The role of depression severity in the cognitive functioning of elderly subjects with central nervous system disease

Objective: To examine the hypothesis that there is a causal relation betwee n depression and cognitive dysfunction in patients with central nervous sys tem (CNS) disease. Design: Retrospective analysis of a clinical database. S etting: Tertiary geriatric day hospital. Patients: Sixty-five patients with depression and CNS disease, and 201 patients with depression but without C NS disease. Outcome measures: Scores on the Hamilton Depression Rating Scal e (Ham-D) and the Mattis Dementia Raring Scale (MDRS). Results: A logistic regression analysis using MDRS status as the dependent variable, and a numb er of clinical variables as the predictor variables, showed that, in patien ts with CNS disease, only the Ham-D score predicted MDRS status (R = -0.19, p = 0.02). Ham-D score even more strongly predicted scores on a frontal sy stem subtest of the MDRS (R = -0.262, P = 0.005). Ham-D score did not predi ct MDRS status in patients without CNS disease. Mean Mini Mental State Exam ination scores for the group with CNS disease were 25.1 at admission and 26 .1 at discharge (P < 0.001). Conclusions: These findings suggest that depre ssion contributes to frontal cognitive dysfunction in patients with CNS dis ease.