Follow-up timing after discharge and suicide risk among patients hospitalized with psychiatric illness

Importance  Although early outpatient follow-up after psychiatric inpatient discharge may prevent suicide, the association between early follow-up care and a reduced risk of suicide after discharge has not been fully explored. Objectives  To investigate outpatient follow-up care after psychiatric inpatient discharge and determine whether the timing of the first outpatient follow-up is associated with a reduced risk of suicide. Design, Setting, and Participants  This population-based, retrospective cohort study used the National Health Claim Database from 2017 to 2018 in Korea. Patients were observed until December 31, 2021, to confirm the occurrence of suicide. The study population included all patients aged 18 years or older who were newly admitted to hospitals with psychiatric illness except for dementia from January 1, 2017, to December 31, 2018. Statistical analysis was performed from January to May 2023. Exposure  The timing of the first mental health outpatient care follow-up within 30 days after discharge. Main Outcomes and Measures  The outcome of interest was suicide after hospital discharge. The timing of the first follow-up visit was observed within 30 days after discharge. The Cox proportional hazard model was used to explore the association between the risk of suicide and the timing of outpatient follow-up. Results  Of the 76 462 patients admitted to hospitals from 2017 to 2018, 225 (52.6%) were male; 21 313 (27.9%) had a primary diagnosis of substance use disorder, 17 608 (23.0%) had schizophrenia, and 15 018 (19.6) had depression; mean (SD) age was 46.4 (16.3) years. A total of 49 319 patients (64.5%) received follow-up outpatient care within 30 days of discharge. The mean (SD) follow-up period was 30.8 (20.2) months, and 1536 patients died of suicide during the study period. The hazard ratio for suicide risk in patients who received outpatient care within 7 days compared with those who did not receive any care within 30 days after discharge was 0.82 (95% CI, 0.80–0.83). The earlier the time of outpatient follow-up care, the lower the risk of suicide for those with substance use disorder, schizophrenia, bipolar disorder, and depression. Conclusions and Relevance  In this cohort study of patients with psychiatric illness, early follow-up outpatient care after discharge was associated with a lower risk of suicide. These results suggest that those at high risk of suicide during hospitalization need intensive follow-up immediately after discharge.