Unpacking the Specific Associations Between Adverse Childhood Experiences and Depressive Symptoms among the Middle-Aged and Elderly Chinese Populations: A Dimensional Approach and Latent Class Analysis in a Cohort Study.

Background: Adverse childhood experiences (ACEs) are recognized as key risk factors linked to poor mental health throughout life. However, research on the specific associations between ACE dimensions and depressive symptoms (DSs) among the Chinese population during mid to late life is rare. Objectives: This study aims to investigate the specific effects of different dimensions of ACEs on the new occurrence of DSs and the number of times with DSs among the middle-aged and elderly Chinese populations. Methods: The analysis included 3979 adults aged ≥45 years with four repeated measurements of the 10-item Center for Epidemiological Studies Depression Scale from the China Health and Retirement Longitudinal Study 2011-2018. Three types of ACE dimensions (total, deprivation, and threat-related ACEs) were conceptualized in accordance with the 15 types of ACEs that occurred before the age of 18 years recorded using the Life History Survey Questionnaire in 2014. In addition, latent class analysis (LCA) was utilized as an additional method for identifying distinct ACE clusters. The Cox regression and ordered logistic regression were used to estimate the risk of ACEs on DSs. Results: Among the 3979 participants, 1656 developed a new occurrence of DSs during follow-up, with 998, 438, and 220 exhibiting DSs one, two, and three times. For total and deprivation-related ACEs, only the group with ≥3 ACEs was significant with the new occurrence of DSs when compared with the no ACE group, and the adjusted hazard ratios (HRs) (95% confidence interval) were 1.562 (1.296, 1.882) and 1.446 (1.221, 1.712), respectively. With regard to threat-related ACEs, all three groups (1 ACE, 2 ACEs, and ≥3 ACEs) were significantly associated with the new occurrence of DSs. The HRs were 1.260 (1.115, 1.425), 1.407 (1.212, 1.634), and 1.585 (1.366, 1.840), respectively. The findings of total, deprivation-related, and threat-related ACEs and their associations with the number of times with DSs represent a similar phenomenon. The LCA revealed five ACE clusters. Compared to the "low risk" cluster, the "poor parent relationship" cluster and the "physical abuse" cluster were linked to an increased risk of the new occurrence of DSs and the number of times with DSs. The results of the subgroup analysis by sex and age were consistent with the total population. Conclusions: Individuals who have experienced higher ACE scores in early life face a higher risk of developing a new occurrence of DSs and multiple detected DSs in mid to late life, particularly in the case of threat-related ACEs. Parsing ACEs is imperative to explore their distinct effects on DSs and the underlying mechanisms. In addition, Incorporating ACE screening into regular health checks among the middle-aged and elderly populations is recommended. Moreover, targeted mental health interventions should be delivered to those who have experienced early life adversities, particularly threat-related ACEs, to promote healthy aging.