Abstract
BACKGROUND: This study aimed to examine the association of internal migration experience with depressive symptoms among middle-aged and elderly Chinese, as well as explore possible mechanisms of the relationship. METHODS: Participants were from the China Health and Retirement Longitudinal Study (CHARLS), a nationally representative sample of residents aged 45 years and older (n = 43,854). Survey data on depressive symptoms and internal migration experience were collected from biennial CHARLS surveys (CHARLS 2011/2013/2015) and a unique CHARLS life history survey in 2014, respectively. Multiple logistic regressions and the Karlson-Holm-Breen (KHB) method were employed in the statistical analyses. RESULTS: The overall prevalence rate of depressive symptoms among middle-aged and older adults was 34.6%. Internal migration experience was associated with higher risks of depressive symptoms (OR = 1.07, 95% CI = 1.02-1.12, p < 0.01), especially among females (OR = 1.08, 95% CI = 1.01-1.14, p < 0.05), middle-aged adults (OR = 1.12, 95% CI = 1.06-1.19, p < 0.001), rural-to-urban migrants who had not obtained an urban hukou (OR = 1.13, 95% CI = 1.07-1.19, p < 0.001), and those who had low migration frequency and first migrated out at 35 years of age or older. Chronic disease (17.98%, p < 0.001), physical injury (7.04%, p < 0.001), medical expenditure (7.98%, p < 0.001), pension insurance (4.91%, p < 0.001), and parent-child interaction (4.45%, p < 0.01) were shown to mediate the association of internal migration experience with depressive symptoms. CONCLUSIONS: This study indicates that there is a significant association between internal migration experience and high risks of depression onset later in life. It is suggested to reduce institutional barriers for migrants and implement evidence-based interventions to improve migrants' mental health.