Mental healthcare use among children and adolescents with high healthcare costs in Ontario, Canada

Importance — Research on patients with high healthcare costs has examined mainly adults, with little focus on mental healthcare use.

Objective — To examine the characteristics and costs of children and adolescents with high healthcare costs who use mostly mental healthcare and whether and why they persist in the high-cost state.

Design, Setting, and Participants — This population-based, retrospective cohort study used healthcare records from Ontario, Canada, on all children and adolescents (age 0-17 years) covered under a universal healthcare system from January 1, 2012, to December 31, 2019. All children and adolescents in and above the 90th percentile of the cost distribution in 2012 for whom costs related to mental healthcare accounted for 50% or more of their costs were defined as patients with high mental healthcare costs. Data were analyzed from August 2019 to December 2022.

Exposures — High healthcare costs.

Main Outcomes and Measures — Patients with high mental healthcare costs were characterized in terms of their sociodemographic characteristics; chronic physical health, mental health, and behavioral conditions; and healthcare costs (in 2021 Canadian dollars) by health service and type of care (mental healthcare vs non–mental healthcare). Patients were followed up until 2019 to assess whether they persisted in the high-cost state and to examine factors associated with persisting in that state.

Results — In 2012, there were 273 490 children and adolescents with high healthcare costs (mean [SD] age, 6.43 [5.99] years; 55.8% male; mean cost, $7936.40; 95% CI, $7850.30-$8022.40). Of these, 20 463 (7.5%) were classified as having high mental healthcare costs (mean cost, $10 040.20; 95% CI, $9822.80-$10 257.50). Asthma (30.3%), attention-deficit/hyperactivity disorder (35.8%), and mood and/or anxiety disorders (94.9%) were the most common chronic physical, behavioral, or mental health conditions. Few patients with high mental healthcare costs persisted in the high-cost state beyond 3 years (19.0%). Mood and/or anxiety disorders (relative risk ratio [RRR], 6.17; 95% CI, 3.19-11.96) and schizophrenia spectrum disorders (RRR, 2.98; 95% CI, 2.14-4.14) were identified as the main factors associated with persistence in the high-cost state.

Conclusions and Relevance — In this cohort study of children and adolescents with high healthcare costs, some patients had high levels of mental healthcare use and high costs of care, but few of these persisted in the high-cost state for 3 or more years. These findings may help inform the development of care coordination interventions and service delivery models, such as youth integrated services, to reduce costs and improve outcomes for children and adolescents.