低密度脂蛋白胆固醇/高密度脂蛋白胆固醇比值预测卒中高危人群无症状颈动脉斑块及其稳定性

Low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio predicts asymptomatic carotid plaques and their stability in high-risk stroke population

目的探讨卒中高危人群低密度脂蛋白胆固醇/高密度脂蛋白胆固醇比值(low-density lipoprotein cholesterol/high-density lipoprotein cholesterol concentration ratio, LHR)与无症状颈动脉斑块及其稳定性的关系。方法自2012年12月至2015年4月采用整群抽样的流行病学调查方法,在连云港市赣榆区海头镇、班庄镇和塔山镇的11个农村社区以及新浦区和海州区的9个城市社区选取≥40岁常住人口39944人为调查对象,排除3个月内服用降脂药以及既往有卒中或短暂性脑缺血发作病史者,最终筛选出卒中高危人群6592人。采用超声检测颈动脉斑块,并将研究对象分为无斑块组和斑块组,后者进一步分为稳定斑块组和不稳定斑块组。采用多变量logistic回归分析评估颈动脉斑块及其稳定性的独立危险因素,并计算优势比(odds ratio, OR)及95%可信区间(confidence interval, CI)。采用受试者工作特征(Receiver Operating Characteristic, ROC)曲线评估LHR对颈动脉斑块的预测效能。结果多变量logistic回归分析显示,低密度脂蛋白胆固醇(low-density lipoprotein cholesterol, LDL-C)是颈动脉斑块的独立危险因素,而高密度脂蛋白胆固醇(high-density lipoprotein cholesterol, HDL-C)是颈动脉斑块的独立保护因素。以LHR最低五分位数组(Q1)作为参照,颈动脉斑块风险随LHR值的增高而显著增高(Q2:OR 1.448,95% CI 1.082~1.937,P=0.013;Q3:OR 2.414,95% CI 1.754~3.322,P<0.001;Q4:OR 2.939,95% CI 1.945~4.441,P<0.001;Q5:OR 4.884,95% CI 3.143~7.115,P<0.001)。ROC曲线分析显示,LHR预测颈动脉斑块的曲线下面积为0.795(95% CI 0.792~0.807;P<0.001),最佳截断值为3.00(敏感性为68.37%,特异性为75.65%)。LHR≥3.92(Q4和Q5亚组的LHR)是颈动脉不稳定斑块的独立危险因素(OR 2.915,95% CI 2.104~4.040;P<0.001)。LHR预测颈动脉不稳定斑块的曲线下面积为0.658(95% CI 0.633~0.684;P<0.001)。结论LHR是卒中高危人群存在颈动脉斑块的独立预测因素,对颈动脉斑块具有较高的预测价值,其促斑块形成的转化阈值为3.00。当LHR≥3.92时,存在颈动脉不稳定斑块的风险显著增高。

Objective To investigate the relationship between low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (LHR) and asymptomatic carotid plaques and their stability in high-risk stroke population. Methods Between December 2012 and April 2015, a total of 39 944 permanent resident population ≥40 years were used as subjects of the survey from 11 rural communities in Haitou Town, Banzhuang Town and Tashan Town, Ganyu District, and 9 urban communities in Xinpu District and Haizhou District, Lianyungang City using epidemiological survey method of cluster sampling. Excluding those who took lipid-lowering drugs within 3 months and had a history of stroke or transient ischemic attack, 6 592 people at high risk of stroke were finally screened out. Ultrasound was used to detect carotid plaques. The subjects were divided into plaque-free group and plaque group. The latter was further divided into stable plaque group and unstable plaque group. Multivariate logistic regression analysis was used to evaluate the independent risk factor for carotid plaques and their stability. The odds ratio (OR) and 95% confidence interval (CI) were calculated. Receiver Operating Characteristic (ROC) curve was used to evaluate the prediction efficiency of LHR on carotid plaques. Results Multivariate logistic regression analysis showed that low-density lipoprotein cholesterol (LDL-C) was an independent risk factor for carotid plaques, while high-density lipoprotein cholesterol (HDL-C) was an independent protection factor of carotid plaques. Using the lowest quintile (Q1) of LHR as a reference, carotid plaque risk increased significantly with the increasing LHR (Q2: OR 1.448, 95% CI 1.082-1.937, P=0.013;Q3: OR 2.414, 95% CI 1.754-3.322, P<0.001;Q4: OR 2.939, 95% CI 1.945-4.441, P<0.001;Q5: OR 4.884, 95% CI 3.143-7.115, P<0.001). ROC curve analysis showed that the area under the curve (AUC) of LHR predicting carotid plaques was 0.795 (95% CI 0.792-0.807;P<0.001), and the optimal cut-off value was 3.00 (sensitivity 68.37%, specificity 75.65%). LHR ≥3.92 (LHR in the Q4 and Q5 subgroups) was an independent risk factor for unstable carotid plaques (OR 2.915, 95% CI 2.104-4.040;P<0.001). The AUC of the LHR predicting unstable carotid plaques was 0.658 (95% CI 0.633-0.684;P<0.001). Conclusions LHR was an independent predictor of carotid plaques in high-risk stroke patients. It had higher predictive value for carotid plaques, and its conversion threshold for promoting plaque formation was 3.00. When LHR was ≥3.92, there was a significant increase in the risk of unstable carotid plaques.