Gamma Power and Its Association With Lipid Profile and Cognitive Impairment in Schizophrenia: A Resting-State EEG...

Schizophrenia (SCZ) is characterized by pervasive cognitive impairments and a high prevalence of lipid profile abnormalities. Emerging evidence suggests that these lipid profile disturbances may exacerbate cognitive decline, but the underlying neurophysiological mechanisms remain unclear. This study hypothesizes that SCZ patients with lipid profile abnormalities exhibit distinct cognitive deficits and electroencephalography (EEG) features, particularly in gamma-band activity, which may serve as potential biomarkers for cognitive dysfunction.

In this cross-sectional study, 137 SCZ patients were recruited, including 46 with lipid abnormalities and 91 with normal lipid profiles. Cognitive performance was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and symptom severity was evaluated via Positive and Negative Syndrome Scale. Resting-state EEG data were recorded and analyzed across 5 frequency bands (δ, θ, α, β, and γ).

Schizophrenia patients with lipid profile abnormalities showed significantly lower RBANS total and subdomain scores (especially in visuospatial/constructional ability, attention, and delayed memory). Electroencephalography analysis revealed reduced gamma-band power (30-48 Hz, 52-70 Hz) in these patients, which positively correlated with overall and domain-specific cognitive scores. Multiple regression analyses identified gamma-band power and education level as significant predictors of cognitive performance.

Lipid profile abnormalities in SCZ are associated with exacerbated cognitive impairment and attenuated gamma-band power. Gamma activity may reflect underlying synaptic and network dysfunction related to lipid dysregulation and serve as a promising noninvasive EEG biomarker for cognitive risk stratification in metabolically vulnerable SCZ subgroups.