PhD Scientific Days 2026

Neurosciences

The effects of Alzheimer's disease on the autonomic nervous system

Name of the presenter

Váraljai, Christopher

Institute/workplace of the presenter

Department of Neurointervention and Neurosurgery - Semmelweis University

Authors

Dr. Christopher Váraljai¹
1: Department of Neurointervention and Neurosurgery - Semmelweis University

Text of the abstract

Introduction: Alzheimer's disease (AD) is the most common major neurocognitive disorder. Its symptoms include memory impairment, loss of acquired knowledge and learning ability, and deterioration of behaviour and personality. The neuropathology of the disease suggests that protein aggregates also accumulate in the brain structures involved in the integration of autonomic functions. Since these regions are also affected in the early stages of AD, they may potentially aid in the early detection of the disease by causing measurable symptoms. Very few articles have addressed this possibility to date.
Objective: The aim of our study is to determine whether the symptoms resulting from AK's effects on the autonomic nervous system—HRV and sudomotor sympathetic skin response (SSR) abnormalities—can be used for early diagnosis of the disease and for the differential diagnosis of other major neurocognitive disorders.
Method: We examined 89 patients, 11 of whom were diagnosed with mild cognitive impairment (MCI), 12 with AD, 6 with other major neurocognitive disorders (non-AD), and 60 had no such disease (healthy control, HC). We measured the patients' HRV values using a single-lead ECG called WIWE. We mapped the patients' SSR values using a system called Vitalscan Sudocheck. We evaluated the measured data using JASP 0.18.0.0 statistical software.
Results: Based on ANOVA, there was a significant (p=0.024) difference between the groups in terms of HRV values, and based on an independent sample t-test, there was a significant (p<0.05) difference between the HC and non-AD, and MCI and non-AD groups. In terms of SSR values, ANOVA showed a significant (p<.001) difference between the groups, and an independent sample t-test showed a significant (p<0.05) difference between the HC and MCI populations, the HC and non-AD populations, the MCI and AD populations, and the AD and non-AD populations.
Conclusion: HRV abnormalities worsen during the progression of AD and non-AD. SSR values were lower in the MCI and non-AD populations, while they did not change in AD compared to the control group. Therefore, it is conceivable that MCI patients whose SSR values deteriorated will progress to non-AD, while those whose values did not deteriorate will progress to AD.