# A179 A CANADA-WIDE STUDY OF TRENDS IN HOSPITALIZATION RATES FOR INFLAMMATORY BOWEL DISEASE

## TL;DR

This study examines how hospitalization rates for inflammatory bowel disease have changed in Canada from 2002 to 2014 and predicts future trends.

## Contribution

The study provides a Canada-wide analysis of IBD hospitalization trends and forecasts future rates using population-based data.

## Key findings

- Hospitalization rates for IBD decreased from 2002 to 2014 across all age, sex, and IBD subtypes.
- Despite declining rates, the actual number of hospitalizations increased due to rising IBD prevalence.
- Forecasted rates for 2025 suggest continued decline in hospitalization rates but an increase in counts.

## Abstract

Hospitalizations among individuals with inflammatory bowel disease (IBD) place a strain on healthcare resources. The decline in hospitalization rates during the era of anti-TNF therapies remains debated in the literature.

To examine temporal trends in hospitalization rates among individuals with in IBD across Canada.

We used population-based administrative healthcare data (2002–2014) from seven Canadian provinces (AB, BC, MB, NS, QC, ON, SK) to identify hospitalizations in prevalent IBD cases. Hospitalizations were categorized as: 1. all-cause, any hospitalization of an IBD patient; 2. IBD-related, admission for IBD or symptoms/comorbidities associated with IBD (eg. venous thromboembolism). We calculated hospitalization rates per 100 IBD persons with 95% confidence intervals (CIs) using IBD prevalence data. Hospitalization rates were forecast from 2015–2025, with 95% prediction intervals (PIs), using auto regressive integrated moving average models on log transformed data. We calculated average annual percentage change (AAPC) using Poisson models with quadratic equations applied for non-linear trends. We stratified by IBD subtype (CD, UC), age (<18, 18–64, 65+), and sex (female, male). We calculated AAPCs for counts to assess the actual number of hospitalizations.

From 2002–2014, hospitalizations rates decreased for both all-cause and IBD-related admissions for IBD patients, and across age, sex, and IBD type (Table 1). In 2025, we forecast hospitalization rates to be 15.82 (95%CI:14.17,17.66) per 100 for all-cause and 7.87 (95%CI:6.16,9.90) per 100 for IBD-related. Hospitalization rates are falling, but AAPCs for hospitalization counts significantly increased for all-cause (2.65%; 95%CI: 2.42,2.89) and IBD-related (1.52%; 95%CI: 1.29,1.76). The disparity between decreasing rates and increasing counts is due to the faster rise in the AAPC of IBD prevalence (denominator) compared to hospital counts (numerator).

During the anti-TNF era (2002–2014), hospitalization rates for IBD steadily declined across Canada and are projected to continue decreasing through 2025. Despite this decline, the actual number of hospitalizations is increasing, likely driven by the rising prevalence of IBD.

¥ Includes IBD-Unclassified *Non-linear

CIHR