Researchers Evaluate Pain Management Therapy Intervention to Treat Chronic Postherpetic Neuralgia

With findings published in the European Journal of Medical Research, researchers assessed the efficacy and safety of short-term spinal cord stimulation (tSCS) in treating herpes zoster-associated pain (HZAP). According to the study authors, tSCS is a therapy intervention used in pain management. The researchers conducted a clinical study among individuals with subacute and chronic postherpetic neuralgia (PHN).¹

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Advanced herpes zoster is considered PHN, which is the most common complication of shingles. PHN causes a burning pain in the nerves and skin, lasting long after the initial rash and blisters of shingles clears. Symptoms of PHN are often limited to the area of skin where the shingles outbreak occurred, including pain that lasts 3 months or longer, not being able to stand light touch, and itching or loss of feeling.²

Zoster-associated neuralgia, a neuropathic pain arising from shingles, can evolve into PHN, emphasizing the critical need for effective interventions to prevent this debilitating condition, although optimal treatment strategies remain elusive.¹

However, despite ongoing debate regarding herpes zoster staging, with varying definitions of PHN, current research acknowledges its significant impact on quality of life and the limitations of existing treatments, including nerve blocks and epidural injections. This study hypothesizes that short-term spinal cord stimulation (SCS) is a safe and effective treatment for both subacute and chronic PHN, aiming to assess its efficacy in pain relief and its potential to prevent the transition from subacute to chronic PHN.¹

The study included a total of 135 individuals with HZAP who were divided into 2 groups. The experimental group received short-term spinal cord stimulation treatment and pharmacologic treatment, and the control group received conventional medical treatment and epidural nerve block therapy.¹

The Numerical Rating Scale (NRS) was used to evaluate treatment efficacy based on the reduction in pain intensity among the patients. The NRS reduction scores were defined as greater than 75% is a significant effect; reduction between 50% and 75% is a good effect; reduction between 25% and 50% is a moderate effect; and reduction of less than 25% is no effect.¹

The results demonstrated that at 1 month, the SCS group had significantly greater pain reduction (P < 0.01) compared with the nerve block group. Specifically, 75.7% of SCS patients experienced significant pain relief compared with 24.3% in the nerve block group (P < 0.001). Additionally, SCS significantly improved sleep quality within 1 month, with significantly lower Pittsburgh Sleep Quality Index (PSQI) scores in the SCS group compared to the nerve block group. This effect was maintained at 3 months.¹

At 3 months, the SCS group showed better improvement in depression scores (PHQ-9) compared with the nerve block group, suggesting a more significant regulatory effect of SCS on the central nervous system. The long-term efficacy of SCS gradually diminished, with the difference in pain relief between the 2 groups narrowing at 6 months and becoming insignificant at 12 months, according to study authors.¹

Further results displayed that SCS treatment, along with pre-treatment PSQI and PHQ-9 scores, were strongly correlated with better overall efficacy (β = 0.914, P < 0.001). However, the study authors noted that SCS faced challenges maintaining long-term efficacy in pain relief, suggesting the need for further investigation into strategies to prolong its effects, such as combination therapies or longer-term stimulation.¹

The findings suggest that tSCS could provide long-term pain relief and improve the overall quality of life for individuals with HZAP and PHN. The results demonstrated that tSCS is safe and effective, but further trials need to be conducted to determine the long-term efficacy maintencance.¹

REFERENCES

1. Clinical study of short-term spinal cord stimulation for herpes zoster-associated pain. European Journal of Medical Research. News release. December 19, 2024. Accessed December 23, 2024. https://pmc.ncbi.nlm.nih.gov/articles/PMC11657820/.

2. Postherpetic neuralgia. Mayo Clinic. News release. February 10, 2023. Accessed December 23, 2024. https://www.mayoclinic.org/diseases-conditions/postherpetic-neuralgia/symptoms-causes/syc-20376588.