Early effects of electroconvulsive therapy on cognitive function

Routine screening of cognitive function during a course of electroconvulsive therapy (ECT) is recommended in several guidelines. However, there is little evidence regarding which measures are practical, change early in treatment, and are likely to predict longer term cognitive problems. We aimed to investigate the practicality of early formal cognitive screening in routine clinical practice of ECT.

Thirty-three patients aged 25 to 84 years were recruited from 2 ECT clinics. Assessment consisted of the Rey Verbal Learning Test (RAVLT), The Short Form of the Colombia University Autobiographical Memory Interview, Digit Span Forwards and Backwards, and Modified Mini-Mental State Examination (3MSE) and was conducted at baseline, between the third and the fourth treatment of ECT and 2 months after the last treatment. Analysis examined which measures changed after 3 treatments and whether this correlated with change at the 2 month follow-up.

After 3 treatments, there was a significant reduction in immediate (F1,27 = 14; P = 0.001) and 30-minute delayed (F1,25 = 34; P < 0.001) recall of the RAVLT. There was also a significant reduction in autobiographical memory score but no significant change in digit span or 3MSE. There was no correlation between reductions in scores on the RAVLT and The Short Form of the Colombia University Autobiographical Memory Interview, after 3 treatments and reductions at 2 month follow-up.

This small pilot study suggests that significant changes in memory function can be detected as early as after 3 treatments of ECT and that such monitoring can be done in routine clinical practice. There was, however, no evidence that these changes correlated with longer term changes.