Observational Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 28, 2015; 21(4): 1251-1260
Published online Jan 28, 2015. doi: 10.3748/wjg.v21.i4.1251
Colectomy is a risk factor for venous thromboembolism in ulcerative colitis
Gilaad G Kaplan, Allen Lim, Cynthia H Seow, Gordon W Moran, Subrata Ghosh, Yvette Leung, Jennifer Debruyn, Geoffrey C Nguyen, James Hubbard, Remo Panaccione
Gilaad G Kaplan, Allen Lim, Cynthia H Seow, Gordon W Moran, Subrata Ghosh, Yvette Leung, James Hubbard, Remo Panaccione, Inflammatory Bowel Disease Clinic, University of Calgary, Calgary AB T2N 4N1, Canada
Gilaad G Kaplan, Allen Lim, Cynthia H Seow, Gordon W Moran, Subrata Ghosh, Yvette Leung, James Hubbard, Remo Panaccione, Division of Gastroenterology, University of Calgary, Calgary AB T2N 4N1, Canada
Gilaad G Kaplan, Allen Lim, Cynthia H Seow, Gordon W Moran, Subrata Ghosh, Yvette Leung, James Hubbard, Remo Panaccione, Departments of Medicine, University of Calgary, Calgary AB T2N 4N1, Canada
Gilaad G Kaplan, Community Health Sciences, University of Calgary, Calgary AB T2N 4N1, Canada
Jennifer Debruyn, Paediatrics, University of Calgary, Calgary AB T2N 4N1, Canada
Geoffrey C Nguyen, Mount Sinai Centre for Inflammatory Bowel Disease, University of Toronto, Toronto ON M5S, Canada
Geoffrey C Nguyen, Institute for Clinical Evaluative Sciences, Toronto ON M5S, Canada
Author contributions: Kaplan GG conceived of the study; Kaplan GG, Nguyen GC, Leung Y, Seow CH, Debruyn J, Panaccione R, and Ghosh S participated in the design of the study; Lim A and Moran GW collected the data and developed the database; Kaplan GG and Hubbard J performed the statistical analysis; all authors interpreted the findings, helped to draft the manuscript and approved the final manuscript. Kaplan GG had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Supported by Alberta IBD Consortium, funded by Alberta Innovates Health Solutions.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Gilaad G Kaplan, MD, MPH, FRCPC, Associate Professor, Inflammatory Bowel Disease Clinic, Uni­versity of Calgary, 3280 Hospital Drive NW, Room 6D56, Calgary AB T2N 4N1, Canada. ggkaplan@ucalgary.ca
Telephone: +1-403-5925015 Fax: +1-403-5925090
Received: April 15, 2014
Peer-review started: April 16, 2014
First decision: July 9, 2014
Revised: August 5, 2014
Accepted: September 18, 2014
Article in press: September 19, 2014
Published online: January 28, 2015
Abstract

AIM: To compare venous thromboembolism (VTE) in hospitalized ulcerative colitis (UC) patients who respond to medical management to patients requiring colectomy.

METHODS: Population-based surveillance from 1997 to 2009 was used to identify all adults admitted to hospital for a flare of UC and those patients who underwent colectomy. All medical charts were reviewed to confirm the diagnosis and extract clinically relevant information. UC patients were stratified by: (1) responsive to inpatient medical therapy (n = 382); (2) medically refractory requiring emergent colectomy (n = 309); and (3) elective colectomy (n = 329). The primary outcome was the development of VTE during hospitalization or within 6 mo of discharge. Heparin prophylaxis to prevent VTE was assessed. Logistic regression analysis determined the effect of disease course (i.e., responsive to medical therapy, medically refractory, and elective colectomy) on VTE after adjusting for confounders including age, sex, smoking, disease activity, comorbidities, extent of disease, and IBD medications (i.e., corticosteroids, mesalamine, azathioprine, and infliximab). Point estimates were presented as odds ratios (OR) with 95%CI.

RESULTS: The prevalence of VTE among patients with UC who responded to medical therapy was 1.3% and only 16% of these patients received heparin prophylaxis. In contrast, VTE was higher among patients who underwent an emergent (8.7%) and elective (4.9%) colectomy, despite greater than 90% of patients receiving postoperative heparin prophylaxis. The most common site of VTE was intra-abdominal (45.8%) followed by lower extremity (19.6%). VTE was diagnosed after discharge from hospital in 16.7% of cases. Elective (adjusted OR = 3.69; 95%CI: 1.30-10.44) and emergent colectomy (adjusted OR = 5.28; 95%CI: 1.93-14.45) were significant risk factors for VTE as compared to medically responsive UC patients. Furthermore, the odds of a VTE significantly increased across time (adjusted OR = 1.10; 95%CI: 1.01-1.20). Age, sex, comorbidities, disease extent, disease activity, smoking, corticosteroids, mesalamine, azathioprine, and infliximab were not independently associated with the development of VTE.

CONCLUSION: VTE was associated with colectomy, particularly, among UC patients who failed medical management. VTE prophylaxis may not be sufficient to prevent VTE in patients undergoing colectomy.

Keywords: Inflammatory bowel diseases, Ulcerative colitis, Deep vein thrombosis, Pulmonary embolism, Surgery

Core tip: The occurrence of venous thromboembolism (VTE) in our population-based cohort was about 5%, which highlights the importance of this complication among hospitalized ulcerative colitis (UC) patients. However, the risk of VTE was low (about 1%) among flaring ulcerative colitis patients who responded to medical management. In contrast, UC patients who underwent an elective (5%) or emergent colectomy (8.7%) had higher occurrence of VTE. After adjusting for covariates the leading risk factor for VTE was the need for colectomy. VTE occurred in colectomy patients despite > 90% postoperative VTE prophylaxis. Thus, heparin prophylaxis may not be sufficient to prevent VTE in patients undergoing colectomy.