Dissecting Treatment Response in Depression: A Symptom Network Analysis of rTMS Effects

Increasing evidence suggests that personalizing treatment for depression requires a refined understanding of how interventions affect distinct symptom domains, rather than focusing on total symptom scores. Different treatments may influence specific symptoms in unique ways, and these symptoms can interact dynamically - a relationship that can be explored using network modeling. In this observational, naturalistic study, we applied single-symptom and network analyses to examine symptom changes in depressed inpatients (total n=108) receiving either treatment as usual (TAU; psychotherapy and pharmacotherapy) (n=62) or adjunctive repetitive transcranial magnetic stimulation (rTMS) (n=46). While overall symptom reduction and changes within individual symptom domains did not differ significantly between groups, network analyses revealed marked differences in symptom interrelations: In the TAU group, loss of energy and depressed mood emerged as the most central symptoms within the course of symptom change, whereas in the rTMS group, loss of interest and decreased concentration were most central and influential. These findings highlight the importance of examining treatment effects at the single-symptom level and considering the complex interconnections among symptoms when evaluating and personalizing interventions for depression.