SARS-CoV-2 pandemic waves and Mental Health management: an Interrupted Time Series analysis in Northern Italy.

Background and aim: The coronavirus disease (COVID-19) outbreak, caused by the SARS-CoV-2, represents one of the most important public health threat in the last few decades. The rapid spread of the virus and the increasing number of COVID-19 cases worldwide imposed measures such lockdowns to reduce its transmission. The characteristics of this catastrophic event, together with the lockdown measures and societal changes, have had impacted on the population’s mental health. For this reason, this study aimed at assessing the impact of COVID-19 pandemic waves on mental health services utilization in one of the most heavily affected Italian regions, the province of Bergamo. Specifically, the study aimed at assessing the impact of the first and second lockdowns on emergency department access and hospitalization due to psychiatric diseases, the new use of psychiatric therapies, and access to mental health services in the general population. Methods: A population-based study using the healthcare administrative database of the Health Protection Agency (HPA) of Bergamo was conducted. Weekly time series data on emergency department access/Hospitalization due to psychiatric diseases, along with the new use of antidepressants/antipsychotics, and outpatient mental health service utilization from January 1, 2017 to December 31, 2022 were collected. The study period was segmented as follows: pre-first lockdown period (January 1, 2017 - March 7, 2020), first lockdown (March 8, 2020 - June 1, 2020), post-first lockdown (June 2, 2020 - November 5, 2020), second lockdown (November 6, 2020 - June 27, 2021), and post-second lockdown (June 28, 2021-o December 31, 2022). Frequency measures across these periods were compared using nonparametric tests and relative changes in mean values. Then, an interrupted time series (ITS) analysis with Poisson generalized additive model was used to assess significant changes (p-value ≤0.05) in either the level (meaning an abrupt change) or the slope (meaning a gradual change) of the time series for study events. Results were reported as point estimates with corresponding 95% Confidence Intervals (95%CI). The impact of lockdowns was estimated across different age groups (adult and young) and sex (female and male). Results: The first lockdown was associated with a significant reduction in the incidence of the study events across the different study subgroup populations. The post-first lockdown was associated with an increase of the study event. The second lockdown was associated with a new reduction of the study events followed by an increase in occurrence during the post-second lockdown. A distinct pattern was observed for the use psychiatric drugs use among younger individuals, which showed an increasing trend following the first lockdown. Analyses stratified by sex among adults showed similar pattern for both males and females. Conclusion: The findings reveal the impact of the COVID-19 pandemic on the mental health of the general population, indicating a deterioration in well-being during each lockdown, followed by a rebound effect in the post-lockdown periods. Given the differential impact of pandemic on adult and young individuals, there is a need for targeted public health interventions to address the mental health needs of these distinct groups. Future studies should explore the long-term effects of the pandemic on additional subpopulations to identify potential areas of need for mental health support.