Maintenance transcranial magnetic stimulation reduces depression relapse: a propensity-adjusted analysis

Background: The effectiveness of repetitive transcranial magnetic stimulation (TMS) is well established while studies of maintenance TMS are lacking. We aim here to determine whether maintenance is associated to a decrease in the relapse rate of depression, following successful acute treatment.

Methods: We enrolled 59 consecutive patients with pharmacoresistant depression who have responded (>50% decrease in symptom severity) up to 6 weeks of acute TMS treatment. These patients received either 20 weeks of maintenance TMS (n=37) or no additional TMS treatment (n=22). We performed propensity adjusted-analysis to examine the association between the relapse rate over this 20-week period and maintenance TMS. Propensity analysis eliminated differences in baseline characteristics between patient with and without maintenance TMS and approximated the conditions of random site-of-treatment assignment.

Results: At 20 weeks, relapse rate was significantly different between the two groups (p=0.004, propensity analysis): 14 patients in the maintenance TMS group (37.8%) vs. 18 in the non-maintenance TMS group (81.8%), with an adjusted Hazard Ratio (HR)=0.288 (0.124-0.669).

Conclusions: Maintenance TMS was associated with a significantly lower relapse rate in patients with pharmacoresistant depression in routine practice among responders.