Cognition-enhancement effect of median nerve electrical stimulation in patients with cognitive impairment: A retrospective cohort study

Abstract Background People with cognitive impairment often face quality of life problems and require ongoing support, which has profound consequences for caregivers and society. Non-invasive brain stimulation techniques, such as median nerve electrical stimulation (MNS), have shown promising potentials in improving cognitive ability in patients with cognitive impairment. Therefore, we aimed to investigate the efficacy and safety of MNS in cognitive impairment. Methods Patients diagnosed with cognitive impairment from the hospital record management system of the First Affiliated Hospital of Nanchang University from April 1, 2020 to December 31, 2022 were enrolled. Data on patients’ basic characteristics, treatment records, and examination results such as the Mini-Mental State Examination (MMSE), activities of daily living (ADL), and P300 event-related potential before and after treatment were collected. Results Overall, 146 patients with cognitive impairment were enrolled, including 71 patients who underwent conventional therapy (standard treatment group) and 75 patients who underwent conventional therapy and MNS preformation (active MNS group). Before treatment, there were no differences between the standard treatment and active MNS groups in terms of age, sex, etiology, duration of symptoms before therapy, hospital stay, whether they had undergone surgery, MMSE score, ADL score, and amplitude and latency of the P300 event-related potential ( P > 0.05). After treatment, we observed significant improvements in the MMSE score, ADL score, amplitude of P300, and decreased latency of P300 event-related potentials in both groups compared with before treatment ( P < 0.05). In addition, we observed that the active MNS group showed higher MMSE and ADL scores, higher amplitude of P300 event-related potential, and lower latency of P300 event-related potential than the standard treatment group after treatment ( P < 0.05). Furthermore, no side effects were associated with MNS preformation. Conclusion These preliminary data provide early evidence that MNS may be an effective and safe method for promoting the recovery of cognitive ability in patients with cognitive impairment.