This cohort study included ten SCC DBS participants with treatment-resistant depression. The setting was at home, and the intervention or exposure was SCC DBS with at-home LFP data collection. No comparator was reported. The primary outcome was a biomarker of stable recovery. Secondary outcomes included generalizability across subject cohorts and devices, robustness to time of day and stimulation status, symptom specificity, sensitivity, stability, relationship to pre-DBS white matter structure, and relationship to network function. The follow-up was longitudinal.
Main results indicated that the biomarker of stable recovery generalizes across subject cohorts and devices, is robust to common potential confounds (including time of day and stimulation status), and shows symptom specificity, sensitivity, and stability. Absolute numbers, p-values, or confidence intervals were not reported for these outcomes. The direction of effect was not reported.
Safety and tolerability data were not reported; adverse events, serious adverse events, discontinuations, and overall tolerability were not reported. Funding or conflicts were not reported. Limitations included the small sample size of ten participants and the absence of a control group. The study design was a cohort study, not an RCT.
Practice relevance suggests support for clinical decision making. However, because the evidence is observational and key details like adverse events are missing, clinicians should interpret these results with caution before altering management strategies for treatment-resistant depression.
View Original Abstract ↓
Subcallosal cingulate cortex (SCC) deep brain stimulation (DBS) can provide relief for individuals with Treatment Resistant Depression (TRD), but ongoing clinical management remains challenging due to nonspecific symptom fluctuations that can obscure core depression recovery on standard rating scales. Objective, stable biomarkers that selectively track the therapeutic effects of SCC DBS are therefore essential for developing principled decision support systems to guide stimulation adjustments. Recent bidirectional DBS systems enable chronic recording of local field potentials (LFPs) and prior work using the Activa PC+S device identified an electrophysiological signature of stable clinical recovery. However, translation to practical clinical deployment requires demonstrating that this biomarker is robustly generalizable, specific to the impact of the DBS therapy, and deployable in real-world recording contexts. To address this need, we developed an at-home SCC LFP data collection platform (built on the Medtronic Summit RC+S system) enabling at home data collection for a new cohort of ten SCC DBS participants with TRD (ClinicalTrials.gov identifier NCT04106466). Using longitudinal LFP recordings collected from this system, we report findings demonstrating that the previously reported biomarker of stable recovery generalizes across subject cohorts and devices, is robust to common potential confounds (including time of day and stimulation status), and shows symptom specificity, sensitivity and stability necessary to support clinical decision making. Across both cohorts, biomarker changes show relationships to pre-DBS white matter structure and network function measured using diffusion MRI and resting-state functional MRI (rsFMRI). These findings replicating and extending previous findings support the biomarker's utility as a foundation for scalable, electrophysiology-informed decision support in SCC DBS.