Longitudinal associations between negative life events and depressive symptoms—A 9-year longitudinal study on between-person and within-person effects and the role of family history.

Research has shown that negative life events contribute to the development of depression. Moreover, it has been suggested that individuals with a family history of depression experience more negative life events and are more susceptible to the effect of negative life events. However, previous studies did not differentiate stable between-person effects (interindividual differences) and temporal within-person effects (intraindividual differences). This study aims to examine the bidirectional relation between negative life events and depressive symptoms using a novel statistical method (i.e., a random intercept cross-lagged panel model) that allows to separate within-person from between-person processes. Second, we examined the role of family history in that relation. Data came from 1,771 adults (1,320 with a depressive and/or anxiety disorder, 451 controls) that were followed over 9 years (baseline, 2-, 4-, 6-, and 9-year follow-up). Questionnaires were used to measure depressive symptoms and the number of independent (i.e., events independent of someone's symptoms) and dependent negative life events (i.e., events more likely to be influenced by a person). Results showed that individuals with more negative life events experienced more depressive symptoms on a between-person level. Additionally, although the effects were considerably smaller, results suggested within-person increases in dependent and independent negative life events were correlated with within-person increases in depressive symptoms. Overall, our results suggest that negative life events and depressive symptoms are more consistently associated on a between-person than on a within-person level. Thus, negative life events may rather explain differences in depressive symptoms between persons than within persons. (PsycInfo Database Record (c) 2021 APA, all rights reserved).