红细胞分布宽度与陈旧性心肌梗死并维持性血液透析患者心力衰竭程度及短期不良预后的关系

Association of red cell distribution width with severity of heart failure and its predictive value for short-term poor prognosis in patients with old myocardial infarction undergoing maintenance hemodialysis

目的探讨红细胞分布宽度(RDW)与陈旧性心肌梗死并维持性血透析患者心力衰竭程度是否相关及其对患者短期不良预后的预测价值。方法共纳入2012-2016年于贵州省人民医院心内科因心力衰竭住院且既往明确诊断为心肌梗死并于本院肾内科长期行维持性血液透析的患者共计107例,记录患者的基线临床资料,随访6个月,按患者预后分为生存组及死亡组;按NYHA心功能分级分为Ⅱ～Ⅳ级;按心力衰竭类型分为射血分数降低的心力衰竭(HFrEF,EF<40%)、射血分数保留的心力衰竭(HFpEF,EF≥50%)和射血分数临界的心力衰竭(HFmrEF,EF 40%～49%)。分析RDW与患者心力衰竭程度相关性及其对患者短期不良预后的预测价值。结果 (1) NYHAⅡ级、Ⅲ级和Ⅳ级患者的RDW分别为(37.1±1.1) f L、(39.5±2.6) f L和(46.3±5.3) f L,三组间RDW水平比较差异有显著统计学意义(F=45.13,P<0.01),两两比较差异均有统计学意义(P<0.05);NYHAⅡ级、Ⅲ级和Ⅳ级患者的N末端脑钠肽前体(NT-BNP)水平分别为(900.1±383.3) pg/mL、(3 570.9±2974.4) pg/mL和(7 788.3±4 583.6) pg/mL,三组间NT-BNP水平比较差异有显著统计学意义(F=28.77,P<0.01),两两比较差异也均有统计学意义(P<0.05);多元线性回归分析显示RDW与NT-BNP存在线性正相关(R2=0.339)。(2) HFrEF组、HFpEF组和HFmrEF组患者中,RDW分别为(43.1±5.6) dL、(38.2±0.7) dL及(41.6±5.8) fL,与HFpEF组比较,HFrEF组及HFmrEF组患者的RDW水平明显升高,差异具有统计学意义(P<0.05),HFrEF组较HFmrEF组RDW也有所升高,但差异无统计学意义(P>0.05)。(3) RDW预测患者短期不良预后的ROC曲线下面积为0.95,其预测价值高于NT-BNP。最佳截点值为46.5 fL。结论 RDW可反映陈旧性心肌梗死并维持性血液透析的心力衰竭程度,其水平与心衰程度呈正相关;RDW可用于预测该类患者短期不良预后,其价值优于NT-BNP;HFrEF及HFmrEF组患者的RDW水平明显升高。

Objective To study the association of red cell distribution width（RDW） with severity of heart failure and the predictive value of RDW for short-term poor prognosis in patients with old myocardial infarction undergoing maintenance hemodialysis. Methods A total of 107 hospitalized patients due to heart failure who were diagnosed as myocardial infarction in Department of Cardiology, Guizhou Provincial People＇s Hospital and underwent maintenance hemodialysis in Department of Nephrology, Guizhou Provincial People＇s Hospital from 2012 to 2016 were recruited.Baseline clinical data of patients were recorded. The patients were followed up for 6 months, which were divided into survival group and death group according to the prognosis of the patients. According to the NYHA heart function classification, the patients was divided into Ⅱ-Ⅳ level. According to the type of heart failure, they were divided into heart failure with reduced ejection fraction（HFrEF, EF40%）, heart failure with preserved ejection fraction（HFpEF, EF≥50%）and heart failure with critical ejection fraction（HFmrEF, EF 40%-49%）. Correlation between RDW and the degree of heart failure and its value in predicting the short-term adverse prognosis of patients were analyzed. Results（1） The levels of RDW in patients with NYHA Ⅱ, NYHA Ⅲ, NYHA Ⅳ were（37.1±1.1） fL,（39.5±2.6） fL,（46.3±5.3） fL, respectively. The difference in RDW level among the three groups were statistically significant（F=45.13, P〈0.01）, and the difference between each two groups were also statistically significant（P〈0.05）. The levels of NT-BNP in patients with NYHA Ⅱ, NYHA Ⅲ, NYHA Ⅳ were（900.1±383.3） pg/mL,（3 570.9±2 974.4） pg/mL,（7 788.3±4 583.6） pg/mL, respectively. The difference in NT-BNP level among the three groups were statistically significant（F=28.77,P〈0.01）, and the differences between each two groups were also statistically significant（P〈0.05）. The liner regression analysis showed that RDW was positively correlated with NT-BNP（R2=0.339）.（2） The levels of RDW in patients in HFrEF group, HFpEF group and HFmrEF group were respectively（43.1±5.6） fL,（38.2±0.7） fL and（41.6±5.8） fL. The levels of RDW in HFrEF group and HFmrEF group was significantly higher than that in HFpEF group（P〈0.05）, and the level of RDW in HFrEF group was similar with that in HFmrEF group（P〈0.05）.（3） The area under the ROC curve（AUCs） for RDW was 0.95, whose predictive value was higher than NT-BNP. The best cutoff was 46.5 fL. Conclusion RDW were positively associated with the degree of heart failure in patients with old myocardial infarction undergoing maintenance hemodialysis. RDW can be used to predict short-term poor prognosis of the patients, and its value is superior to NT-BNP.The level of RDW in HFrEF and HFmrEF group is significantly increased.