Cortical Thickness in the Right Anterior Cingulate Cortex Relates to Clinical Response to Left Prefrontal Accelerated Intermittent Theta Burst Stimulation: An Exploratory Study

Abstract

Objectives: Accelerated intermittent theta burst stimulation (aiTBS) is a promising treatment option for depressed patients. However, there is a large interindividual variability in clinical effectiveness and individual biomarkers to guide treatment outcome are needed.Materials and Methods: Here, the relation between cortical thickness and clinical response (17-item Hamilton Depression Rating Scale) was studied using anatomical MRI data of 50 depressed patients who were included in a randomized, sham-controlled, double-blinded, cross-over aiTBS design (NCT01832805).Results: Baseline cortical thickness in the right caudal part of the anterior cingulate cortex (cACC) was significantly correlated with direct clinical responses in the subgroup who received active aiTBS during the first stimulation week. No correlations were found between baseline cortical thickness and delayed clinical effectiveness. In this particular region, longitudinal changes in cortical thickness were significantly correlated with clinical effectiveness. Furthermore, direct changes in cortical thickness in the right cACC showed predictive potential of delayed clinical responses. Conclusion:Cortical thickness within the right cACC might be an important biomarker to predict clinical responses to aiTBS. Additional studies are warranted to substantiate the specific biomarker potential of these parts of the ACC.

Baseline Clinical and Neuroimaging Biomarkers of Treatment Response to High-Frequency rTMS Over the Left DLPFC for Resistant Depression

“…We did not find a statistically significant link between cortical thickness and treatment response. The link between cortical thickness and the responses to ECT ( 62 ), tDCS ( 63 ), and rTMS ( 17 , 18 ) has been reported before. Boes et al ( 18 ) describe that cortical thickness in the left rostral anterior cingulate cortex region correlates with rTMS treatment response in 48 TRD patients treated with HF (10 Hz) rTMS over the left DLPFC baseline.…”

“…In fact, patients with thinner cortex before treatment tended to have the most clinical improvement. Baeken et al ( 17 ) recently suggested that baseline cortical thickness in the right caudal part of the anterior cingulate cortex was significantly correlated with direct clinical responses in the subgroup that received active aiTBS (21 patients) over the left DLPFC during the first stimulation week, but no correlation was found with delayed response. In this study, we did not confirm the results of these two preceding studies.…”

“…Results that did not pass corrections were not considered. Following the literature, the analysis was carried out for the measures of thicknesses and volumes on the left and right hemispheres with a smoothing kernel of 15 mm ( 17 , 18 ). We added the clinical variables as nuisance factors if their p -value in the univariate tests was inferior to 0.2.…”

“…These imaging methods are rarely available in clinical settings, need specialized data processing, and are costly. Therefore, as suggested by Baeken et al, ( 17 ), simpler biomarkers like cortical thickness measures, as derived from anatomical MRI data, could be more feasible in current clinical practice. Indeed, to date, two studies have explored cortical thickness before stimulation as a predictor of rTMS response in patients with MDD ( 17 , 18 ).…”

The effects of noninvasive brain stimulation on heart rate and heart rate variability: A systematic review and meta‐analysis

“…Furthermore, recent studies have shown that not only the depth of a particular cortical region but also its thickness may influence the outcome of NIBS interventions. As such, the cortical thickness of regions such as the prefrontal (Bulubas et al, 2019; Filmer et al, 2019), cingulate (Baeken et al, 2021; Boes et al, 2018), and motor cortex (Conde et al, 2012) was found to predict the efficacy of NIBS targeting these areas. In addition, it has been reported that cortical thickness of prefrontal and insular regions positively correlates with the measures of resting HRV (Koenig et al, 2021).…”