Plasma Amyloid-β 1-40 and Postoperative Delirium After Cardiac Surgery

Area of Science:

• Neuroscience
• Cardiology
• Biomarker Research

Background:

• Postoperative delirium (POD) is a common and severe complication following cardiac surgery, increasing dementia risk and adverse outcomes.
• Early identification of patients at high risk for POD remains a significant clinical challenge.

Purpose of the Study:

• To investigate the association between preoperative plasma Alzheimer disease biomarkers and baseline cognition.
• To determine if these biomarkers can independently predict POD in patients undergoing elective cardiac surgery.

Main Methods:

• Prospective observational cohort study (FINDERI) of 504 patients aged 50+ undergoing elective cardiac surgery.
• Preoperative plasma levels of amyloid-beta 1-40 (Aβ1-40), Aβ1-42, phosphorylated tau 181 (pTau181), and pTau217 were measured.
• Postoperative delirium (POD) assessed daily using the Confusion Assessment Method; baseline cognition assessed with Montreal Cognitive Assessment (MoCA).

Main Results:

• Patients who developed POD had higher preoperative Aβ1-40 and pTau217 levels.
• Aβ1-40 was the strongest independent biomarker associated with POD risk (AUC, 0.65).
• Combining biomarkers with clinical factors and MoCA scores improved POD risk prediction (AUC, 0.77).

Conclusions:

• Preoperative plasma Aβ1-40 is strongly associated with POD risk in cardiac surgery patients.
• Aβ1-40 may aid in stratifying POD risk, but further validation is needed for clinical utility.