ECT, rTMS, and deepTMS in pharmacoresistant drug-free patients with unipolar depression: a comparative review

Background: Biological treatments are considered as additional options for the treatment of resistant unipolar depression. Controversial data exist about the efficacy and tolerability of three of the most used somatic treatments: electroconvulsive therapy (ECT), transcranial magnetic stimulation (rTMS), and deep transcranial magnetic stimulation (deepTMS). The aim of this review is to investigate and compare the efficacy and tolerability of these three techniques in drug-free patients with pharmacoresistant unipolar depression. Methods: Three independent reviewers extracted data and assessed the quality of methodological reporting of selected studies. The first outcome was the clinical response to the three different techniques defined as a percentage improvement of Hamilton Depression Rating Scale (HDRS). The second outcome was the evaluation of their neuropsychological effects. The third outcome was the evaluation of the number of remitted patients; remission was defined as an absolute HDRS-24 score of <= 11 or as an absolute HDRS-17 score of <= 8. Tolerability was the fourth outcome; it was evaluated by examining the number of dropped-out patients. Results: The comparative evaluation of HDRS percentage variations shows ECT as the most effective method after 4 weeks of therapy; on the other hand, a better efficacy is obtainable by deepTMS after 2 weeks of therapy. DeepTMS is the technique that gives the best improvement of cognitive performances. The percentage of remitted patients obtained with ECT treatment is the same obtained in the deepTMS group. Both techniques have a remitted patients percentage two times larger than the rTMS. DeepTMS shows a tolerability, measured by the number of dropped-out patients, worse than ECT. Conclusion: Our investigation confirms the great therapeutic power of ECT. DeepTMS seems to be the only therapy that provides a substantial improvement of both depressive symptoms and cognitive performances; nevertheless it is characterized by a poor tolerability. rTMS seems to provide a better tolerability for patients, but its therapeutic efficacy is lower. Considering the small therapeutic efficacy of deepTMS in the last 2 weeks of treatment, it could be reasonable to shorten the standard period of deepTMS treatment from 4 to 2 weeks, expecting a reduction of dropped-out patients and thus optimizing the treatment outcome.