Visuoconstructional drawing ability in the differential diagnosis of neurologic compromise versus depression

Neuropsychologists are often called upon to assist in making differential diagnoses between neurologic compromise and depression. However, the literature has been inconsistent about the impact of depression on neurocognitive functioning. This makes interpretation of neuropsychological test data among depressed individuals difficult. In a retrospective cross-sectional study of 200 patients, the relationship between depression (Beck Depression Inventory or Geriatric Depression Scale) and visuoconstructional drawing ability/praxis (Rey-Osterrieth Copy [RO]) was evaluated. Age and education both correlated significantly with RO performance (p <.001 and.005, respectively). There were no significant relationships found between copy performance and depression, even when controlling for the significant effects of age and education. A prospective longitudinal study of 20 psychiatric inpatients with depression tested on admission and again at discharge matched with 20 nondepressed normal controls yielded similar results in that the two groups did not differ in their initial RO performance. Moreover, an improvement in depression as measured by a decrease in Beck Depression Inventory scores did not coincide with any improvement in RO scores. By comparison, a matched positive control group of 20 neurologically compromised patients was significantly worse than both the normal control and the depressed groups on the RO (p <.05). These data suggest that poor performance on the RO should not be interpreted simply as a consequence of depression. Age and education, though, should be considered when interpreting the RO.