Obsesif kompulsif bozuklukta noninvaziv derin beyin stimülasyonuna yanıtı öngörmede elektroensefalografi bulgularının kullanımı

The aim of this study was to investigate the quantitative electroencephalography (QEEG) findings that affect the response to deep transcranial magnetic stimulation (dTMS) by examining the relationship between the pre-treatment resting-state QEEG data of obsessive compulsive disorder (OCD) patients and their response to dTMS. To this end, the data of 52 OCD patients (mean age: 31.88±11.51 years, M/F: 23/29) aged between 18-65 years who applied to the Private Psychiatry Clinic of Prof. Dr. Kemal Arıkan (İstanbul, Turkey) between Jan 2018 and May 2019 and to whom dTMS was applied were retrospectively examined. The data were collected through sociodemographic and clinical data form, Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Beck Depression Inventory (BDI), and resting-state EEG recording. Fourier analysis was performed by averaging across eyes-closed 2-second EEG epochs without artifacts, and for each of the 19 monopolar derivations, absolute power (μV2) was calculated for the delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), beta (13-30 Hz), and gamma (30-70 Hz) frequency bands. By evaluating the pre-treatment and post-treatment Y-BOCS scores of the participants, patients with a decrease in the scores of 30% and above were named "responsive group" (n=42), and those without it were named "non-responsive group" (n=10), and the pre-treatment QEEG data of both groups were statistically compared. All statistical analyses were performed using IBM SPSS Statistics 25.0. P<0.05 was accepted to be statistically significant. The alpha and theta absolute power in all electrodes was found to be higher in the responsive group compared to the non-responsive group. No significant difference was observed between the two groups in terms of sociodemographic data and pre-treatment Y-BOCS_total, Y-BOCS_obsession, Y-BOCS_compulsion, and BDI scores. However, the time occupied by obsessions was found to be higher in the responsive group. In conclusion, it was revealed that the increase in the pre-treatment alpha and theta absolute power might be beneficial in predicting OCD patients who would respond well to dTMS. We suggest that use of such biomarkers can assist clinicians in individualizing OCD treatment and thus achieving optimal treatment outcomes. Key words: Obsessive Compulsive Disorder; Deep Transcranial Magnetic Stimulation; Electroencephalography