Apathy and Depression as Predictors of Activities of Daily Living Following Stroke and Traumatic Brain Injuries in Adults: A Meta-Analysis.

Apathy and depression are common sequelae of acquired brain injury (ABI). Apathy is a syndrome characterized by diminished motivation and purposeful behaviours. Depression is a mood disorder featuring sadness, worthlessness, anhedonia and suicidal ideation. Both are associated negatively with activities of daily living (ADL), the skills required to fulfil basic and complex physical needs. However, the current literature's results are inconsistent and based on relatively small sample sizes. Furthermore, the unique and combined effects of apathy and depression as predictors of ADL have not yet been estimated. This is important, as both may have implications for planning rehabilitation after an ABI. Consequently, we aimed to estimate the association between apathy, depression and ADL in the stroke and traumatic brain injured population via meta-analysis and meta-analytic path-analysis. Based on the meta-analyses (N = 1,166 to N = 1,389), we estimated the following statistically significant bivariate effects: depression and apathy (r = .53, 95% CI: .42/.63), depression and ADL (r = -.27, 95% CI: -.43/-.11), apathy and ADL (r = -.41, 95% CI: -.51/-.31). A meta-analytic mediation model found that depression had a significant indirect effect onto ADL (β = -.17, 95% CI: -.26/-.09), while apathy had a significant direct effect (β = -.34, 95% CI: -.48/-.19) onto ADL (model R2 = .16). We interpreted the results to suggest that apathy and depression may impact adversely on engagement with ADL in people with ABI, although the potential influence of depression on ADL may occur primarily through its influence on apathy. Thus, greater focus on apathy by practitioners may be merited in cases with ABI.