The Protective Role of Childhood Friendship on the Effects of Parental Depressive Symptoms and Adult Depressive Symptoms among People with Cardiovascular Disease

Introduction: Individuals whose parents had depressive symptoms in childhood are more likely to develop depressive symptoms in adulthood than the general population. Few studies have explored the association between the above two in patients with cardiovascular disease(CVD). In addition, it is not clear whether childhood friendship plays an intermediary role between childhood parents' depressive symptoms and adult depressive symptoms. Methods In our study, we selected people suffering from CVD who participated in the China Health and Retirement Longitudinal Study (CHARLS) life history survey and 2018 wave of CHARLS national baseline survey. We made statistical analysis on the assumption that childhood friendship was the mediator between childhood parental depression and adult depressive symptoms. Multi-level logistic regression analysis and Sobel Goodman mediation test were used to measure the association between childhood parental depression, childhood friendship and adult depressive symptoms. Results A total of 5565 participants were included in our study. The proportion of people with CVD having significant depressive symptoms accounted for 43.94%, which was higher than that of total population in the same period(36.62%, p <0.05). The results of logistic regression analysis showed that childhood parental depressive symptoms increased the risk of adult depressive symptoms(Model 3, OR : 1.621, 95% CI : 1.387–1.895). In contrast, childhood friendship was a protective factor for adult depressive symptoms (Model 3, OR : 0.788, 95%CI: 0.685–0.906), and played an intermediary role between childhood parental depressive symptoms and adult depressive symptoms. Through the Sobel-Goodman test, we found that the mediating effect of childhood friendship between the other two accounted for 6.14% of the total effect ( p  < 0.001). Conclusions In middle-aged and elderly Chinese with CVD, childhood friendship is a protective factor of adult depressive symptoms, and it is the mediator between childhood parental depression and adult depressive symptoms.