AT THE ECNP CONGRESS
VIENNA (FRONTLINE MEDICAL NEWS) – Low-dose ketamine provided no benefit as adjunctive anesthesia for severely depressed patients undergoing electroconvulsive therapy in the randomized, multicenter U.K. Ketamine-ECT Study, Ian Anderson, MD, reported at the annual congress of the European College of Neuropsychopharmacology.
The hope was that ketamine would lessen the cognitive impairment that is a prominent side effect of ECT. It’s thought that this cognitive impairment results from treatment-induced excessive stimulation of glutamate receptors, and ketamine is a glutamate antagonist, explained Dr. Anderson of the University of Manchester (England).
He and his coinvestigators had also hypothesized that ketamine might result in more rapid improvement in depression in patients undergoing ECT, since a single intravenous infusion of the drug has been shown to produce an extremely rapid, albeit temporary, antidepressant effect. But this was not borne out in the Ketamine-ECT Study .
Dr. Anderson reported on 70 severely depressed patients who were randomized to ketamine at 0.5 mg/kg or saline as an adjunct to standard propofol anesthesia for their course of weekly ECT sessions at seven U.K. mental health centers.
The primary study endpoint was the delayed verbal recall score on the Hopkins Verbal Learning Test–Revised after four ECT sessions, which was midway through the full course of treatment. Blinded assessors found no significant difference between the ketamine and placebo groups then. Nor were significant differences evident at prespecified further assessments 1 and 4 months after conclusion of the treatment program.
Secondary outcomes comprised of cognitive measures of verbal fluency, and autobiographical, working, and visual memory also proved similar in the two study arms, as did assessments of quality of life, safety, and tolerability.
At the end of the full course of ECT, 39% of the ketamine group were categorized as being in remission based upon at least a 50% drop from their baseline score on the Montgomery-Åsberg Depression Rating Scale ( MADRS ) with a final score of 10 or less, as were 35% of controls. Forty-nine percent of the ketamine group and 60% of controls were categorized as treatment responders, meaning their MADRS score dropped by at least 50% but their final score was greater than 10.
No serious adverse reactions to ketamine occurred.
The study was funded by the U.K’s National Institute for Health Research and the Medical Research Council. Dr. Anderson reported having no relevant financial conflicts.
