The Relationship between C-reactive Protein/Albumin Ratio and Cerebral Infarction Complicated with Pulmonary Infection in Elderly Patients and Its Prognostic Value

YANG Xiaojun; CHEN Shuo; XU Xuhui; ZHOU Qingkun; HAN Li; WANG Jialin; LIU Yan

doi:10.3639/j.issn.2095-3097.2025.03.015

Abstract：Objective To analyze the relationship between C-reactive protein/albumin ratio(CRP/ALB)and pulmonary infection in elderly patients with cerebral infarction and its prognostic value.Methods A retrospective analysis was conducted on 380 elderly patients with cerebral infarction admitted to our hospital from January 2021 to December 2023,and the patients were divided into lung infection group(n=122)and non-infection group(n=258)based on hospital-acquired infection status.The patients with cerebral infarction combined with pulmonary infection were divided into poor prognosis group(n=30)and good prognosis group(n=92)according to the prognosis at 6 months after treatment.Serum C-reactive protein(CRP)and albumin(ALB)levels were detected in all subjects after admission,and CRP/ALB ratio was calculated.The value of CRP/ALB ratio in the prognosis of elderly patients with cerebral infarction combined with pulmonary infection was analyzed by receiver operating characteristic(ROC)curve.Meanwhile,the risk factors of prognosis in elderly patients were explored by multi-factor logistics regression analysis.Results The National Institutes of Health Stroke Scale(NIHSS)score,serum CRP and CRP/ALB ratio in pulmonary infection group were higher than those in non-infection group,and the ALB level was lower than that in non-infection group(P<0.05).The NIHSS score,serum CRP and CRP/ALB ratio in the poor prognosis group were higher than those in the good prognosis group,and the ALB level was lower than that in the good prognosis group(P<0.05).ROC curve results showed that the AUC of serum CRP and ALB in predicting the prognosis of elderly patients with cerebral infarction combined with pulmonary in-fection were 0.804(95%CI:0.754-0.854)and 0.851(95%CI:0.801-0.901),respectively.CRP/ALB ratio predicted the prognosis of elderly patients with cerebral infarction combined with pulmonary infection,and the AUC was 0.905(95%CI:0.855-0.955).Multivariate regression analysis showed that CRP>30.33 mg/L(OR=3.047,95%CI:1.732-5.357),ALB≤28.96 g/L(OR=2.776,95%CI:1.687-4.567),CRP/ALB ratio>1.28(OR=4.225,95%CI:2.078-8.589)were risk factors for prognosis in elderly patients with cerebral infarction combined with pulmonary infection(P<0.05).Conclusion CRP/ALB is abnormally elevated in elderly patients with cerebral infarction complicated with pulmonary infection,and is closely related to prognosis,which is expected to be an effective biological indicator to evaluate the prognosis of patients.