Serum ITGAM, CX3CR1, and iNOS Early Post-Op Correlate with Postoperative Cognitive Dysfunction in Elderly Cardiac Surgery Patients

This study aims to investigate the relationship between serum levels of integrin alpha M (ITGAM), CX3CR1, and inducible nitric oxide synthase (iNOS) (microglial activation markers) and the development and severity of postoperative cognitive dysfunction (POCD) in elderly patients undergoing cardiopulmonary bypass (CPB). This observational study included 246 patients aged 60–80 years undergoing CPB. Serum levels of ITGAM, CX3CR1, and iNOS were measured preoperatively and early postoperatively (within 6 hours after surgery). Cognitive function was assessed preoperatively and 7 days postoperatively using the Montreal Cognitive Assessment and a comprehensive battery of neuropsychological tests. Receiver operating characteristic (ROC) analysis was employed to evaluate the predictive value of the biomarkers. Among the participants, 94 patients developed POCD, while 152 did not. Patients with POCD exhibited significantly higher early postoperative serum levels of ITGAM, CX3CR1, and iNOS compared to non-POCD patients. ROC analysis indicated moderate predictive accuracy for each biomarker individually (AUC: ITGAM = 0.78, CX3CR1 = 0.72, iNOS = 0.74), with a notable improvement when biomarkers were combined (AUC = 0.87). MoCA scores at 7 days postoperatively showed significant negative correlations with biomarker levels, while positive correlations were observed between biomarker levels and serum neuron-specific enolase, a marker of neuronal injury. Elevated postoperative serum levels of ITGAM, CX3CR1, and iNOS are strongly associated with the development and severity of POCD in elderly patients undergoing CPB. These biomarkers show promise as predictive tools for early identification of at-risk patients and may represent potential therapeutic targets for mitigating POCD by modulating microglial activation.