Abstract
OBJECTIVE: Anxiety superimposed on late life depression (LLD) results in greater changes to prefrontal and medial temporal brain regions compared to depression alone. Yet, the combined impact of anxiety and depression on cognition in LLD has not been thoroughly investigated. The current study investigated whether annual changes in state and trait anxiety were associated with cognitive changes in older adults with major depression. We hypothesized that the presence of anxiety among older depressed adults would be associated with worse cognitive performance in the domains of memory and executive functioning over time. DESIGN: Three-year longitudinal observational study of older adults with LLD who were offered antidepressant treatment. SETTING: Academic Health Center. METHODS: Participants included 124 adults aged 60+ who met criteria for major depression at baseline. The association between anxiety and cognition was examined with separate multilevel linear models that addressed both between-subject and within-person effects of state and trait anxiety on cognitive functioning tests. RESULTS: Individuals who experienced annual increases in anxiety above his/her personal average also experienced cognitive decline. Increases in state anxiety were associated with declines in memory and global cognition. By contrast, increases in trait anxiety were associated with declines in mental flexibility and memory. These findings remained significant even when controlling for changes in depression over time. CONCLUSION: In LLD, individual increases in state and trait anxiety were associated with cognitive declines in different domains.