Covid-19 and mental health hospitalizations in Italy. Results from a multicenter longitudinal cohort

Abstract Background The impact of Covid-19 pandemic on mental health (MH) is still being assessed. The aim of this study was to evaluate the impact of Covid-19 on ordinary hospital admissions for psychiatric disorders in Italy. Methods The multicenter project “Covid-19 and mental health” (CoMeH), coordinated by the National Institute for Health, Migration and Poverty, enrolled an open cohort of subjects resident in three large areas of Italy (2018-2021) aged 10 + (N = 5,159,363), and followed-up until 2021. The study outcome was the first ordinary admission with a psychiatric disorder as main diagnosis (FMHA). Citizenship and deprivation level (DL) are the socioeconomic factor considered. Different groups of diagnosis were used to characterize the hospitalizations. The impact of Covid-19 on FMHAs was evaluated by interrupted time series (ITS) analysis, pre (until February 2020) and post (from March 2020) the outbreak of pandemic, using a step-change model. Results 11,171 FMHAs were observed. Patients hospitalized with a MH diagnosis were younger compared to the study population; the distributions by sex, deprivation level and citizenship were similar. A decrease of incidence of FMHAs was found after the outbreak of the pandemic, overall and for all group of diagnoses, except for post-traumatic stress disorders (PTSD). A reduction in adjusted FMHA rates after the onset of Covid-19 (RR 0.80[0.72-0.90]) were observed through multivariate ITS. The oldest patients had the lowest probabilities of FMHAs in pre Covid-19 and experienced the highest reduction in post-Covid19. PTSD presented trend in countertendency compared with the other diagnosis, with an immediate effect of Covid-19 increasing FMHAs (+97%), followed by a post-outbreak return to the pre-pandemic levels, below the counterfactual line. Conclusions Covid-19 pandemic determined a general reduction of admissions for psychiatric disorders. A significant impact was observed among the eldest (decrease) and for PTSD (increase). Key messages • Covid-19 pandemic determined a reduction of admissions for psychiatric disorders. • Older people were mostly affected. No significant socioeconomic impact was observed.