Bingbing Meng,1,2,* Kai Zhang,1,2,* Chang Liu,2,3 Siyi Yao,1,2 Zhao Li,1,2 Jingsheng Lou,1,2 Qiang Fu,1,2 Yanhong Liu,1,2 Jiangbei Cao,1,2 Weidong Mi,1,2,4 Hao Li1,2,4 

1Medical School of Chinese People’s Liberation Army (PLA), Beijing, People’s Republic of China; 2Department of Anesthesiology, The First Medical Center, Chinese People’s Liberation Army General Hospital (PLAGH), Beijing, People’s Republic of China; 3Nankai University, Tianjing, People’s Republic of China; 4National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Beijing, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Weidong Mi; Hao Li, Department of Anesthesiology, The First Medical Center, Chinese People’s Liberation Army General Hospital (PLAGH), 28th Fuxing Road, Haidian District, Beijing, 100853, People’s Republic of China, Email wwdd1962@aliyun.com; lihao301@126.com

Objective: To identify the association between preoperative inflammatory state and myocardial injury after noncardiac surgery (MINS) in older patients using systemic inflammation indicators neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) and to compare their clinical predictive values.
Methods: This study included patients aged ≥ 65 years who underwent noncardiac surgery between January 2017 and August 2019. The relationship between preoperative inflammatory state and MINS was investigated using univariate and multivariate logistic regression analyses. The predictive values of NLR, PLR, and SII were determined by receiver operating characteristic (ROC) curve analysis. Based on the basic model we constructed, the predictive values were compared through separately adding NLR, PLR and SII.
Results: Among 12464 patients, 965 (7.74%) developed MINS. The optimal cut-off values of NLR, PLR, and SII were 597× 109, 2.59, and 923. Univariate and multivariate analyses show that preoperative inflammatory state is associated with MINS. In the multivariate analysis, the OR values for NLR, PLR, and SII were (OR: 1.61, 95% CI: 1.36– 1.89, p< 0.001), (OR: 1.28, 95% CI: 1.07– 1.52, p=0.006), and (OR: 1.43, 95% CI: 1.20– 1.70, p< 0.001). ROC curve analysis indicated that NLR was more predictive of MINS (area under the curve [AUC]: 0.671, 95% CI: 0.652– 0.689) than PLR (AUC: 0.635, 95% CI: 0.616– 0.655) and SII (AUC: 0.648, 95% CI: 0.628– 0.667). The addition of the NLR to a basic prediction model improved its predictive ability to a greater extent than the addition of PLR and SII.
Conclusion: Higher preoperative inflammation levels are associated with an increased risk of MINS. The NLR, PLR, and SII are independent risk factors for MINS and NLR demonstrated better predictive value than that of PLR and SII.

Keywords: neutrophil-to-lymphocyte ratio, NLR, platelet-to-lymphocyte ratio, PLR, systemic, immune, inflammation index, SII, myocardial injury after noncardiac surgery, MINS