Bidirectional longitudinal associations between depressive symptoms and somatic conditions after adverse childhood experiences in middle-aged and older Chinese: A causal mediation analysis

Background: Whether adverse childhood experiences (ACEs) preferentially induce depressive symptoms or somatic conditions remains to be explored.

Methods: Data were from the China Health and Retirement Longitudinal Study (CHARLS) 2011-2018. Fourteen ACEs were retrospectively reported and divided into 0, 1, 2, 3, and 4 or more. Depressive symptoms were assessed using the 10-item Center for Epidemiological Studies Depression (CESD-10) scale. Somatic conditions were assessed by pain, falls, chronic diseases, multimorbidity, activities of daily living (ADL), and instrumental activities of daily living (IADL). Weibull regression and mediation analysis were used to explore the bidirectional associations between depressive symptoms and somatic conditions after ACEs.

Results: 4 or more (vs. 0) ACEs were associated with new-onset pain, falls, chronic diseases, multimorbidity, ADL limitations, and IADL limitations, with HRs (95% CIs) of 1.57 (1.37-1.79), 1.84 (1.55-2.18), 1.43 (1.19-1.72), 1.55 (1.32-1.83), 1.85 (1.54-2.23), and 1.46 (1.24-1.71), all of which were mediated by depressive symptoms by 12.3%, 8.6%, 9.6%, 11.9%, 15.3%, and 22.5%, respectively. 4 or more (vs. 0) ACEs were also associated with about 1.90-time higher risk of new-onset depressive symptoms. However, only pain, chronic diseases, and multimorbidity mediated the association by 4.1%, 3.3%, and 2.2%. All the above associations were more pronounced in women than men.

Conclusion: ACEs tend to induce depressive symptoms before somatic conditions assessed by pain, falls, chronic diseases, multimorbidity, and functional limitations rather than vice versa. Future strategies should focus first on mental health in older Chinese to lessen the burden attributed to ACEs to the greatest extent.