强离子间隙对急性肾损伤危重患者预后的预测价值

Predictive value of strong ion gap in the prognosis of critically ill patients with acute kidney injury

目的探讨强离子间隙(SIG)对急性肾损伤(AKI)危重患者短期及长期预后的预测价值。方法通过美国重症监护医学信息数据库(MIMIC-IV)(V 2.0)获取2008年至2019年ICU中成年AKI患者9118例的数据。根据AKI危重患者90 d预后情况分为存活组和死亡组。采用限制性立方样条(RCS)分析SIG水平与90 d全因死亡风险的关系,确定SIG的最佳截断值,并将患者分为低SIG组和高SIG组。采用Kaplan-Meier法比较低SIG组和高SIG组30和90 d累积生存率。采用多因素Cox回归模型分析SIG与AKI患者30、90 d全因死亡率的关系。亚组分析进一步研究SIG水平与90 d全因死亡率可能的交互作用。结果根据AKI危重患者90 d预后情况分为存活组6058例和死亡组3060例,90 d全因死亡率为33.56%。两组患者性别、年龄、序贯器官衰竭评估评分、查尔森合并指数、阴离子间隙、白蛋白、血磷、SIG、WBC、Hb、红细胞分布宽度、PLT、肌酐、尿素氮、PT、PaO2、血总钙、血镁、去甲肾上腺素、机械通气、连续性肾脏替代治疗、合并高血压、房颤、肝硬化、急性胰腺炎、心肌梗死、心脏骤停、脓毒症比例、总住院时间比较,差异均有统计学意义(均P<0.05)。RCS分析显示,AKI危重患者SIG水平与90 d全因死亡风险呈非线性趋势关系(P=0.010)。以SIG=4.87 mmol/L为截断值,将患者分为低SIG组(<4.87 mmol/L)4592例和高SIG组(≥4.87 mmol/L)4526例。低SIG组30和90 d全因死亡率分别为19.60%和26.26%,高SIG组分别为33.65%和40.96%,两组比较差异均有统计学意义(均P<0.01)。Kaplan-Meier生存曲线显示,与低SIG组比较,高SIG组患者30和90 d累积生存率均较低,差异均有统计学意义(均P<0.01)。多因素Cox回归分析表明,高SIG水平(≥4.87 mmol/L)是AKI危重患者30和90 d全因死亡率的独立危险因素(均P<0.01)。亚组分析显示,除了年龄、合并高血压外,大多数亚组分层因素对SIG水平与90 d全因死亡率之间的关系没有显著影响。结论高SIG水平(≥4.87 mmol/L)是AKI危重患者全因死亡率的独立危险因素,SIG对AKI危重患者的预后有一定的预测价值,有助于临床医生早期识别预后不良人群。

Objective To explore the predictive value of strong ion gap(SIG)in the short-term and long-term prognosis of critically ill patients with acute kidney injury(AKI).Methods The clinical data of adult patients with AKI in the intensive care unit were obtained from the United States Intensive Care Database(MIMIC-IV,version v2.0;2008-2019).According to the 90 d prognosis,the patients were divided into survival group and death group.Restricted cubic spline(RCS)was used to analyze the relationship between SIG and 90 d all-cause mortality to determine the optimal cut-off value of SIG,according to the value of SIG,the patients were divided into low SIG group and high SIG group.The Kaplan-Meier method was used to compare the 30 and 90 d cumulative survival rates of the low SIG group and the high SIG group;multivariate Cox regression model was used to analyze the association of SIG with 30 and 90 d all-cause mortality.Su bgroup analysis to further investigate the possible interaction between SIG levels and 90 d all-cause mortality.Results A total of 9118 critically ill patients with AKI were included,including 6058 cases in survival group and 3060 cases in death group according to the 90 d prognosis.The 90 d all-cause mortality was 33.56%.There were significant differences in age,sex,sequential organ failure score,charlson combined index,anion gap,albumin,blood phosphate,SIG,WBC,Hb,red blood cell distribution width,PLT,creatinine,blood urea nitrogen,PT,PaO2,total blood calcium,blood magnesium,norepinephrine,mechanical ventilation,continuous renal replacement therapy,hypertension,atrial fibrillation,liver cirrhosis,acute pancreatitis,myocardial infarction,cardiac arrest,sepsis,and hospitalization time between the survival and death groups(all P<0.05).RCS showed that there was a non-linear relationship between SIG and the risk of 90 d all-cause mortality in patients with AKI(P=0.010).According to the optimal SIG cut-off value(4.87 mmol/L),the patients were divided into low SIG group(<4.87 mmol/L,n=4592)and high SIG group(≥4.87 mmol/L,n=4526).The 30 and 90 d all-cause mortality in the low SIG group were 19.60%and 26.26%,and in the high SIG group were 33.65%and 40.96%,respectively(both P<0.01).Kaplan-Meier survival curve showed that compared with the low SIG group,the high SIG group had lower 30 and 90 d cumulative survival rates(both P<0.01).Multivariate Cox regression analysis showed that elevated SIG was an independent risk factor for 30 and 90 d all-cause mortality in critically ill patients with AKI(both P<0.01).Subgroup analysis showed that,except for age and hypertension,most subgroup stratification factors had no significant impact on the relationship between SIG levels and 90 d all-cause mortality.Conclusion Elevated SIG(≥4.87 mmol/L)is an independent risk factor for all-cause mortality in critically ill patients with AKI.SIG has a certain predictive value for the prognosis of critically ill patients with AKI,and helps clinicians to identify the population with poor prognosis early.