Abstract
BACKGROUND: The prevalence of depressive symptoms increased significantly in the early stages of the COVID-19 pandemic and remained elevated even as lockdown policies were eased. Therefore, a thorough evaluation of the pandemic's long-term effects on depressive disorders is critical. METHODS: A repeated cross-sectional study was conducted using data from the National Health Interview Survey collected before (2017-2018) and during the later stage of the COVID-19 pandemic (August 2021-August 2023). χ(2) tests were conducted to compare the characteristics between nondepressed and depressed adults. Weighted multivariable logistic regression models were employed to estimate the associations between social and physical factors with depressive symptoms. RESULTS: The prevalence of depressive symptoms in the later stages of the COVID-19 pandemic (12.7%) was significantly higher than prepandemic levels (9.1%). Specifically, the incidence rates for mild, moderate, moderately severe, and severe depressive symptoms increased by 1.24-fold, 1.44-fold, 1.38-fold, and 1.71-fold, respectively, compared to prepandemic levels. Higher risk of developing depressive disorders persisted among those who were widowed/divorced/separated, never married, and with lower education or income. Prepandemic protective factors such as lower systemic inflammatory response index, no smoking or drinking, and no hypertension history became less effective. Males and females aged 20-40 exhibited the highest probability of developing depressive symptoms in the later stage of the pandemic. LIMITATIONS: The cross-sectional design prevents inference of causality. CONCLUSIONS: The persistence of mental health disparities highlights the need for sustained efforts from the government, mental healthcare organizations, and healthcare providers to support vulnerable groups even beyond the pandemic.