Abstract
BACKGROUND: The global prevalence of depression is on the rise, and has evolved into a major public health concern. Given that parental favouritism in childhood exerts a long-term impact on children's mental health, we aimed to explore its association depression in old age. METHODS: We retrieved 19 180 data points from 3836 individuals aged 60 years and over from the China Health and Retirement Longitudinal Study 2011, 2013, 2015, 2018, and 2020 waves, among whom depression was measured using the Centre for Epidemiological Studies Depression Scale. We used logistic analysis to determine the relationship between parental favouritism in childhood and depression in old age, and the bootstrap method to analyse the mediating role of smoking, drinking, socialising, exercising, and sleep duration. RESULTS: Approximately 17% of older adults experienced parental favouritism during childhood. We found that parental favouritism significantly increased the probability of depression by 29.9% (β = 0.299; 95% confidence interval (CI) = 0.145, 0.453), as did mother's favouritism by 28.4% (β = 0.284; 95% CI = 0.117, 0.450), and father's favouritism by 23.6% (β = 0.236; 95% CI = 0.058, 0.415). Socialising (β = -0.0018; 95% CI = -0.0028, -0.0009), exercising (β = 0.0009; 95% CI = 0.0003, 0.0017), and sleep duration (β = 0.0046; 95% CI = 0.0015, 0.0076) mediated this relationship. An analysis of heterogeneity by gender found that women are more influenced by parental favouritism. CONCLUSIONS: Parental favouritism in childhood significantly predicts the probability of depression in old age. Promoting socialising, exercising, and sleep duration could help to alleviate this issue. We also noted that women are more influenced by parental favouritism. These findings provide guidance for targeted interventions, such as mental health screening and promotion of healthy lifestyles.