THE COST OF INFLAMMATORY BOWEL DISEASE: A POPULATION-BASED ANALYSIS OF ADMINISTRATIVE DATA
Authors: Coward Stephanie , Windsor Joseph , Benchimol Eric , Bernstein Charles , Avina-Zubieta Antonio , Bitton Alain , Hracs Lindsay , Jones Jennifer , Kuenzig Ellen , Lu Na , Ma Christopher , Murthy Sanjay , Nugent Zoann , Otley Anthony , Panaccione Remo , Pena-Sanchez Juan Nicolas , Singh Harminder , Targownik Laura , Kaplan Gilaad 
Published: January 2024

Abstract

BACKGROUND
As the global prevalence of inflammatory bowel disease (IBD) rises, it is important that the direst costs associated with medical care be analyzed to determine the impact on healthcare systems. Components making up the direct healthcare cost to the IBD population (e.g., hospitalizations, colonoscopies, and medications) are constantly changing and with this so may be the cost related to taking care of the IBD population.

AIM
Analyze component-specific costs, total costs, and the proportion of total costs attributed to each component, and changes over time.

METHODS
Using a validated algorithm and population-based administrative data from Alberta, Canada (Population: 4.3m), prevalent IBD patients were identified from fiscal year (FY) 2009/10 to 2018/19 (April 1–March 31). Costs from the Discharge Abstract Database, Physician Claims, National Ambulatory Care, and Pharmacy Information Network were converted to 2020 (CAD$) costs using Statistics Canada’s Consumer Price Index. Only IBD-related outpatient dispensed medications were included in the costs (inpatient not captured in data). Annual average costs per patient (with 95% confidence interval [CI]) were calculated. Medication costs per person were stratified on whether or not an individual was on a biologic (e.g. anti-TNF therapy) versus a non-biologic IBD-related medication (e.g., 5-ASA). The cost of an individual’s IBD-related hospitalization, IBD-related surgery, emergency department visit, colonoscopy, or IBD-related medication were calculated. Proportion of the total costs contributed by each category were calculated. Temporal trends of mean annual costs were analyzed using Poisson, or negative binomial, regression and average annual percentage change (AAPC) with 95%CI were reported.

RESULTS
In FY2018/19, the average cost of an IBD patient was $15,786 (95%CI:15,478, 16,094). This cost significantly increased from the 2009 value ($8,477; 95%CI: 8,407, 8,908) with an AAPC of 6.28% (95%CI: 5.51, 7.05). The annual costs of medications when a patient is on one or more biologics significantly increased (AAPC: 3.48%; 95%CI:2.32, 4.65). In contrast, the average annual cost per patient of IBD-related non-biologic medications significantly decreased (AAPC: -2.32; 95%CI: -3.48, -1.14). The largest contributor to IBD costs is medications (57.6% of the total costs) followed by IBD-related hospitalizations (20.6%). The costs of IBD-related hospitalizations and surgeries have remained stable, whereas the costs for emergency department visits and colonoscopies increased.

DISCUSSION
The costs associated with treating people IBD is rising and predominantly attributable to the cost of biologics. As the prevalence of IBD continues to increase, healthcare systems, payers and governments need to work to address these costs while ensuring these individuals receive the care they need.

*Proportions will not add up to 100% as individuals can be captured in multiple cost categories each year (e.g., an IBD-related surgery cost is also captured as a hospitalization) and not all costs are reported in table.

Overall and Biologics are Per Person; Hospitalization and Sugery are Per Event