BACKGROUND

Four ablative neurosurgical procedures are used in the treatment of refractory psychiatric illness. The long-term effects of these procedures on psychiatric symptoms across disorders has never been synthesised and meta-analysed.

METHODS

A preregistered systematic review was performed on studies reporting clinical results following ablative psychiatric neurosurgery. Four possible outcome measures were extracted for each study: depression, obsessive-compulsive symptoms, anxiety and clinical global impression. Effect sizes were calculated using Hedge's g. Equipercentile linking was used to convert symptom scores to a common metric. The main outcome measures were the magnitude of improvement in depression, obsessive compulsive symptoms, anxiety and clinical global impression. The secondary outcome was a subgroup analysis comparing the magnitude of symptom changes between the four procedures.

RESULTS

Of 943 articles, 43 studies reporting data from 1414 unique patients, were included for pooled effects estimates with a random-effects meta-analysis. Results showed that there was a large effect size for improvements in depression (g=1.27; p<0.0001), obsessive-compulsive symptoms (g=2.25; p<0.0001) and anxiety (g=1.76; p<0.0001). The pooled clinical global impression improvement score was 2.36 (p<0.0001). On subgroup analysis, there was only a significant degree of heterogeneity in effect sizes between procedure types for anxiety symptoms, with capsulotomy resulting in a greater reduction in anxiety than cingulotomy.

CONCLUSIONS

Contemporary ablative neurosurgical procedures were significantly associated with improvements in depression, obsessive-compulsive symptoms, anxiety and clinical global impression.

PROSPERO REGISTRATION NUMBER

CRD42020164784.