Journal: Brain Stimulation 13:1000-1001 (2020)
Authors: Harmelech T, Tendler A, Roth Y, Zangen A
Background:
MDD is the most common comorbidity with OCD; more than 50% of OCD patients meet lifetime criteria for MDD or dysthymia. Depression can significantly worsen OCD treatment outcomes and elevate the risk for suicide. While the multi-center-tested and FDA indicated Deep TMS treatment for OCD uses the H7 Coil to target dorsomedial prefrontal cortex (dmPFC) and anterior cingulate cortex (ACC), the treatment for MDD uses the H1 Coil to target the dorsolateral prefrontal cortex (dlPFC) bilaterally with preference to the left. However, a recent case series (N=9) indicated the potential of effectiveness of H7 Coil treatment in MDD as well.
Objective:
Examine whether OCD patients with MDD comorbidity will benefit sufficiently from stimulation to the dmPFC and ACC for both their OCD symptoms and their MDD symptoms, negating the need for the standard stimulation of the left dlPFC.
Methods:
A post hoc analysis of the OCD pivotal trial data was performed to compare the Yale-Brown Obsessive–Compulsive Scale (YBOCS) and Hamilton Depression Rating Scale (HDRS) data of a subset of OCD patients with MDD comorbidity (YBOCS>20; HDRS21>16) between the active Deep TMS (N=9) and sham (N=10) groups.
Results:
In the subset of patients included in this analysis, the decrease in YBOCS scores from baseline was significantly larger for the active Deep TMS group compared to sham starting at week 2 (p=0.02) and sustained until the end of the trial. Notably, this effect was sustained and even enhanced at the 1-month follow-up assessment (p=0.002). This significant difference at all time points is remarkable in light of the very small sample size. A statistically significant decrease in HDRS scores was observed from baseline at all time points (p<0.05 for weeks2–4, p<0.01 for week 6, p<0.005 for 1-month follow-up) in the active Deep TMS group. Conversely, no significant decrease in HDRS scores was observed for the sham group at any timepoint (p>0.05). Although this decrease in HDRS from baseline was larger for the active Deep TMS group compared to the sham group, this difference wasn’t statistically significant (p>0.1).
Conclusion:
While the decrease in HDRS scores wasn’t statistically significantly larger in the active Deep TMS group compared to the sham group, it is reasonable to assume that this could be due to the small sample size. The significant effect within the active Deep TMS (but not sham) group deserves attention and follow-up corroboration.
