illinois; ‡ Center for Biomedical Research Informatics, Research Institute, NorthShore University HealthSystem, Evanston, Illinois; § Department of Medicine, University of Chicago, Chicago, Illinois; and k Department of Gastroenterology, NorthShore University HealthSystem, Evanston, Illinois. Supported by a grant from the Keyser Family Fund. The authors have no conflict of interest to disclose. Reprints: Eli D. Ehrenpreis, MD, AGAF, FACG, Medical Director, Center for the Study of Complex Diseases, Research Institute, NorthShore University HealthSystem, 1001 University Place, Evanston, IL 60201 (e-mail: ehrenpreis@gi- pharm.net). Copyright © 2016 Crohn’s & Colitis Foundation of America, Inc. DOI 10.1097/MIB.0000000000000739 Published online 25 February 2016. Inflamm Bowel Dis  Volume 22, Number 5, May 2016 www.ibdjournal.org | 1095 Copyright © 2016 Crohn’s & Colitis Foundation of America, Inc. Unauthorized reproduction of this article is prohibited. Downloaded from https://academic.oup.com/ibdjournal/article-abstract/22/5/1095/4561763 by guest on 05 July 2020