Psychiatric inpatient services in Ontario, 2019-2021: a cross-sectional comparison of admissions, diagnoses and acuity during the COVID-19 prerestriction, restriction and postrestriction periods.

Background: The COVID-19 pandemic was associated with increased mental health problems in the general population, yet psychiatric hospital admissions decreased. Early evidence suggested that psychiatric admissions normalized within weeks; we sought to examine the longer-lasting impacts on the psychiatric inpatient population beyond this initial period.

Methods: We compared Ontario Mental Health Reporting System admission data for patients admitted to 8 psychiatric hospitals in Ontario, Canada, between 3 time periods - before restrictions were imposed (June 22, 2019, to Mar. 16, 2020), during restrictions (Mar. 17 to June 21, 2020) and after restrictions were lifted (June 22, 2020, to Mar. 16, 2021) for changes in involuntary status, diagnoses and clinical presentation using descriptive analysis. For clinical presentation, we extracted scores on 4 Resident Assessment Instrument-Mental Health symptom scales (Depressive Severity Index, Cognitive Performance Scale, Positive Symptoms Scale-Long Version and Social Withdrawal Scale), and 2 behaviour scales (Aggressive Behavior Scale and Violence Sum).

Results: A cross-sectional sample of 9848 patients was included in the analysis. The mean number of daily admissions decreased 19% from 16.4 (standard deviation [SD] 8.0) before the restriction period to 13.3 (SD 6.1) during the restriction period, and was still 6% below prerestriction levels after restrictions were lifted 15.4 (SD 6.8), with standard error difference of 1.03 (95% confidence interval -0.22 to 2.29). From the pre- to the postrestriction periods, the proportion of involuntary patients increased by 6 percentage points, and the proportions of patients diagnosed with a psychotic disorder or personality disorder increased by 4 percentage points and 1 percentage point, respectively.

Interpretation: Psychiatric admissions did not fully return to prerestriction levels in absolute rates and patient acuity after COVID-19 restrictions were lifted. Psychiatric services must prepare to appraise and respond to any increased acuity through interventions for patients, workforce planning and mental health support for staff.