Electroencephalography biomarkers in Huntington's disease: A systematic review of resting-state and sleep EEG alterations.

OBJECTIVE

To systematically review EEG-based biomarkers in Huntington's disease across resting-state, sleep, medication response, and clinical correlation studies.

METHODS

PubMed, Web of Science, and EMBASE databases were systematically searched for studies of sufficient methodological quality that examined EEG alterations in patients with HD or presymptomatic gene carriers (pre-HD).

RESULTS

A total of 23 studies were included and categorized into resting-state EEG (n = 20), sleep EEG (n = 6), medication-related EEG (n = 3), and clinical correlation studies (n = 20). Resting-state EEG commonly showed reduced alpha and delta power in HD patients. Results for theta and beta band powers were more variable. Sleep EEG studies showed reduced theta power. Except for higher spindle density in unmedicated patients in one study, EEG was not significantly influenced by medications. Lastly, greater impairment in cognitive and motor function was associated with reduced alpha and theta power.

CONCLUSION

The observed alterations in spectral power and sleep EEG are helpful for understanding the neurophysiology of the disease. In order to investigate the potential of EEG as a tool for HD, further research with large sample sizes and standardized methods is needed.

SIGNIFICANCE: This review highlights EEG as a promising, non-invasive biomarker for Huntington's disease, with potential for clinical translation.