Quantitative analysis of the resting-state EEG power spectrum in patients with epilepsy comorbid with anxiety and depression.

Background: Epilepsy is one of the common clinical disorders with comorbid anxiety and depression that severely affects their quality of life and increases their suicidality, while screening for anxiety and depression currently lacks objective identifiers. This study aimed to analyze the characteristics of the electroencephalogram (EEG) power spectrum in patients with epilepsy with comorbid anxiety and depression, utilizing resting EEG data.

Methods: Resting EEG data were collected under standard conditions from two groups: patients with epilepsy comorbid with anxiety and depression (n = 42) and patients without comorbidities (n = 45). EEG power was calculated using data processing with EEGLAB and MATLAB. This study compared the absolute and relative powers of the δ, θ, α, β, and γ frequency bands, as well as the values of (δ + θ)/(α + β), between the two groups. Additionally, the correlation between the EEG power of each frequency band and anxiety and depression scores was analyzed.

Results: 1) Among individuals with epilepsy comorbid with anxiety and depression, lower absolute power of δ, α, and θ at specific sites was observed (P < 0.05), along with lower relative power of θ at certain sites (P < 0.05). Conversely, higher relative power of β and γ at specific sites was noted in those with comorbidities (P < 0.05). 2) There was no statistically significant difference in the values of (δ + θ)/(α + β) between the two groups (P > 0.05). 3) Depression scores exhibited a negative correlation with θ absolute power at the T3 and T4 sites (P < 0.05), while showing a positive correlation with β relative power at the C4 and T6 sites (P < 0.05). Anxiety scores displayed a positive correlation with β relative power at the F4, C3, C4 and T6 sites and γ relative power at F8 site (P < 0.05).

Conclusions: The findings suggest that comorbid anxiety and depression may impact resting EEG power spectra in individuals with epilepsy, particularly in regions exhibiting altered network connectivity. Furthermore, a positive correlation was observed between anxiety and depression scores and β relative power in the right central and right posterior temporal regions, indicating potential screening utility.