脓毒症进展为慢性危重症患者死亡风险的列线图构建与验证

Construction and validation of a Nomogram for predicting mortality risk in patients with sepsis progressing to chronic critical illness

目的探讨影响脓毒症进展为慢性危重症(CCI)患者预后的危险因素,构建并验证其院内死亡风险的列线图模型。方法从美国重症监护医学信息数据库-Ⅳ(MIMIC-Ⅳ)筛选出符合脓毒症进展为CCI标准的患者为研究对象,采用回顾性研究收集患者临床资料,最终纳入928例患者,按照7∶3比例随机分为建模组(n=649)和验证组(n=279);以院内死亡为结局,将患者分为存活组和死亡组。根据结局对建模组进行单因素、多因素Logistic回归分析;根据独立危险因素构建预测脓毒症进展为CCI患者院内死亡的列线图模型;采用一致性指数及校准曲线评价列线图模型的区分度和校准度,再通过验证组进行验证。结果在纳入的928例脓毒症进展为CCI患者中,存活组723例,死亡组205例,院内病死率为22.1%。年龄(OR=1.021,95%CI:1.007~1.036,P=0.004)、体质量(OR=0.988,95%CI:0.979~0.997,P=0.016)、急性生理学Ⅲ(APSⅢ)评分(OR=1.013,95%CI:1.004~1.023,P=0.004)、血碱性磷酸酶(OR=1.002,95%CI:1.000~1.003,P=0.023)、持续床边血液滤过(CRRT)时间(OR=1.065,95%CI:1.023~1.108,P=0.002)、机械通气时间(OR=1.117,95%CI:1.056~1.184,P<0.001)为脓毒症进展为CCI患者院内死亡的独立影响因素。根据危险因素构建预测模型,进行一致性指数分析,结果显示建模组一致性指数为0.75(95%CI:0.70~0.80),验证组一致性指数为0.74(95%CI:0.68~0.81),建模组与验证组校准曲线均接近标准曲线。结论基于年龄、体质量、血碱性磷酸酶、APSⅢ评分、CRRT和机械通气时间6项指标构建的列线图模型对脓毒症进展为CCI的死亡风险具有良好的区分度及校准度,有助于临床医师评估患者预后。

Objective To explore the risk factors affecting the prognosis of sepsis patients progressing to chronic critical illness(CCI),and to construct and validate a Nomogram model for predicting in-hospital mortality risk.Methods Patients who met the criteria for sepsis progressing to CCI were selected from the Medical Information Mart for Intensive CareⅣ(MIMIC-Ⅳ)database in the United States as the research objects.Clinical materials of patients were collected retrospectively,and a total of 928 patients were included.The patients were randomly divided into modeling group(n=649)and validation group(n=279)at a ratio of 7 to 3;the patients were also divided into survival group and mortality group based on in-hospital mortality.Univariate and multivariate Logistic regression analyses were performed on the modeling group based on the outcomes;a Nomogram model for predicting in-hospital mortality in sepsis patients progressing to CCI was constructed based on independent risk factors;the discrimination and calibration of the Nomogram model were evaluated by the concordance index and calibration curve,and then validated by the validation group.Results Among the 928 sepsis patients progressing to CCI,723 cases were in survival group and 205 cases in mortality group,with an in-hospital mortality rate of 22.1%.Age(OR=1.021,95%CI,1.007 to 1.036,P=0.004),body mass(OR=0.988,95%CI,0.979 to 0.997,P=0.016),the Acute Physiological ScoreⅢ(APSⅢ)score(OR=1.013,95%CI,1.004 to 1.023,P=0.004),blood alkaline phosphatase(OR=1.002,95%CI,1.000 to 1.003,P=0.023),continuous renal replacement therapy(CRRT)duration(OR=1.065,95%CI,1.023 to 1.108,P=0.002),and mechanical ventilation duration(OR=1.117,95%CI,1.056 to 1.184,P<0.001)were identified as independent influencing factors for in-hospital mortality in sepsis patients progressing to CCI.A prediction model was constructed based on these risk factors,and the concordance index analysis showed that the concordance index was 0.75(95%CI,0.70 to 0.80)in the modeling group and 0.74(95%CI,0.68 to 0.81)in the validation group.The calibration curves of both themodeling group and the validation group were close to the standard curve.Conclusion Nomogram model constructed based on the 6 indicators including age,body mass,blood alkaline phosphatase,APSⅢscore,CRRT,and mechanical ventilation duration has good discrimination and calibration for predicting the mortality risk of sepsis patients progressing to CCI,which is helpful for clinicians to assess patient′s prognosis.