Abstract: Background Acute myocardial infarction（AMI） poses a significant threat to the health and quality of life of the elderly. Previous studies have found that low-density lipoprotein cholesterol（LDL-C） is an independent risk factor for AMI，and increased uric acid and decreased high-density lipoprotein cholesterol are also associated with AMI. Objective To investigate the predictive value of cumulative LDL-C exposure，UHR，and their combination on the occurrence of AMI in the elderly. Methods A retrospective study was conducted on 737 elderly patients diagnosed with AMI at Northern Jiangsu People's Hospital from January 2019 to December 2023（experimental group） and 260 elderly patients admitted during the same period who were excluded from the AMI diagnosis（control group）. Patient demographics and laboratory test results were collected，and cumulative LDL-C exposure and UHR values were calculated. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for AMI in the elderly. Receiver operating characteristic（ROC） curves were plotted for cumulative LDL-C exposure，UHR，and their combined prediction of AMI in the elderly，and the area under the ROC curve（AUC） was calculated to assess the predictive efficacy of cumulative LDL-C exposure，UHR，and their combination for AMI in the elderly. Results The characteristics of male gender，smoking history，alcohol abuse history，history of hypertension，history of type 2 diabetes，BMI，glycated hemoglobin A1c，white blood cell count，neutrophil count，monocyte count，triglycerides，total cholesterol，HDL-C，LDL-C，lipoprotein a，uric acid，cumulative LDL-C exposure，UHR，apolipoprotein A1，and albumin of the experimental group were compared with the control group，results showed statistically significant differences（P<0.05）. Results of multivariate Logistic regression analysis showed that male gender（OR=3.026，95%CI=1.769-5.178，P<0.001），history of type 2 diabetes（OR=4.834，95%CI=2.882-8.109，P<0.001），and high level of white blood cell count（OR=1.580，95%CI=1.368–1.825，P<0.001），LDL-C（OR=3.801，95%CI=2.712-5.327，P<0.001），cumulative LDL-C exposure（OR=1.898，95%CI=1.042-3.457，P=0.036），UHR（OR=10.658，95%CI=5.147-22.069，P<0.001） were independent risk factors for AMI in the elderly，while high level of HDL-C（OR=0.426，95%CI=0.184-0.986，P=0.046） and albumin（OR=0.989，95%CI=0.979-0.999，P=0.031） were independent protective factors. ROC curve results showed that the AUC for predicting occurrence of AMI in the elderly based on cumulative LDL-C exposure and UHR was 0.726（95%CI=0.691-0.761） and 0.700（95%CI=0.663-0.737），respectively，with sensitivities of 0.696 and 0.742，specificities of 0.650 and 0.607，and cutoff values of 214.86 and 317.06，respectively. The combined AUC was 0.813（95%CI=0.784-0.842），with a sensitivity of 0.723 and a specificity of 0.730. Conclusion History of type 2 diabetes mellitus and high level of leukocytes counts，LDL-C，cumulative LDL-C，UHR are independent risk factors for AMI in the elderly，high level of HDL-C and albumin are independent protective factors. Cumulative LDL-C exposure，UHR and the combination of the two can be used as early biomarkers to effectively identify the occurrence of AMI in the elderly.

Key words: Acute myocardial infarction, Cumulative low-density lipoprotein cholesterol exposure, Uric acid to highdensity lipoprotein cholesterol ratio, Elderly, Risk assessment

摘要： 背景 急性心肌梗死（AMI）极大威胁着老年人的健康与生存质量，既往研究发现低密度脂蛋白胆固醇（LDL-C）是AMI的独立危险因素，尿酸的增多与高密度脂蛋白胆固醇（HDL-C）的减少以及AMI相关。然而累积LDL-C暴露量、尿酸/HDL-C比值（UHR）和老年AMI发生的相关性研究较少。目的 探究累积LDL-C暴露量、UHR及两者联合对老年AMI发生的预测价值。方法 回顾性纳入苏北人民医院2019年1月—2023年12月诊断为AMI的737例老年患者（试验组）和同期入院并排除AMI的260例老年患者（对照组）为研究对象。收集患者一般资料及实验室检查指标，计算累积LDL-C暴露量和UHR值。采用单因素及多因素Logistic回归分析筛选老年AMI发生的独立危险因素。绘制累积LDL-C暴露量、UHR及两者联合预测老年AMI发生的受试者工作特征（ROC）曲线，并计算ROC曲线下面积（AUC），评估累积LDL-C暴露量、UHR及两者联合对老年AMI发生的预测效能。结果 试验组性别、吸烟史、酗酒史、高血压病史、2型糖尿病史、BMI、糖化血红蛋白A1c、白细胞计数、中性粒细胞计数、单核细胞计数、三酰甘油、总胆固醇、HDL-C、LDL-C、脂蛋白a、尿酸、累积LDL-C暴露量、UHR、载脂蛋白A1、白蛋白与对照组比较，差异均有统计学意义（P<0.05）。多因素Logistic回归分析结果显示，男性（OR=3.026，95%CI=1.769~5.178，P<0.001）、2型糖尿病史（OR=4.834，95%CI=2.882~8.109，P<0.001）以及高水平的白细胞计数（OR=1.580，95%CI=1.368~1.825，P<0.001）、LDL-C（OR=3.801，95%CI=2.712~5.327，P<0.001）、累积LDL-C暴露量（OR=1.898，95%CI=1.042~3.457，P=0.036）和UHR（OR=10.658，95%CI=5.147~22.069，P<0.001）是发生老年AMI的独立危险因素，高水平的HDL-C（OR=0.426，95%CI=0.184~0.986，P=0.046）和白蛋白（OR=0.989，95%CI=0.979~0.999，P=0.031）为独立保护因素。ROC曲线结果显示，累积LDL-C暴露量和UHR预测老年AMI发生的AUC分别是0.726（95%CI=0.691-0.761）和0.700（95%CI=0.663-0.737），灵敏度分别为0.696和0.742，特异度分别为0.650和0.607，截断值分别为214.86和317.06。两者联合的AUC为0.813（95%CI=0.784-0.842），灵敏度为0.723，特异度为0.730。结论 2型糖尿病史和高水平的白细胞计数、LDL-C、累积LDL-C以及UHR为发生老年AMI的独立危险因素，高水平的HDL-C和白蛋白为独立保护因素；累积LDL-C、UHR及两者联合均可作为有效识别老年AMI发生的早期生物标志物。

关键词: 急性心肌梗死, 累积低密度脂蛋白胆固醇暴露量, 尿酸与高密度脂蛋白胆固醇比值, 老年, 风险评估