Cardiff University researchers collected cognitive performance data on 199 ECT patients over a 10-year period. The main goal was to see if repeated or ongoing courses of ECT caused cumulative cognitive problems. The researchers were also interested to know if other factors such as age, days since last ECT session, and depression severity played a role in any cognitive decline.

Nine cognitive tests measuring recognition, working memory, verbal fluency, processing speed, and mental status were given at three time points: prior to the start of ECT, within 1 week after treatment completion, and at 3 months follow-up. Those who received multiple courses of ECT were tested again at the same intervals. Those who required maintenance ECT (>50 sessions) were tested yearly. The total number of ECT sessions patients received prior to the testing was also recorded.

The analysis showed that the total number of ECT sessions had no effect on performance on any of the cognitive tests given to patients. The factors that did decrease performance were greater age and more severe depression. However, a longer time gap since the last ECT session was associated with improved performance.

TCPR’s Take: Many patients are concerned about the long-term effects of ECT. While this study is not definitive, since it is not a randomized controlled study, it is highly suggestive that long-term ECT, including maintenance treatments, does not significantly impair cognition.