Effect of deep brain stimulation in patients with severe and treatment-resistant obsessive-compulsive disorder

ObjectiveTo provide a timely, rigorous and continuously updated summary of the available evidence on the effectiveness of deep brain stimulation (DBS) in people with severe and refractory obsessive-compulsive disorder (OCD). MethodsWe conducted a systematic literature review of intervention, as the baseline synthesis report of a living evidence approach. We followed the methodological framework by Elliot et al. 2014. The L.OVE platform from Epistemonikos was used for identification, screening and pre-selection of studies. Systematic reviews (SR) and randomized clinical trials (RCT) evaluating the use of DBS in patients with severe and refractory OCD were included. Data extraction and risk of bias assessment were performed in duplicate using appropriate instruments. Primary outcomes were symptom severity (efficacy) and adverse events (safety), secondary outcomes were quality of life, functionality, effect on cognitive function, patient perception and values. Evidence certainty was assessed with the GRADE approach. ResultsThe searches identified 45 references for full text review, finally, 16 SRs and 12 crossover RCT (112 patients) were included. The pooled estimates suggested a favorable effect of DBS on reducing symptoms measured by Y-BOCS score in the short term (MD=7.3 points, 95%CI: 3.9-10.6, p <0.0001) and the long term (MD=14.8 (95% CI: 12.1 - 17.5) (p <0 . 0001), with high and moderate certainty evidence, respectively. The estimated pooled incidence of permanent serious adverse events (SAE) was 6% (95% CI: 0%-19%), and surgical SAE was 9% (95% CI: 2%-18%); both with very low certainty due to serious imprecision. Non-pooled results from individual studies also suggested benefits of the interventions on quality of life and cognitive function. ConclusionsDeep brain stimulation of proposed targets for refractory obsessive-compulsive disorder has a large beneficial effect on reducing symptoms severity in the short and long term. Implantation has a low incidence of adverse events, and a high incidence of non-serious adverse events during the stimulation calibration period. Benefit to harm balance should consider uncertainty on the risk of adverse events related to the surgical procedure and to the device, and appears favorable given its large effects on symptom reduction.