Health care utilization and costs following Kawasaki disease.

Objectives: Kawasaki disease (KD) is a common childhood vasculitis with increasing incidence in Canada. Acute KD hospitalizations are associated with high health care costs. However, there is minimal health care utilization data following initial hospitalization. Our objective was to determine rates of health care utilization and costs following KD diagnosis. Methods: We used population-based health administrative databases to identify all children (0 to 18 years) hospitalized for KD in Ontario between 1995 and 2018. Each case was matched to 100 nonexposed comparators by age, sex, and index year. Follow-up continued until death or March 2019. Our primary outcomes were rates of hospitalization, emergency department (ED), and outpatient physician visits. Our secondary outcomes were sector-specific and total health care costs. Results: We compared 4,597 KD cases to 459,700 matched comparators. KD cases had higher rates of hospitalization (adjusted rate ratio 2.07, 95%CI 2.00 to 2.15), outpatient visits (1.30, 95%CI 1.28 to 1.33), and ED visits (1.22, 95%CI 1.18 to 1.26) throughout follow-up. Within 1 year post-discharge, 717 (15.6%) KD cases were re-hospitalized, 4,587 (99.8%) had ≥1 outpatient physician visit and 1,695 (45.5%) had ≥1 ED visit. KD cases had higher composite health care costs post-discharge (e.g., median cost within 1 year: $2466 CAD [KD cases] versus $234 [comparators]). Total health care costs for KD cases, respectively, were $13.9 million within 1 year post-discharge and $54.8 million throughout follow-up (versus $2.2 million and $23.9 million for an equivalent number of comparators). Conclusions: Following diagnosis, KD cases had higher rates of health care utilization and costs versus nonexposed children. The rising incidence and costs associated with KD could place a significant burden on health care systems.