Objective: Symptoms of anxiety, depression commonly co-occur with cognitive decline in patients with Parkinson's disease (PD). The directionality of this association is unclear, however, in that poor cognitive performance may lead to increased symptoms of anxiety and depression or higher anxiety and depressive symptoms may lead to cognitive decline. The purpose of this study was to elucidate the directionality of the association between symptoms of anxiety and depression with cognitive performance in newly diagnosed patients with PD.
Method: Longitudinal data from 362 nondemented participants from the Parkinson's Progression Markers Initiative (PPMI) were examined. Participants completed as many as five assessments of anxiety symptoms, depressive symptoms, and cognitive performance over a 4-year period. Bivariate dual change score models were fit to examine the dynamic association between level and change of anxiety and depressive symptoms with level and change in cognitive performance.
Results: Across all cognitive domains, worse performance was associated with subsequently higher state anxiety, trait anxiety, and depressive symptoms. The reverse direction was not significant as higher state anxiety, trait anxiety, and depressive symptoms were not associated with subsequent declines in cognitive performance.
Conclusions: Poorer cognitive performance, across all cognitive domains, was a risk factor for increased symptoms of anxiety and depression a year later. No support was present for the alternative hypothesis that anxiety and depression are associated with subsequent cognitive decline. Clinical implications include the importance of psychoeducation, as well as assessing and monitoring anxiety and depression in patients with PD with poor cognitive performance. (PsycINFO Database Record (c) 2019 APA, all rights reserved).