Neuroinflammatory and Structural Brain Changes Associated with Nonalcoholic Fatty Liver Disease: A Systematic Review
Brain Changes Associated with Nonalcoholic Fatty Liver Disease
Keywords:
Neuroinflammatory, Structural Brain Changes, Nonalcoholic Fatty Liver Disease, Hepatopathology, Meta-Analysis, NAFLDAbstract
Background: Over recent years, physicians have increasingly acknowledged NAFLD as a widespread medical condition with effects that extend beyond liver dysfunction. High-quality research now indicates that NAFLD causes meaningful alterations in brain structure and function, which may be responsible for cognitive decline. Objective: A systematic review with meta-analysis examined the connection between NAFLD and adverse brain outcomes through a focused investigation of imaging data and cognitive performance, and systemic inflammatory markers. Methodology: The study followed methods based on PRISMA 2020 guidelines, conducting a comprehensive search of literature through PubMed, Scopus, and Embase databases. This analysis included observational, preclinical, and MR studies based on ten research publications that made it through the eligibility process. A random-effects model was used to perform meta-analysis. Risk of bias was also assessed using appropriate tools. Results: A moderate but significant effect of NAFLD on brain alterations was found with an effect size of -0.56 points (95% CI -0.68 to -0.45; p < 0.0001). The research found that brain volume was reduced, cortical brain areas diminished, and lower scores on tests of cognitive ability. Both MR and animal studies showed the cause and effect for this inflammation as the middle point. Conclusion: Structural brain changes are caused in research results by NAFLD, thus supporting the liver-brain connection. Clearly, the need for integrated management strategies is for both liver health and brain health.
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Copyright (c) 2025 Ehsan Khan, Sabeeha Saddique, Syeda Maira Gillani, Sidra Anwar, Uday Shree Akkala (Author)
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