Delirium, a severe neuropsychiatric syndrome affecting elderly patients in medical settings, varies in incidence based on treatment and intervention types. This systematic review aims to identify suitable biomarkers (hormones, neurotransmitters, and neuroinflammatory markers) to comprehend delirium’s origins, predict pre-operative risks, and detect early onset. Biomarkers play a pivotal role in assessing delirium and its risk.
The review involved comprehensive searches across databases (MEDLINE, EMBASE, Cochrane Library, Web of Science, Scopus). Among 2513 articles, 32 were selected for analysis.
Validation of biomarkers’ accuracy is challenging due to potential inflammation-related elevation. Also, their affordability remains unexplored.
Elevated cortisol relates to dementia and delirium risk, yet evidence is inconclusive. Disrupted cholinergic activity and increased anticholinergic levels contribute to delirium. Tau protein links to delirium, while IL-6 elevation, especially pre-operatively, associates with post-op delirium. Higher TNF-α levels appear in post-op delirium. Elevated CRP, tied to inflammation, and pre-op CRP associate with delayed delirium.
This review underscores links between neuroinflammation biomarkers (CRP, IL-6, TNF-α) and delirium risk. Further research is needed to standardize methodologies for practical clinical use.