Retrospective Cohort Study
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Pharmacol Ther. Jun 5, 2025; 16(2): 105335
Published online Jun 5, 2025. doi: 10.4292/wjgpt.v16.i2.105335
Comorbidities and systemic steroids drive pneumonia risk in inflammatory bowel disease: Propensity score-matched cohort study
Yong Eun, Joan Culpepper-Morgan, Abiodun M Akanmode, Myint B Thu, Aprilee A Sta Lucia, Marie S Thearle, Rhonda K Trousdale
Yong Eun, Abiodun M Akanmode, Myint B Thu, Aprilee A Sta Lucia, Marie S Thearle, Department of Medicine, NYC Health + Hospitals/Harlem, New York, NY 10037, United States
Joan Culpepper-Morgan, Division of Gastroenterology, Department of Medicine, NYC Health + Hospitals/Harlem, New York, NY 10037, United States
Joan Culpepper-Morgan, Rhonda K Trousdale, Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, United States
Rhonda K Trousdale, Division of Endocrinology, Department of Medicine, NYC Health + Hospitals/Harlem, New York, NY 10037, United States
Author contributions: Eun Y and Culpepper-Morgan J designed the study; Eun Y and Thearle MS were responsible for developing the methodology; Eun Y and Thearle MS participated in the statistical analyses and investigation; Eun Y, Akanmode AM, Thu MB, and Sta Lucia AA wrote the original draft; Eun Y, Culpepper-Morgan JA, Akanmode AM, Thu MB, Sta Lucia AA, Thearle MS, and Trousdale RK participated in the review and editing; All authors have read and approved the final manuscript.
Supported by The Interdisciplinary Guided Network for Investigation, Translation and Equity for the All of Us Research Program, No. OT2 OD031915.
Institutional review board statement: The study protocol was reviewed and approved by the Institutional Review Board (IRB) of the All of Us Research Program. The All of Us Researcher Workbench employs a data passport model, through which authorized users do not need IRB review for each research project.
Informed consent statement: Our project which used de-identified All of Us data accessed and analyzed through the Researcher Workbench, a cloud-based platform for approved researchers, did not meet the definition of human subject research, and was exempt from IRB review. As such, written or verbal informed consent was waived by the All of Us IRB.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement checklist of items.
Data sharing statement: Data, analytic methods, and study materials are available through the All of Us Research Program’s Researcher Workbench platform (https://www.researchallofus.org/).
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Yong Eun, MD, Department of Medicine, NYC Health + Hospitals/Harlem, No. 506 Lenox Ave, New York, NY 10037, United States. euny@nychhc.org
Received: January 20, 2025
Revised: April 10, 2025
Accepted: May 13, 2025
Published online: June 5, 2025
Processing time: 136 Days and 1.8 Hours
Abstract
BACKGROUND

Patients with inflammatory bowel disease (IBD) are at an increased risk of bacterial pneumonia, contributing to significant morbidity and mortality. While previous studies have identified various risk factors, including medications and comorbidities, the independent contribution of IBD to pneumonia risk remains unclear. We hypothesized that the increased pneumonia risk is primarily driven by factors other than IBD itself.

AIM

To investigate the relative contributions of IBD, comorbidities, and medications to pneumonia risk in patients with IBD.

METHODS

We conducted a retrospective cohort study using the All of Us Research Program database (2010-2022). We matched 2810 participants with IBD 1:1 with controls using four propensity score models: (1) Demographics/Lifestyle only; (2) Plus comorbidities; (3) Plus medications; and (4) All factors combined. Then we used Cox proportional hazards models to assess pneumonia risk and logistic regression to evaluate risk factors.

RESULTS

In the primary analysis of 5620 matched participants, IBD was not independently associated with increased pneumonia risk [hazard ratio (HR) = 1.07, 95%CI: 0.84-1.35] when matched for all factors. However, participants with IBD had significantly higher risk (HR = 2.08, 95%CI: 1.56-2.78) when matched only for demographics and lifestyle factors. Within the IBD cohort, a high comorbidity burden (Charlson Comorbidity Index ≥ 10) [odds ratio (OR) = 12.20, 95%CI: 6.69-23.00] and systemic steroid use (OR = 2.26, 95%CI: 1.21-4.64) were independently associated with increased pneumonia risk.

CONCLUSION

Comorbidities and systemic steroids, rather than IBD itself, drive pneumonia risk. Management should focus on these factors and prioritize vaccination in high-risk patients.

Keywords: Inflammatory bowel disease; Bacterial pneumonia; Comorbidity burden; Systemic steroids; Propensity score matching; Risk factor analysis; Immunosuppressive therapy; Pneumococcal vaccination

Core Tip: While increased pneumonia risk in inflammatory bowel disease (IBD) is well-documented, this large propensity-matched study of 5620 participants provides novel insights into its underlying drivers. Using multiple propensity score models, we demonstrate that the heightened pneumonia risk is primarily driven by comorbidities and systemic steroid use, rather than IBD itself. Most notably, patients with a high Charlson Comorbidity Index (≥ 10) showed a 12-fold increased risk, while systemic steroid use doubled the risk. These findings suggest that pneumonia prevention strategies in IBD should prioritize comorbidity management and judicious steroid use, particularly in high-risk patients.