"Cognitive impairment" after ECT treatment for depression

Wednesday, February 19, 2003
By Nick Lamb

Spanish scientists have discovered that depressive patients appear to suffer cognitive dysfunction during maintenance treatment with electroconvulsive therapy (M-ECT).

A small study published in the journal Psychological Medicine found that depressed patients receiving this treatment experienced impairments in both short-term memory and frontal function.

Although previous studies have shown that acute courses of ECT can lead to adverse physical effects, this is the first report of cognitive side effects, the researchers said.

Dr L Rami-Gonz·lez of the Hospital ClĖnic in Barcelona and colleagues compared the cognitive state of 11 depressive patients who had been treated with M-ECT treatment with 11 age- and gender-matched depressive subjects who had never received ECT.

Patients in the ECT group had received an average of 36 ECT sessions, with a mean intersession interval of 53 days.

Using a battery of neuropsychological tests, the team found that although both groups of depressed patients preserved attention function and long-term memory, the M-ECT group scored lower on the encoding of new information. In addition, frontal function test scores were significantly lower in patients treated with M-ECT.

"Compared with controls, M-ECT patients showed alterations in verbal fluency, mental flexibility, working memory and visuomotor speed," the researchers said.

However, no significant correlations were found between cognitive measures and the number of ECT sessions, total time in M-ECT or the time between treatments.

The team concludes that further longitudinal studies with larger numbers of patients are required to establish the cognitive state in patients during M-ECT. Such studies, the researchers point out, will help to determine their quality of life and everyday functioning during treatment.

Reference: Rami-Gonz·lez et al, Psychological Medicine 2003;33:345-350