Background Adverse childhood experiences (ACEs) have profound lifelong impacts on health outcomes. However, less is known about their influence in late-life outcomes, such as mental health in older ages. Moreover, associations of ACEs with distinct patterns of age-trajectories of depressive symptoms and how they differ in different countries remain unclear. In this study, we investigated associations between ACEs and trajectories of depressive symptoms at mid-to-older ages in two distinct populations.

Methods We used the longitudinal data from the English Longitudinal Study of Ageing (ELSA: n=19602, ≥50y) and the China Health and Retirement Longitudinal Study (CHARLS: n=19561, ≥45y). Depressive symptoms were measured by CES-D8 (Center for Epidemiologic Studies Depression Scale) at 10 waves (2002-2022) in ELSA and CES-D10 at 5 waves (2011-2020) in CHARLS. ACEs, including child maltreatment (e.g. abuse and neglect) and household dysfunction (e.g. domestic violence, parental mental problems and bedridden parents), were retrospectively reported in both studies. Group-based trajectory modelling was used to identify distinct age-trajectories of depressive symptoms and multinomial regression was applied for analyzing the associations between ACEs and trajectories of depressive symptoms.

Results We identified three trajectory groups in both studies: in ELSA: persistent high (men: 12.3%; women: 14.7%), moderate (men: 46.6%; women: 47.9%) and low (men: 41.1%; women: 37.4%), and in CHARLS: persistent high (men: 9.3%; women: 13.2%), moderate (men: 34.1%; women: 39.4%) and low (men: 56.6%; women: 47.4%). Most ACE measures were associated with increased risk of having moderate/persistent high trajectories of depressive symptoms (mid-to-older ages) after adjusting for other ACEs, sex and childhood socioeconomic disadvantages (financial hardship, parental education, and father’s occupation). For example, for physical abuse, the adjusted relative risk ratio (RRR_adj) for high and moderate trajectories of depressive symptoms was 2.34 (95% CI: 2.21, 2.46) and 1.22 (1.18, 1.27) respectively in ELSA. It was 1.34 (1.23, 1.44) and 1.21 (1.12, 1.30) in CHARLS. For domestic violence, the respective RRR_adj was 1.84 (1.60, 2.12) and 1.45 (1.23, 1.71) for high and moderate trajectories of depressive symptoms in ELSA, and 1.32 (1.22, 1.44) and 1.26 (1.16, 1.36) in CHARLS.

Conclusion ACEs have a life-long effect on mental health of adults from mid-to-older ages in both countries, independent of childhood socioeconomic disadvantages, highlighting the need of early intervention to improve mental health in later life.