Effectiveness of Deep Repetitive TMS with the H7 Coil in the Treatment of Comorbid MDD and OCD

Obsessive Compulsive Disorder (OCD) is a neuropsychiatric disorder that affects 2-3% of the population in the United States of America. OCD patients frequently have comorbid psychiatric disorders. The most common comorbid diagnosis is major depressive disorder (MDD).

In 2018, the U.S. Food and Drug Administration (FDA) approved the effectiveness of the high-frequency deep repetitive transcranial magnetic stimulation (dTMS) administered with the H7 coil (on the dorsomedial prefrontal and anterior cingulate cortices (DMPFC-ACC) regions) in the treatment of resistant OCD.

It was a mystery whether patients with comorbid MDD would require two different dTMS treatments consisting of H1 (the H1 coil used for the treatment of depression) and H7 respectively, or whether it was possible to treat the MDDs of patients with ODD only by using the H7.

In the current study, the patients diagnosed with OCD and at least mild MDD were subjected to the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) in order to measure the severity of OCD before and after the treatment, along with the Hamilton Depression Rating Scale (HDRS) to measure the severity of depression, and the treatment was administered through the FDA-approved dTMS protocol.

At the beginning, a total of 59 OCD patients with at least mild MDD were treated with the H7 dTMS. After 5 sessions of dTMS, and in the subsequent measurements carried out at random times, a significant decline was observed both in the YBOCS and MDD scores. After 30 sessions, the YBOCS score reduced by 30% and MDD scores by 38% on average, and it was seen that the treatment was beneficial in both disorders.

A constant state of improvement was observed in more dTMS sessions that went up to 40 sessions. The change between the YBOCS and MDD scores was found to be quite significantly correlated.

It further explains the underlying mechanism of the improvement observed in MDD after the OCD – dTMS treatment administered with the H7 coil. Although it is debatable that the improvement in MDD is an indirect result of the alleviation in the OCD symptoms, another convincing hypothesis states that the stimulation on the DMPFC-ACC directly heals the MDD symptoms irrespective of OCD. In recent years, there has been an accumulation of evidences which show that the stimulation of the DMPFC and ACC at higher frequencies with deeper helices is adequate for the MDD treatment.

REFERENCES:
Tendler, A., Roth, Y., & Harmelech, T. (2021). Deep repetitive TMS with the H7 coil is sufficient to treat comorbid MDD and OCD. Brain Stimulation: Basic, Translational, and Clinical Research in Neuromodulation, 14(3), 658-661.