Parental depressive symptoms link family income to preschool child mental health in Western China.

Background: Child mental health represents a global public health priority. However, evidence regarding the association between family income and mental health among preschool children in Western China remains limited, and the potential indirect role of parental depressive symptoms has not been fully examined. Methods: This cross-sectional study included 21,366 preschool children (aged 3-6 years) and their parents in Western China. Family income was classified into low, middle, and high groups. Child mental health outcomes (total difficulties and prosocial behavior) were assessed using the Strengths and Difficulties Questionnaire (SDQ), and parental depressive symptoms were measured via the Center for Epidemiological Studies Depression Scale (CES-D). Multivariable logistic regression and mediation analyses were performed, adjusting for relevant covariates. Results: Higher family income was significantly associated with a reduced risk of child mental health problems and increased prosocial behaviors. Compared with low-income families, middle- and high-income families had 27 and 39% lower odds of total difficulties, and 9 and 30% higher odds of prosocial behavior, respectively. Parental depressive symptoms accounted for 30.5 and 44.3% of the associations with total difficulties, and 57.2 and 43.8% of the associations with prosocial behavior, in middle- and high-income groups, respectively. Conclusion: Family income is associated with preschool mental health in Western China, with parental depressive symptoms playing a substantial indirect role. These findings provide population-level evidence for understanding early childhood mental health in understudied regions of China.