Production of inflammatory cytokines, cortisol, and A beta 1-40 in elderly oral cancer patients with postoperative delirium

Aim: Pathophysiological disorders after surgery might be related to postoperative delirium (POD). This study was designed to elucidate the pathogenesis of POD in elderly oral cancer patients by determining the perioperative kinetics of inflammatory cytokines, cortisol, and amyloid beta 1-40 (A beta 1-40). Methods: A total of 257 elderly oral cancer patients who underwent tumor resection surgery were selected. Venous blood was collected prior to surgery (T0), at the end of surgery (T1), and at 12 hours after surgery (T2). During the first three postoperative days, patients were examined using the confusion assessment method twice a day (8 am and 8 pm). Mini-Mental State Examination scores were recorded at T0 and on postoperative days 1, 3, and 7. Ultimately, 56 patients suffering from POD made up the POD group, and 56 patients randomly selected from a cohort of patients without POD were allocated to the no POD (NPOD) group. Subsequently, interleukin-6, C-reactive protein, procalcitonin, cortisol, and A beta 1-40 in plasma from the two groups were measured. Results: The two groups displayed comparable basic characteristics. There were no differences in all tested biomarkers between the two groups at T0. However, after surgery, the biomarker levels displayed distinct patterns between the two groups. The peak levels of all biomarkers were higher in the POD group than in the NPOD group. Conversely, the Mini-Mental State Examination scores after surgery were lower in the POD group than in the no POD group. Conclusion: The boost of inflammatory cytokines, cortisol, and A beta 1-40 after surgery might be involved in POD onset among elderly oral cancer patients. POD was accompanied by progressive cognitive deficiency.