[Efficacy and safety of high-voltage pulsed radiofrequency combined with pregabalin on severe thoracic postherpetic neuralgia]

Objective: To investigate the efficacy and safety of high-voltage pulse radiofrequency combined with pregabalin on severe thoracic postherpetic neuralgia (PHN). Methods: A total of 103 patients with PHN who were admitted to the Department of Pain Medicine of Henan Provincial People's Hospital from May 2020 to May 2022 were retrospectively selected, including 50 males and 53 females, and aged 40 to 79 (65.4±9.2) years. The patients were divided into two groups according to the treatment methods they received: the control group (n=51) and the study group (n=52). The patients in the control group were treated with oral pregabalin, and the patients in the study group received pregabalin plus high-voltage pulse radiofrequency therapy. The pain intensity and efficacy of the two groups were evaluated before treatment and 4 weeks after treatment. The pain intensity, the sleep quality and the efficacy of treatment was evaluated by visual analogue scale (VAS) score, Pittsburgh Sleep Quality Index (PSQI) score and nimodipine method, respectively. The levels of pain factors including serum neuropeptide Y (NPY), prostaglandin E2 (PGE2), substance P (SP) and β-Endorphin were measured. The differences of the above indicators and the incidence of adverse reactions were compared between the two groups. Results: The VAS scores and PSQI scores of the study group and the control group before treatment were (7.94±0.76), (8.20±0.81), (16.84±3.90) and (16.29±3.84), respectively, with no statistically significant difference (both P>0.05). After 4 weeks of treatment, the VAS scores and PSQI scores of the two groups were (2.84±0.80), (3.35±0.87), (6.78±1.90) and (7.98±2.40), respectively, and the VAS score and PSQI score in the study group were lower than those in the control group (both P<0.05). Serum levels of NPY, PGE2, SP and β-Endorphin were (298.5±31.0) ng/L, (92.3±11.0) μg/L, (156.8±21.4) ng/L, and (8.6±1.6) ng/L in the study group and (304.2±28.6) ng/L, (94.4±12.9) μg/L, (152.7±23.8) ng/L and (8.2±1.8) ng/L in the control group, with no significant differences (all P>0.05). After 4 weeks of treatment, levels of NPY, PGE2, SP and β-Endorphin were (240.7±26.8) ng/L, (74.4±8.6) μg/L, (108.9±15.7) ng/L and (4.4±0.9) ng/L, which were lower than those in the control group [(268.1±29.4) ng/L, (79.7±8.3) μg/L, (115.2±16.2) ng/L, (5.2±1.3) ng/L, respectively], with statistically significant differences (all P<0.05). After treatment, 29 cases were cured, 16 cases were markedly effective and 6 cases were effective in the study group, while 16 cases, 24 cases and 8 cases were cured, markedly effective and effective in the control group. The overall efficacy of patients in the study group was better than that in the control group (Z=-2.32, P=0.018). The incidence of adverse reactions in the study group and control group was 11.5% (6/52) and 7.8% (4/51), respectively, with no statistically significant difference (χ²=0.40, P=0.527). Conclusion: High-voltage pulse radiofrequency combined with pregabalin can significantly improve the pain and sleep quality of patients with severe thoracic PHN and reduce the level of pain factors, with a high safety profile.