Impact of the mental health law revision restricting hospitalization on healthcare utilization in South Korea using interrupted time series analysis.

To reduce long hospitalization durations and the high rate of compulsory psychiatric hospitalization in Korea, a revision of the Mental Health Welfare law was passed and implemented in 2017. This study quantitatively analyzed changes in hospitalization use behavior of patients with psychotic and mood disorders after revision of the Mental Health Welfare law in South Korea. The intervention time was June 2017. Data from the National Health Insurance claims were used. Participants were all patients with hospital visits involving psychotic disorders and mood disorders. We used the interrupted time-series method with segmented regression. In patients with psychotic disorders, admission decreased after the law revision. The average inpatient length of hospitalization decreased immediately after the revision, leading to a long-term decrease. Emergency room visits increased following the revision, and admission through the emergency room also increased. In patients with mood disorders, admission decreased both immediately and over the long-term after the revision. Additionally, the average inpatient length of hospitalization decreased immediately, with no significant change observed in the long term. Emergency room visits increased following the revision. Following the law revision, patients with psychiatric disorders showed a decrease in hospital admissions and length of hospital stay. However, an increasing trend in emergency room visits was identified, suggesting an increase in crisis situations. These findings indicate the need to reduce admissions and length of hospitalization while also protecting the rights of patients with psychiatric disorders. System improvements are thus necessary to prevent an increase in crisis situations and ensure appropriate treatment.