Effects of pharmacological therapy on gait and cognitive function in depressed patients

Objective: To investigate the relationship among affective status, cognitive function, and gait in depressed patients and to evaluate the effects of treatment of depression on gait and cognitive function. Methods: Nineteen patients recently diagnosed with clinical depression (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria) were recruited from a psychiatric outpatient clinic. Evaluation included the Hamilton Depression Rating Scale (HAM-D), the Mini-Mental State Examination, a computerized neuropsychological battery (Mindstreams, NeuroTrax Corp, New York, NY), and Barthel's Index of Instrumental Activities of Daily Living. Temporal parameters of gait were quantified using a stopwatch and force-sensitive insoles. All assessments were performed at baseline and after approximately 10 weeks of treatment with antidepressants. Results: The patients' mean age was 68.6 +/- 9.1 years (15 women). Therapy significantly (P < 0.001) improved the affective state (HAM-D scores). There were small but significant improvements in gait speed (P = 0.033), stride time variability (P = 0.036), and gait asymmetry (P = 0.038). With the exception of the hand-eye coordination index, all tested cognitive domains also improved significantly. Baseline depression scores correlated with changes in depression: patients with higher HAM-D scores at baseline had more significant improvement in their affect (P < 0.001). Changes in HAM-D were not significantly correlated with changes in gait or changes on computerized tests of cognitive function (P > 0.10). Conclusions: Depressive symptoms are associated with gait and cognitive impairment. Moreover, the present results suggest that these domains improve in response to antidepressant medication.