A Multimodal Neuroimaging Study of Hyperlipidemia-Induced Abnormal Spontaneous Brain Activity and Cognitive Decline

To investigate multidomain cognitive performance in older adults with hyperlipidemia and its associations with alterations in spontaneous brain activity and functional connectivity (FC).

A total of 104 participants were recruited, comprising 50 hyperlipidemia patients and 54 healthy controls. Comprehensive psychological assessments were conducted, and resting-state functional magnetic resonance imaging (rs-fMRI) data were collected from both groups. Amplitude of low-frequency fluctuations (ALFF), regional homogeneity (ReHo), and FC were calculated.

Compared with healthy controls, hyperlipidemia patients showed significantly lower SDMT scores (p < 0.001), whereas no significant between-group differences were observed in the other neuropsychological measures. Imaging analyses revealed altered spontaneous brain activity and FC involving frontal, temporal, and cerebellar regions. In exploratory correlation analyses, lower SDMT scores and longer STT-B completion times were associated with higher zALFF values in the right inferior temporal gyrus (r = -0.197, p = 0.046); however, the SDMT association was modest and did not survive correction for multiple comparisons (r = 0.257, p = 0.009). Age also positively correlated with zALFF in this region (r = 0.195, p = 0.048).

Hyperlipidemia was associated with lower SDMT performance, altered spontaneous activity, and functional connectivity in the frontal, temporal, and cerebellar regions. The exploratory associations involving the right inferior temporal gyrus suggest a potential relationship between altered regional brain activity and cognitive performance.