Cognitive Changes in Metabolic Syndrome: A Narrative Review of Neuroimaging Evidence and Molecular Pathway
Abstract
Background: Metabolic syndrome (MetS) is associated with a higher risk of cognitive dysfunction and brain structural alterations, yet the specific contributions of its components and underlying mechanisms remain unclear.
Methods: This narrative review integrates findings from neuroimaging, clinical, and molecular studies to provide a conceptual understanding of how MetS affects cognition. A non-systematic and targeted search was conducted up to June 2025 using terms such as metabolic syndrome, cognition, and magnetic resonance imaging (MRI). Studies were selected based on their relevance and conceptual contribution.
Results: Evidence converges on inflammation, oxidative stress, vascular injury, and insulin resistance as key mechanisms linking MetS to gray and white matter changes and cognitive impairment. Structural and functional MRI studies demonstrate disrupted brain connectivity and reduced hippocampal volume in individuals with MetS. Gender and genetic differences may also influence the strength of this association. The coexistence of metabolic syndrome and cognitive dysfunction is linked to reduced health-related quality of life.
Conclusion: The narrative synthesis highlights how metabolic and vascular factors jointly drive neurocognitive decline and underscores the need for longitudinal and mechanistic research