Effects of anxiety versus depression on cognition in later life

Objective: The authors investigated the relationship between anxiety and cognition in older persons, taking account of comorbid depression. Methods: Data were used from the Longitudinal Aging Study Amsterdam (LASA), a large epidemiological study of 3,107 elderly citizens in The Netherlands. Anxiety and depression were measured with the Hospital Anxiety and Depression Scale-Anxiety subscale and the Center for Epidemiologic Studies-Depression Scale. In measuring cognitive performance, general cognitive functioning was measured by means of Mini-Mental State Exam, episodic memory was measured with the Auditory Verbal Learning Test (AVLT), fluid intelligence by using the RAVEN, and information-processing speed by the coding task. Analysis of variance examined the association between anxiety symptoms and cognition in persons with and without depression. Results: Main effects of anxiety symptoms were found for learning and delayed recall of the AVLT. Depression symptoms showed significant main effects on almost all cognitive performance tests. Mild anxiety symptoms were associated with better cognitive performance, whereas severe anxiety symptoms were negatively associated with cognitive functioning. In contrast, depressive symptoms showed a linear association with cognition; more depression was associated with worse cognition. Conclusion: This study suggests that anxiety has a curvilinear relationship with cognition. Depressive symptoms, however, were always negatively associated with cognitive performance.