Predictors of deep brain stimulation response in patients with obsessive compulsive disorder: a systematic review and meta-analysis.

Obsessive-compulsive disorder (OCD) is a chronic and debilitating condition, often resistant to conventional treatments. Deep brain stimulation (DBS) emerges as a promising intervention, but its efficacy varies among patients, underscoring the need to understand the predictive factors influencing its outcomes. To evaluate and compare disease and patient characteristics in their ability to predict response to DBS in OCD patients. All major databases were searched for original studies. This study differentiated responders, partial responders, and non-responders based on relative post-treatment Y-BOCS score changes and pre-defined Y-BOCS cut-off scores. Clinical predictors were assessed using qualitative synthesis, univariate analysis, stepwise and regularisation-tuned multivariate linear and logistic regression analyses. The meta-analysis, comprising 28 studies with a pooled sample of 296 patients, found that higher baseline Y-BOCS scores significantly predicted favourable long-term DBS response in the multivariate regression analysis (p = 0.0075), whereas antipsychotic use was identified as a significant predictor of non-response (p = 0.0138). In the univariate analysis, antidepressant use was negatively associated with DBS response (p = 0.027), while anxiolytic use was positively associated with short-term improvement (p = 0.025). Symmetry, hoarding, and perfectionism symptomology at baseline predicted reduced short-term improvement (p = 0.027). Adjusting for stimulation target, aggression, and intrusive thoughts, baseline symptomology emerged as a positive predictor of DBS response in the multivariate model (p = 0.0475). In the multivariate analysis, excluding studies with high risk of bias, the symptom combination anxiety, avoidance, and fear was associated with DBS response (p = 0.024). Disease duration, gender, anatomical target location, and age did not predict DBS response (p > 0.05). This study found that a higher baseline severity of OCD symptoms significantly predicted a greater likelihood of long-term response to DBS. In contrast, the use of antipsychotics and antidepressants was associated with poorer outcomes, while anxiolytic use appeared to support short-term improvement. Compulsive symptom profiles characterised by symmetry, hoarding, and perfectionism were associated with non-response, whereas the presence of aggression and intrusive thoughts, as well as anxiety, fear and avoidance symptomology, was linked to a positive response. Further research with homogenous methodology and outcome reporting, as well as randomised control trials, are required to further elucidate these phenotypes and allow for more personalised and, thus, likely more effective DBS treatment strategies for all OCD patients.