Pathophysiology and biomarkers of delirium in older adults-Narrative review.

BACKGROUND

Delirium is a frequent acute neurocognitive syndrome in older adults, associated with morbidity, mortality, and long-term cognitive decline. Its pathophysiology is multifactorial and not yet fully understood.

OBJECTIVE

To summarize clinically relevant concepts of delirium pathophysiology and emerging biomarkers.

METHODS

Narrative review of literature from 2010-2026, prioritizing human studies, reviews, meta-analyses, and clinically relevant pathophysiological literature relevant to older hospitalized or perioperative patients.

RESULTS

Delirium arises from the interaction of predisposing vulnerability and acute triggers. Relevant mechanisms include neuroinflammation, neurotransmitter imbalance, neurodegeneration, metabolic dysfunction and blood-brain barrier impairment. Biomarker research has identified promising candidates, including inflammatory, neurodegenerative, metabolic and stress-related markers but none is currently established for routine clinical use.

CONCLUSION

Delirium prevention remains clinically driven. Multimodal biomarkers may support future risk stratification but require prospective validation.