The impact of regional Internet development on Chinese middle-aged and older adults' depression, 2011-2018

Background and Objectives: This study investigates the impact of regional Internet development on depression among middle-aged and older Chinese individuals aged 45 and above from 2011 to 2018, an ecological factor rarely examined in health policy regarding mental health. We explore this association using China Health and Retirement Longitudinal Study data. Research Design and Methods: We employed Lagged dependent variable approach and Generalized Estimating Equations to analyze the association between regional Internet development and depression in this demographic. Subgroup analysis was used for heterogeneity effect analysis, and cross-level interaction analysis between regional Internet development and gender was conducted to test gender role moderation. Results: Chinese middle-aged and older adults residing in provinces with higher Internet development levels have fewer depression symptoms. Both male and female Han Chinese benefit from higher provincial Internet development, while ethnic minority males and females do not. As provincial Internet development increases, the negative effect on depression symptoms weakens for Han males but strengthens for Han females, indicating a partial reduction in the depression gap between them. Discussion and Implications: This study is the first to investigate the relationship between regional Internet development and mental health in middle-aged and older adults aged 45 and above. Policymakers should address Internet development disparities across regions to prevent further health consequences and reduce the digital divide. The heterogeneity effect of regional Internet development should also be considered.