The effect of COVID-19 and socioeconomic inequalities on emergency department accesses for psychiatric conditions

Background: COVID-19 produced a detrimental effect on mental health that could not be appropriately addressed due to a reduced accessibility of healthcare services, as patients with socioeconomic vulnerabilities faced the largest barriers in accessing healthcare during the pandemic. Methods: This is a multicentre longitudinal retrospective study that involves a population-based open cohort of residents and National Health Service (NHS)beneficiaries aged ≥ 10, enrolled in three large Italian areas from 1 January 2018 to 31 December 2021 (n = 5,159,363). The primary outcome of interest was the First Mental Health Emergency Access (FMHEA); sex, age, deprivation level, citizenship and groups of diagnosis were considered as covariates. Crude incidence rates were calculated comparing the two time periods (pre- and post-COVID-19) by each covariate. In the context of interrupted time series (ITS), incidence rate ratios (IRR) of FMHEAs with 95%CI were estimated via an ITS analysis using a step-change negative binomial model. Temporal trend of FMHEAs was investigated through an ITS analysis on their monthly numbers. Results: During follow-up, 56,762 FMHEAs were observed. The multivariate analysis showed that before COVID-19, the rate of FMHEA was higher among the highly deprived (IRR: 1.28; 95%CI:1.22.-1.35 for highest vs lowest deprivation level), females, people aged ≤24 and ≥85 and immigrants. A significant interaction between the COVID-19 period and deprivation level was found: the probability of reduced FMHEA increased with the deprivation level. The greater impact of COVID-19 was found in the central age classes resulting in a reduction in the differences in FMHEA rates by age in the post-Covid-19 period. Conclusion: COVID-19 reduced incidence rates of ED accesses, but increased socioeconomic inequalities in the use of ED for mental health disorders.