Background: The CoVID pandemic and the associated lockdown had a significant impact on mental health services. Inpatient services faced the challenge of offering acute psychiatric while implementing strict infection control measures. There is, however, a lack of studies investigating the use of coercive measures during the pandemic and their relation to hospitalizations and symptom severity.

Aims: To investigate the effects of the CoVID outbreak on psychiatric admissions, use of seclusion and symptom severity.

Method: Using routine data from 2019 and 2020 gathered in the Department of Psychiatry at the Geneva University Hospitals, we performed an interrupted time series analysis. This included the number of psychiatric hospitalizations, the proportion of people who experienced seclusion and the average severity of symptoms as measured by the Health of Nations Outcome Scale (HoNOS). Dependent variables were regressed on the time variable using regression model with bootstrapped standard errors.

Results: Hospitalizations decreased over time ( b = -0.57, 95% CI: -0.67; -0.48, p < .001). A structural break in the data (supremum Wald test: p < .001) was observed in the 12 ^th week of 2020. There was an inverse relationship between the number of admissions and the proportions of people subject to seclusion ( b = 0.21, 95% CI: -0.32; -0.09, p < .001). There was a statistically marginally significant inverse relationship between HoNOS scores at admission and the number of psychiatric hospitalizations ( b = -1.28, 95% CI: -2.59, 0.02, p = .054).

Conclusion: Our results show that the CoVID pandemic in 2020 was associated with a significant decrease in the number of hospital admissions. This decrease was correlated with a greater use of seclusion. The higher burden of symptoms and the difficult implementation of infection control measures might explain this higher use of coercion.