The Impact of Ventral Capsule Deep Brain Stimulation Acute Behavioral Effects on Psychotherapy

Introduction: Positive acute behavioral effects (PABEs; e.g. smiling, laughing, mood improvements, energy, and decreased anxiety) are commonly observed during programming of deep brain stimulation (DBS) for obsessive compulsive disorder (OCD); however, the clinical significance of PABEs is not yet understood. Here we analyze associations between PABEs, and OCD symptom severity following exposure and response prevention (ERP), the gold-standard psychotherapeutic for OCD.

Methods: Data from 21 DBS-OCD patients were analyzed; ten completed 15 postoperative ERP sessions. Total unique PABEs observed during monopolar survey programming of each lead were compared to outcomes for both groups. OCD symptoms were measured using either the Yale Brown Obsessive Compulsive Scale (YBOCS), or YBOCS-II. Changes in YBOCS scores (pre-to-post treatment difference scores) were calculated and correlated with PABEs. Finally, we compared PABEs to the lowest level of reported stress after being subjected to an exposure during ERP using 32 ERP sessions across 8 patients.

Results: Spearman correlation between PABEs and pre-post YBOCS-II difference scores for patients undergoing ERP was rs=-0.64 (p=0.046), and for those not getting ERP, rs=0.204 (p=0.54). Fisher exact test comparing the correlations yielded p=0.03 (relationship was stronger in those undergoing ERP). Spearman analysis between YBOCS decrease during ERP and PABEs also showed a strong correlation (rs=-0.857, p= < 0.01). Using a mixed effects model the lowest reported stress level after exposure during ERP was found to be strongly negatively correlated with behavioral effects (p = < 0.01).

Conclusion : Data suggest total unique PABEs during initial programming correlates with DBS for OCD outcomes only in patients receiving intensive ERP. Additionally, both the change in symptomatic burden during ERP, and the tolerability of ERP, strongly correlate with the number of unique acute behavioral effects. This suggests that when DBS elicits these effects, patients previously not responsive to ERP may newly be able to benefit from psychotherapy.