老年维持性血液透析患者高钾血症与不良预后事件相关性的临床研究

Clinical research of the correlation between hyperkalemia and adverse outcome events in elderly patients with maintenance hemodialysis

目的探讨高钾血症及其复发频率对老年维持性血液透析(MHD)患者不良预后的影响。方法采用回顾性队列研究方法收集血液透析治疗的177例老年患者的临床资料。平均年龄(77.28±14.25)岁,其中男109例(61.6%)。依据4个月内的血钾峰值分为<5.0 mmol/L组38例(21.5%)、5.0~5.5 mmol/L组42例(23.7%)及≥5.5 mmol/L组97例(54.8%),记录4个月内高钾血症的频次,将患者分为无高钾组(0次)、低频率组(1~2次)和高频率组(3~4次)。随访1年,终点事件为全因死亡和心血管疾病死亡。采用Kaplan-Meier生存曲线比较各组间累积生存率;采用Cox比例风险回归模型评估高钾血症程度和次数与终点事件的相关性。结果177例患者平均中位随访时间12(1~12)个月,死亡20例(11.3%),其中心血管疾病死亡14例(7.9%)。Kaplan-Meier生存曲线分析显示:血钾5.0~5.5 mmol/L组及≥5.5 mmol/L组的全因死亡率及心血管死亡率均显著性升高(均P<0.05)。多因素Cox回归分析显示:作为连续变量,血钾水平升高是全因死亡和心血管疾病死亡的危险因素(P<0.001);作为分类变量,血钾5.0~5.5 mmol/L组和血钾≥5.5 mmol/L组的全因死亡风险和心血管疾病死亡风险显著高于血钾<5.0 mmol/L组(P<0.05);低频率组和高频率组的全因死亡风险和心血管疾病死亡风险显著高于无高钾组(P<0.05)。结论老年MHD患者血钾>5.0 mmol/L是全因死亡和心血管疾病死亡的独立危险因素,建议将血钾正常范围上限调整至5.0 mmol/L。

Objective To explore the relationship between hyperkalemia and adverse outcomes in elderly maintenance hemodialysis(MHD)patients.Methods A retrospective cohort trial was conducted on 177 MHD patients aged≥60 years in the hemodialysis center of Beijing Shijitan Hospital,Capital Medical University.Baseline data were collected.The mean age was(77.28±14.25)years,among them 109 cases were males(61.6%).According to the peak serum potassium within 4 months,patients were divided into the K+<5.0 mmol/L group(38 cases,21.5%),the 5.0-5.5 mmol/L group(42 cases,23.7%)and the K+≥5.5 mmol/L group(97 cases,54.8%).Based on the frequency of hyperkalemia within 4 months,patients were divided into the 0,1-2 and 3-4 frequency groups.All of patients were followed up for 1 year.The end point events were all-cause mortality and cardiovascular disease(CVD)mortality.Kaplan-Meier survival analysis was used to compare the cumulative survival rate between the 3 groups.A multivariate Cox regression model was employed to analyze the relationship between the degree and frequency of hyperkalemia with all-cause and CVD mortality.Results The mean follow-up time of 177 patients was 12(1-12)months,20(11.3%)patients died of all-cause death and 14(7.9%)of CVD death.Kaplan Meier survival curve showed cardiovascular mortality rate and all-cause mortality were significantly increased in the K+5.0-5.5 mmol/L group and the K+≥5.5 mmol/L group(both P<0.05).Multivariate Cox regression analysis indicated that,as a continuous variable,peak potassium levels were independently associated with an increased risk of all-cause death and CVD death(P<0.001).As a categorical variable,the all-cause mortality risk and CVD mortality risk were significantly higher in both the K+5.0-5.5 mmol/L group and the K+≥5.5 mmol/L group than those in the K+<5.0 mmol/L group(P<0.05),and those were significantly higher in the 1-2 and 3-4 frequency groups than those in the 0 frequency group of hyperkalemia(P<0.05).Conclusion Serum potassium>5.0 mmol/L in elderly MHD patients is an independent risk factor for all-cause and CVD mortality.It is recommended to adjust the upper limit of the normal range of serum potassium to 5.0 mmol/L.