SYSTEMIC INFLAMMATION AND COGNITIVE DECLINE: A SYSTEMATIC REVIEW OF NEUROINFLAMMATORY BIOMARKERS IN CHRONIC DISEASES
DOI:
https://doi.org/10.56238/levv17n59-028Keywords:
Inflammation, Cognitive Dysfunction, Biomarkers, Chronic DiseaseAbstract
Introduction: Systemic inflammation has been increasingly recognized as a central contributor to cognitive decline across multiple chronic diseases, involving complex interactions between peripheral immune activation and central nervous system dysfunction.
Objective: The primary objective of this systematic review was to evaluate the association between systemic inflammation and cognitive decline through the analysis of neuroinflammatory biomarkers in chronic diseases. Secondary objectives included identifying key biomarkers, assessing consistency of associations, evaluating methodological heterogeneity, exploring underlying mechanisms, and determining clinical applicability.
Methods: A systematic search was conducted in PubMed, Scopus, Web of Science, Cochrane Library, LILACS, ClinicalTrials.gov, and ICTRP. Inclusion criteria comprised studies published within the last five years involving human participants with chronic diseases and reporting associations between inflammatory biomarkers and cognitive outcomes. Study selection and data extraction were performed independently by two reviewers. Risk of bias was assessed using RoB 2, ROBINS-I, and QUADAS-2, and certainty of evidence was evaluated using GRADE.
Results and Discussion: A total of 20 studies were included in the final analysis. Evidence consistently demonstrated that both traditional inflammatory markers, such as interleukin-6 and C-reactive protein, and emerging biomarkers, including neurofilament light chain and glial fibrillary acidic protein, are associated with cognitive decline across diverse chronic conditions. Findings also highlighted disease-specific mechanisms, sex differences, and the relevance of vascular and metabolic pathways.
Conclusion: Neuroinflammatory biomarkers represent promising tools for early detection, risk stratification, and monitoring of cognitive decline in chronic diseases. However, heterogeneity among studies and the predominance of observational designs underscore the need for standardized methodologies and longitudinal validation to support clinical implementation.
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References
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