Resilience following bereavement: a longitudinal network analysis of depressive symptoms and cognitive functions in older adults
M. SemkovskaIntroduction
A well-established depression risk factor, bereavement is a major stressful life event (SLE), whose prevalence increases as people age. Depression in later life can signal dementia, while cognitive deficits increase vulnerability to depression. However, how SLEs – particularly bereavement – intervene in the reciprocal relationship between symptoms and cognitive function to trigger clinical depression remains unclear. Clarifying this mechanism is critical, given population aging and the related increase in dementia, for which depression remains a significant predictor. According to network theory, depressive symptoms and related risk or protective factors (e.g. cognitive functioning, SLEs) form an interconnected system in which the strength of associations among components reveals each factor’s specific role in activating the broader network.
Objectives
Network modelling can clarify how interactions between individual depressive symptoms and cognitive functions change over time in bereaved older adults, helping to explain why some show resilience following the loss of a loved one while others develop depression.
Methods
Contemporaneous and cross-lagged panel networks examined cross-sectional and longitudinal associations between depressive symptoms and cognitive functions in 1992 recently bereaved Danish adults aged over 70. Inclusion criteria were to have: (1) recently lost a close relative or a friend, (2) never been depressed before the bereavement occurrence, and (3) complete depressive symptom and cognitive function data at both baseline and a two-year follow-up. The networks of individuals who became depressed at the follow up (n=222) were compared to those who remained resilient to depression (n=1770).
Results
Over the two-year post-bereavement, the resilient networks showed significant structural changes between baseline and follow-up, whereas the depression-onset group maintained a stable network (Figure 1). Significant, between-group differences were observed in the predictions linking depressive symptoms and cognitive functions across time. The resilient group showed few longitudinal predictions. In the depression-onset group, baseline auditory attention, working memory, verbal learning, and delayed recall predicted follow-up depressive symptoms, while follow-up verbal fluency was predicted by baseline depressive symptoms.
Image 1: Long description.