Abstract:Objective To analyze the effects of red blood cell distribution width (RDW) and gamma-glutamyltransferase (GGT) on the prognosis of the advanced aged patients with coronary heart disease (CHD) complicated with pulmonary infection. Methods A retrospective analysis was made of the clinical data of 256 elderly CHD patients (age>80 years) complicated with pulmonary infection admitted to Xijing Hospital Affiliated to the Air Force Medical University from January 2018 to January 2021. According to the clinical prognosis, they were divided into the good prognosis group (n=192) and the poor prognosis group (n=64), and binary multivariate logistic regression was performed to analyze the prognostic factors. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of RDW, GGT and their combined predictors in the elderly CHD patients with pulmonary infection. SPSS 19.0 was used for data analysis, and depending on data type, independent sample t -test, Mann-Whitney U test or Chi-square test for the comparison between two groups. Results The poor prognosis group was significantly higher than the good prognosis group in age, neutrophil-to-lymphocyte ratio, N-terminal pro-B type natriuretic peptide, creatinine, procalcitonin, mean arterial pressure, RDW, and GGT, the differences being statistically significant (P < 0.05 for all). Binary multivariate logistic regression analysis showed that RDW (OR=4.167,95%CI 1.579-10.995; P=0.004) and GGT (OR=1.011,95%CI 1.001-1.021; P=0.039) were independent risk factors for poor prognosis in the elderly CHD patients complicated with pulmonary infection. The area under ROC curve (AUC) of RDW for the prognosis was 0.824 with a cut-off value of 15.15, a sensitivity of 82.5%, and a specificity of 81.3%. The AUC of GGT for prognosis was 0.748 with a cut-off value of 40.15,a sensitivity of 87.5%, and a specificity of 67.5%. The AUC of the combined predictors was 0.860 with a cut-off value of 0.239, a sensitivity of 81.3%, and a specificity of 80.4%. Conclusion The elderly CHD patients complicated with pulmonary infection are prone to have a poor prognosis because of their atypical symptoms and insidious onset. RDW or GGT can be used as one of the indicators to predict their poor prognosis.