Abstract
BACKGROUND: The COVID-19 pandemic has significantly affected global health, leading to an increased incidence of mental health disorders, particularly depression. METHODS: This matched cohort study aimed to assess the impact of COVID-19 on antidepressant prescriptions using data from Japan's National Insurance Claims Database. The primary outcome was new antidepressant prescriptions, with SARS-CoV-2 infection as exposure. Data were matched by age, sex, Charlson comorbidity index (CCI), and insurance enrollment date to compare SARS-CoV-2 infected individuals with matched uninfected controls. Follow-up was terminated upon new antidepressant prescriptions or at the end of the study. The incidence rate ratios (IRR) and differences were calculated and compared using survival analysis. RESULTS: In this study, 16 million participants were analyzed, forming approximately 2.5 million pairs. Over 34 months (median follow-up: 7 months, interquartile range 4-13), there were 54,352 and 33,101 antidepressant prescriptions in the COVID-19 and control groups, respectively, with a cumulative incidence difference of 841 events (95% confidence interval [CI]: 815-860) per 1,000,000 person-months and an IRR of 1.56 (95%CI 1.54-1.58). The largest increase was observed with serotonin antagonists and reuptake inhibitors (IRR:2.18, 95%CI 2.11-2.25). Subgroup analyses revealed higher prescription rates among older adults (65 + years; IRR:2.02, 95%CI 1.98-2.07) and those with higher CCI scores (4+; IRR:1.82, 95%CI 1.77-1.88). Sensitivity analysis confirmed a persistent increase in risk 1-year post-exposure, with IRR of 1.65 (95%CI 1.63-1.68) and 1.23 (95%CI 1.19-1.27) before and after 1 year, respectively. CONCLUSION: COVID-19 is significantly associated with an increased risk of antidepressant prescriptions, underscoring the need for enhanced mental health support and resources. Addressing stigma and ensuring timely interventions are essential for managing mental health in this context.