Exploring the Role of Electroconvulsive Therapy in Chronic Pain Treatment

Abigail Waitz is a medical student at the Univeristy of Illinois College of Medicine in Peoria.

Introduction
Chronic pain is a complex and debilitating condition that affects millions of people worldwide, significantly decreasing their quality of life and overall well-being. Although various treatment options exist, some individuals may find limited relief from conventional therapies. In recent years, electroconvulsive therapy (ECT) has gained attention as a potential alternative for chronic pain management. This article examines the role of ECT in treating chronic pain, recent studies involving ECT for pain management, potential considerations, and future directions in research.

Electroconvulsive therapy is a medical procedure that involves the controlled induction of a brief seizure through the application of electrical currents to the brain. Historically, ECT has primarily been used to treat mental health disorders such as depression, bipolar disorder, and schizophrenia. However, recent studies have shown promise in its application for chronic pain management.¹

The exact mechanism of action by which ECT alleviates chronic pain is not yet fully understood. However, it is believed that the induced seizure activity during ECT releases neurochemicals and activates various neural pathways, leading to a modulation of pain perception. Additionally, ECT may promote neuroplasticity, which can help rewire the brain and reduce chronic pain signals. The release of endogenous opioids and the normalization of neuroendocrine functions have also been proposed as potential mechanisms of ECT's pain-relieving effects.²

Effectiveness in Chronic Pain Treatment
Several studies have reported positive outcomes in using ECT for chronic pain treatment. A 2019 review published in the Journal of ECT examined 58 cases where ECT was used specifically for chronic pain management. The review found that ECT resulted in significant pain reduction in 79% of the cases, with 52% experiencing complete remission of pain. Furthermore, ECT was found to improve overall functioning and quality of life in individuals with chronic pain. However, it is important to note that the efficacy of ECT may vary depending on the underlying cause of the chronic pain and individual patient characteristics.

A more recent systematic review and case series from 2023 had similar findings.3 In the case series, 11 patients with various chronic pain issues along with comorbid psychiatric conditions were included. Following ECT, six patients reported improvement in pain and 10 reported improvement in mood. The systematic review analyzed 109 cases. Here, 78% of cases reported improvement in pain and 96.3% reported improvement in mood. It should be noted that although there was an association between improvement in pain and mood, some patients reported improvement in pain without any improvement in mood.

To further distinguish between direct improvement in pain versus improvement in pain secondary to improved mood, a randomized controlled trial was conducted in 2022.4 This study evaluated the relationship between depression and pain during ECT treatment and throughout the follow-up period in 97 patients with treatment-resistant depression. It was found that both depression and pain subscale scores decreased significantly after ECT, although pain improved more slowly. Improvement in pain severity also was not fully explained by the improvement in depression severity, which suggests that pain can be considered a separate entity from depression.

Another major category of pain patients that may benefit from ECT is the group with somatic symptom disorder. In 2015, a retrospective chart review was performed to examine improvement in pain secondary to somatic symptom and related disorder after ECT.⁵ Twenty-eight participants were included, with 21 receiving right unilateral ECT, six receiving bifrontal ECT, and one receiving bitemporal ECT. Post-treatment, 86% of patients reported improvement in neurologic symptoms and 79% reported improvement in overall pain symptoms, suggesting that ECT could be included as part of treatment for chronic pain secondary to somatic symptom disorder, particularly in cases with comorbid mood disorders.

Many other case reports have been published, noting the improvement in various pain symptoms after administration of ECT. A case, from 2020, described a 41-year-old man with post-injury neuropathic pain comorbid with depression who experienced significant relief without relapse for 1 year after treatment.⁶ Another case, from 2022, mentioned a 68-year-old man with somatic symptom disorder who experienced significant improvement in symptoms following 6 sessions of ECT over the course of 2 weeks.⁷

Considerations and Potential Side Effects
Although ECT shows promise as an alternative treatment for chronic pain, it is important to consider certain factors. First, ECT is typically reserved for people who have not responded well to other treatment options. Additionally, ECT requires general anesthesia and can cause short-term memory loss, confusion and headache as side effects. However, these side effects are usually temporary and resolve within a few hours to days. It is crucial that patients discuss potential risks and benefits with their healthcare providers before considering ECT as a treatment option.⁸

The selection of patients for ECT should be carefully considered, taking into account their medical history, previous treatment response, and overall health. Collaborative decision making between the patient, healthcare provider, and multidisciplinary team is crucial to ensure the best possible outcome. An individualized treatment plan that incorporates ECT along with other pain management strategies may be necessary to optimize results. Factors such as pain severity, duration and impact on daily functioning should be considered when determining the appropriateness of ECT for an individual patient.

Electroconvulsive therapy has long been associated with stigma and misconceptions, mainly due to its negative historical portrayal in popular media. It is essential to address these misconceptions and provide accurate information to patients and their families. Educating patients about the potential benefits, risks, and side effects of ECT can empower them to make informed decisions about their treatment options. Open and honest communication is crucial to alleviate fears and ensure that patients are actively involved in their treatment journey.

Future Directions and Conclusion
Despite the positive findings on ECT for chronic pain, research is still in its early stages. More studies are needed to establish its long-term effectiveness, optimal treatment protocols, and potential side effects. Additionally, research should focus on identifying the most appropriate candidates for ECT because it may not be suitable for all individuals with chronic pain. Collaborative efforts between pain specialists, psychiatrists, and researchers are necessary to expand our understanding of ECT's role in chronic pain management.

Electroconvulsive therapy has shown promise as a potential alternative treatment for chronic pain. With its ability to modulate pain perception and potentially promote neuroplasticity, ECT offers a unique approach to managing chronic pain when other therapies have not been effective. However, further research is needed to establish its long-term effectiveness and safety, and to identify the most appropriate candidates for this treatment modality. In the context of multidisciplinary care and individualized treatment plans, ECT can be a valuable tool in the management of chronic pain, improving the quality of life for those who experience this debilitating condition. Continued research, collaboration, and patient education will contribute to further advancements in the field of ECT for chronic pain treatment.

References
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