High healthcare costs in childhood inflammatory bowel disease: development of a prediction model using linked clinical and health administrative data

Background — The incidence of pediatric-onset inflammatory bowel disease (IBD) and the costs of caring for individuals with IBD are both increasing. We calculated the direct healthcare costs of pediatric IBD in the first year after diagnosis and developed a model to predict children who would have high costs (top 25th percentile).

Methods — Using data from the Canadian Children IBD Network inception cohort (≤16 years of age, diagnosed between 2013 and 2019) deterministically linked to health administrative data from Ontario, Canada, we estimated direct healthcare and medication costs accrued between 31 and 365 days after diagnosis. Candidate predictors included age at diagnosis, sex, rural/urban residence location, distance to pediatric center, neighborhood income quintile, IBD type, initial therapy, disease activity, diagnostic delay, health services utilization or surgery around diagnosis, regular primary care provider, and receipt of mental health care. Logistic regression with stepwise elimination was used for model building; 5-fold nested cross-validation optimized and improved model accuracy while limiting overfitting.

Results — The mean cost among 487 children with IBD was CA$15 168 ± 15 305. Initial treatment (anti-tumor necrosis factor therapy, aminosalicylates, or systemic steroids), having a mental health care encounter, undergoing surgery, emergency department visit at diagnosis, sex, and age were predictors of increased costs, while having a regular primary care provider was a predictor of decreased costs. The C-statistic for our model was 0.71.

Conclusions — The cost of caring for children with IBD in the first year after diagnosis is immense and can be predicted based on characteristics at diagnosis. Efforts that mitigate rising costs without compromising quality of care are needed.