Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Postoperative Cognitive Dysfunction in Older Patients: A Randomized Controlled Clinical Trial

Shuqin Li; Jiale Song; Xiao Xiao; Qinghe Zhou; Shulei Zhang; Jian Lu

doi:10.1016/j.neurom.2026.04.004

Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Postoperative Cognitive Dysfunction in Older Patients: A Randomized Controlled Clinical Trial

Neuromodulation. 2026 Jun;29(4):660-666. doi: 10.1016/j.neurom.2026.04.004. Epub 2026 Apr 17.

Authors

Shuqin Li¹, Jiale Song², Xiao Xiao², Qinghe Zhou², Shulei Zhang², Jian Lu³

Affiliations

¹ Jiaxing University Master Degree Cultivation Base, Zhejiang Chinese Medical University, Hangzhou City, Zhejiang Province, China; Department of Anesthesiology, The Second Hospital of Jiaxing, The Second Affiliated Hospital of Jiaxing University, Jiaxing City, Zhejiang Province, China.
² Department of Anesthesiology, The Second Hospital of Jiaxing, The Second Affiliated Hospital of Jiaxing University, Jiaxing City, Zhejiang Province, China.
³ Department of Anesthesiology, The Second Hospital of Jiaxing, The Second Affiliated Hospital of Jiaxing University, Jiaxing City, Zhejiang Province, China. Electronic address: ljp200681@163.com.

PMID: 42104979
DOI: 10.1016/j.neurom.2026.04.004

Abstract

Objectives: The aim of this study was to investigate the effect of transauricular vagus nerve stimulation (taVNS) on early postoperative cognitive dysfunction (POCD) in older patients and further explore the mechanism by which vagus nerve stimulation improves postoperative cognitive function.

Materials and methods: A total of 103 patients undergoing elective surgery for gastrointestinal tumors were selected and randomly assigned to the taVNS group (n = 49) or the sham taVNS (sham) group (n = 52), receiving auricular vagal nerve stimulation or sham stimulation therapy (once daily for 30 minutes, 4/20 Hz, 0.8-1.5 mA or 0 mA) on preoperative day 1 and on postoperative day (POD) 1, POD2, POD3, and POD4. The primary outcome was the cognitive function assessed by Montreal Cognitive Assessment on preoperative day 1 and on POD1, POD3, and POD7. The secondary study indicators were postoperative nausea and vomiting (PONV), postoperative delirium, postoperative sleep quality, perioperative changes in S100 calcium binding protein beta (S100β) and interleukin 6 (IL-6), and postoperative pain intensity.

Results: The incidence of POCD in the taVNS group was significantly lower than that in the sham group (10.2% vs 32.7%, χ² = 7.498, p = 0.006). The plasma levels of S100β and IL-6 in the taVNS group were significantly lower than those in the sham group on one to two days after surgery (F = 5.687, p = 0.018; F = 10.96, p = 0.001). The incidence of PONV in the taVNS group was significantly lower than that in the sham group (χ² = 5.73, p = 0.017). There was no significant difference in postoperative sleep quality, postoperative pain intensity, and the occurrence of POD between the two groups (p > 0.05).

Conclusions: taVNS can reduce the incidence of POCD in older patients and may improve cognitive function by suppressing the inflammatory response.

Clinical trial registration: The clinical trial registration number for the study is ChiCTR2500115495 (Chinese Clinical Trial Register, December 26, 2025-retrospectively registered; https://www.chictr.org.cn/bin/project/edit?pid=292929).

Keywords: Acupoint stimulation; inflammation; postoperative cognitive impairment; vagus nerve stimulation.

Publication types

Randomized Controlled Trial

MeSH terms

Aged
Aged, 80 and over
Double-Blind Method
Female
Humans
Male
Middle Aged
Postoperative Cognitive Complications* / psychology
Postoperative Cognitive Complications* / therapy
Postoperative Complications* / therapy
Transcutaneous Electric Nerve Stimulation* / methods
Treatment Outcome
Vagus Nerve Stimulation* / methods