Electrophysiological disruptions and cerebrospinal fluid biomarkers in mild cognitive impairment patients

Abstract

AbstractBackgroundAlzheimer's Disease (AD) is a progressive neurodegenerative disorder characterized, at the neuropathological level, by the accumulation of amyloid‐β (Aβ) neuritic plaques and neurofibrillary tangles formed by hyperphosphorylated tau protein. A key aspect of AD’s is focused on its early detection. In recent years, cerebrospinal fluid (CSF) has been established as a sensible and validated biomarker that could help to provide an accurate diagnosis of the disease. It is known that lower CSF Aβ‐42 concentrations and higher CSF levels of total and phosphorylated tau (t‐tau and p‐tau respectively), have been extensively replicated parameters among AD patients. Similarly, electrophysiological signatures, as analyzed by the electroencephalography (EEG) technique, seem to be a non‐invasive useful tool for evaluating the progressive loss of efficiency of neuronal networks. Given that, the purpose of this study was to explore the correlation between power EEG values derived from clusters of sensors and CSF markers in a sample of mild cognitive impairment (MCI) patients.Method7 MCI participants (aged from 61 to 85) were recruited from the Cognitive Disorders Unit of the Hospital Universitari Santa Maria (Lleida, Spain). All of them underwent a neuropsychological evaluation, CSF lumbar puncture, and EEG recordings.ResultAmyloid. Male population showed a significant negative correlation (rho = ‐0.754, p < 0.003) between amyloid load and theta power in antero‐posterior regions of the brain. The average power of the cluster correlated significatively with ADAS (rho = 0.562, p < 0.037), total tau (rho = 0.538, p < 0.049) and delayed recall (rho = ‐0.612, p < 0.020). Total tau. A widespread alpha power cluster was found in the male population whose oscillatory activity correlated negatively with t‐tau CSF load (rho = ‐0.653, p < 0.014). When assessing the female population, we found a relationship (rho = ‐0.864, p < 0.001) between total‐tau and beta power in a widespread cluster. Additionally, the beta cluster average power significatively correlated with p‐tau load (rho = ‐0.800, p < 0.005) and age (rho = ‐0.621, p < 0.041).ConclusionElectrophysiological activity seems to be depicting a clear sex‐based pattern of associations with neuropathological markers of AD.