Mechanistic study of Alzheimer's disease with behavioral and psychological symptoms based on electroencephalography microstates

BackgroundBehavioral and psychological symptoms of dementia (BPSD) are common in Alzheimer's disease (AD), yet their mechanisms remain unclear.ObjectiveWe aim to explore the possible neurophysiological mechanisms of BPSD using high temporal resolution electroencephalography (EEG) microstate technology, laying the foundation for clinical evaluation and subsequent treatment.MethodsWe enrolled 52 AD patients (25 with BPSD, 27 without) and 29 age- and gender-matched healthy controls (HC). All participants underwent various neuropsychological assessments and resting-state EEG recordings. Resting-state EEG data were analyzed employing microstate analysis techniques, with a focus on four key microstate parameters: duration, occurrence, coverage, and transition probability. Inter-group comparisons were performed using post-hoc tests, with statistical significance determined through False Discovery Rate (FDR) correction. Furthermore, the correlations between the indicators and neuropsychological assessment scores were analyzed.ResultsCompared to the HC and non-BPSD groups, the BPSD group showed an increase in the transition rate from microstate A to microstate C. Compared to the HC group, the BPSD group showed an extension in the duration of microstate A and a decrease in the frequency of microstate D. Compared to the HC group, the non-BPSD group showed prolonged durations (A, B, mean) and reduced occurrences (C, D, mean).The partial correlation analysis with years of education as a covariate showed that in the BPSD group, the duration of microstate A was correlated with the severity of the Neuropsychiatric Inventory (NPI) and the Hamilton Anxiety Scale (HAMA).ConclusionsAD with and without BPSD exhibits different altered brain dynamics.