This trial used the most aggressive treatment parameters to date: 75 10-Hz, 4-second trains at 120% MT with a 26-second ITI, delivering 3,000 pulses per treatment over an average of 26 sessions. To maintain an adequate blind, the study utilized sham and active coils with similar appearances, placement, and acoustic properties. The sham coil had an embedded aluminum shield, which limited the magnetic energy reaching the cortex to ≤10% of the active coil. Although there was no assessment of the adequacy of the blind in this trial:
- subjects were naive to TMS in the sham-controlled phase
- TMS operators did not assess efficacy
- TMS operators and subjects did not discuss the treatment experience with the efficacy raters.
Compared with those who received the sham procedure, subjects who received active TMS showed significantly better response rates on the Montgomery-Åsberg Depression Rating Scale (MADRS) at weeks 4 and 6. Similar results were found for the 17- and 24-item HDRS. At 6 weeks, the remission rate (defined as a MADRS score
A post-hoc analysis found that the greatest benefit occurred in patients who had only 1 failed adequate antidepressant trial (effect size=0.83).5
TMS vs ECT. Dowd et al6 summarized 8 published trials that compared TMS with electroconvulsive therapy (ECT) for severe depression:
- 5 reported equivalent efficacy
- 1 found unilateral ECT (UL-ECT) and bilateral ECT (BL-ECT) superior to TMS
- 1 reported UL-ECT superior to TMS
- 1 found UL-ECT plus medication superior to TMS monotherapy in patients with psychosis but comparable in efficacy to TMS in the absence of psychosis.
These results need to be interpreted with caution because of the studies’ diverse designs, nonblinded assessments, and small sample sizes.
Tolerability and safety
The most frequently reported adverse effects of TMS are headache and pain at the site of stimulation. Seizures had been reported in early trials, but the extremely low occurrence has been much lower since Wasserman7 published consensus guidelines on the safe use of TMS in 1996.
Janicak et al8 examined safety data from the 3-phase trial mentioned above, which included >10,000 cumulative treatment sessions. TMS was well-tolerated, with a low discontinuation rate associated with adverse effects: 4.5% in the active treatment group versus 3.4% in the sham TMS procedure group. No deaths, seizures, or cases of treatment-emergent mania occurred. The most commonly reported adverse effects were transient headache and discomfort at the stimulation site. Most patients acclimated to these effects in the first week. No changes were seen in cognitive functioning or auditory thresholds.
As in previous studies, TMS was safely combined with antidepressants in the third phase of this trial; however, patients at risk for seizure or on medications that could lower the seizure threshold were excluded. Thus, risk of seizure may be increased under these conditions. TMS is contraindicated for patients with implanted metallic devices or nonremovable objects in or around the head, except for dental hardware or braces.
- For availability information, contact the manufacturer, Neuronetics, at (877) 6000-7555 or www.NeuroStarTMS.com.
Disclosures
Drs. Dowd, Rado, and Janicak receive research support from and are consultants to Neuronetics, Inc.
Dr. Welch receives research support from Neuronetics, Inc.