IntroductionThe potential benefits of electroconvulsive therapy (ECT) in chronic pain and several theories for its mechanism have been reported in the past, but mixed findings have also been reported. In the current systematic review and case series, our primary aim was to assess whether pain and functional outcomes are improved after ECT in patients with chronic pain. Secondary objectives included examining whether psychiatric improvement, specific pain diagnoses, and demographic or medical characteristics were associated with differences in pain treatment response. MethodsWe performed a retrospective chart review to identify patients with chronic pain diagnoses for more than 3 months prior to the initiation of ECT and a systematic literature search on electronic databases for studies on chronic pain outcomes after ECT. ResultsEleven patients with various chronic pain diagnoses and comorbid psychiatric conditions were identified in the case series. Six patients reported improvement in pain while 10 patients reported improvement in mood following ECT. Systematic review identified 22 articles reporting a total of 109 cases. Eighty-five (78%) of cases reported reduction in pain while 96.3% of the patients with a comorbid psychiatric diagnosis reported improvement in mood symptoms post-ECT. While there was an association between improvement in mood and pain in studies with numeric ratings in both outcomes (r = 0.61; p < 0.001), some patients reported pain improvement without improvement in mood in both the case series and the pooled analysis of cases in the review. Certain pain diagnoses such as CRPS, phantom limb pain, neuropathic pain, and low back pain have consistently reported benefits and should be further studied in future studies with matched case controls. ConclusionECT may be offered to patients with certain pain conditions who have not responded sufficiently to conventional therapies, particularly when comorbid mood symptoms are present. Improved documentation practices on the outcomes in chronic pain patients receiving ECT will help generate more studies that are needed on this topic.
