NEW YORK (Reuters Health) May 16 - Patients with major depression have increased levels of brain-derived neurotrophic factor (BDNF) after a course of electroconvulsive therapy (ECT), researchers at the University of Maryland, at Baltimore report.

They believe that their findings, published in the April issue of the Journal of Clinical Psychiatry, suggest that a neurotrophic mechanism underlies the antidepressant effect of ECT.

Dr. Christopher M. Marano and colleagues conducted a prospective, self-controlled trial of 15 patients with a DSM-IV diagnosis of major depression referred to their institution for ECT.

Plasma levels of BDNF were measured before and during a course of ECT. Scores on the Hamilton Rating Scale of Depression (HAM-D) were assessed before and after therapy.

Median plasma BDNF level was 84.9 pg/mL before ECT and 141.2 pg/mL afterward. BDNF levels rose in 13 of the 15 patients with ECT.

Mean HAM-D score was 30.0 before ECT, falling to 9.0 after treatment.

D. Marano and colleagues note that "plasma BDNF holds promise as a biomarker of the neurotrophic and antidepressant effects of ECT and merits further study to assess its clinical utility in determining the number and frequency of treatments required for therapeutic response."

J Clin Psychiatry 2007;68:512-517.