The Predictive Role Of Age-adjusted Charlson Comorbidity Index In Postoperative Delirium In The Elderly Following Thoracic And Abdominal Surgery

Objective This study aimed to explore the connection between age-adjusted Charlson comorbidity index(ACCI)and postoperative delirium(POD),and to determine the predictive role of ACCI in POD in geriatric patients undergoing thoracic and abdominal surgery.Methods This study included 185 elderly patients who scheduled for thoracic and abdominal surgery at Hebei General Hospital from October2021 to May 2022.Mini-mental state examination(MMSE)was used to evaluate the cognitive status of the patients before surgery,preoperative and postoperative pain was measured by visual analog scale(VAS),and POD was assessed via confusion assessment method(CAM)during the first 3 days after surgery,and the patients were eventually classified into delirium group(group D)and non-delirium group(group N).Basic,and clinical data from all patients were collected,and ACCI was calculated.Univariate and multivariate logistic regression analysis were adopted to investigate the role of ACCI and other variables in POD.The predictive value of related risk factors for POD was further evaluated via the characteristic curve of receiver operating characteristic(ROC),and the cut-off value for each variable to predict POD was determined.Results1 Comparison of basic and perioperative data between two groups:POD was diagnosed in 36 of 184 patients included in our study.There were statistic differences in age(P=0.004),educational level(P=0.022),American Society of Anesthesiologists(ASA)grade(P=0.004),body mass index(BMI)(P=0.028),preoperative MMSE scores(P=0.010),ACCI(P<0.001)and pain scores in the first 3 days after surgery(P<0.05)between two groups.2 Comparison of preoperative laboratory relevant indicators between two groups: Compared to those without POD,subjects with POD had lower levels of preoperative albumin(36.0 ± 5.5 vs 38.0 ± 4.8,P=0.030),albumin to fibrinogen ratio(AFR)(10.5(8.6,13.6)vs 12.7(9.9,14.9),P=0.026)and total cholesterol(4.3(3.7,4.9)vs 4.8(3.9,5.5),P=0.037),but patients with a higher level of D-dimer had an increased risk to develop POD(P=0.009).3 The univariate logistic regression analysis showed: The outcomes that differed significantly between two groups were age,ASA grade,BMI,preoperative MMSE scores,ACCI,preoperative albumin,preoperative AFR,preoperative D-dimer and pain scores within the postoperative first 3days(all P<0.05).The results by multivariate logistic regression analysis indicated: ACCI(OR:1.834;95% CI:1.434～2.344;P<0.001),preoperative MMSE scores(OR:0.873;95%CI:0.767～0.994;P=0.040),preoperative albumin(OR:0.909;95%CI:0.826～1.000;P=0.049)and postoperative pain(OR:2.013;95%CI:1.459～2.778;P<0.001)were the independent risk factors for POD.4 Multicollinearity among variables by linear analysis: There was no significant collinearity among variables included in multivariate logistic regression analysis(all Tol>0.1,VIF<10).5 The outcomes by ROC curve demonstrated: ACCI can predict POD more accurately with the largest area under curve of 0.794,sensitivity of0.861 and the cut-off value of 5.5,respectively,compared with other risk factors.ConclusionPOD is a common postoperative complication in the elderly following thoracic and abdominal surgery,and ACCI may early predict the risk of POD.