Usefulness of the Montreal Cognitive Assessment (MoCA) to monitor cognitive impairments in depressed patients receiving electroconvulsive therapy

There is a lack of consensual tools for evaluating the cognitive side-effects in patients with depression who are treated with electroconvulsive therapy (ECT). The objective of this study was to evaluate the usefulness of the Montreal Cognitive Assessment (MoCA) and of the Mini Mental State Examination (MMSE) to monitor cognitive changes in patients with depression receiving ECT. Cognitive functioning was assessed prospectively in 48 patients with unipolar or bipolar depression before and after an ECT course. ECT-induced cognitive impairments were defined as a decrease of at least 2 points on the MoCA and the MMSE total scores and of at least one point on each sub-score. At baseline, the MoCA detected a higher number of patients with cognitive deficits than the MMSE. After ECT, the MoCA and MMSE total scores were comparable, but the MoCA detected more impairments than did the MMSE for visuo-executive, memory and language subscores. ECT significantly decreased the language capacities but improved the visuo-executive and abstraction performances measured by MoCA. In remitters, the MoCA total score and visuo-executive and abstraction performances were significantly improved, while other cognitive functions remained unchanged. The MoCA is a useful screening tool for monitoring cognitive functioning during an ECT course.