169例肝性脑病患者预后的多因素分析

Analysis of prognostic factors of hepatic encephalopathy

目的探讨肝性脑病的预后因素及其意义。方法选取两所三级甲等医院1993年7月至2005年6月肝硬化合并肝性脑病的住院患者169例,采用回顾性队列研究方法,以确诊肝性脑病的日期为随访起点,通过电话、信函或再次入院记录患者的生存情况,以2005年9月30日作为随访终点,患者死亡或接受肝移植及失访的时间也为随访终点。选择32个可能对肝性脑病预后产生影响的临床及理化指标,Cox比例风险模型对患者预后进行生存分析,筛选出独立的预后因素,构建肝性脑病的预后指数(PI)模型。结果169例肝硬化合并肝性脑病患者的中位生存时间是4.4个月,1年生存率为24.32%,2年为18.83%,5年为9.98%。经Cox回归分析,筛选出血钠、BUN、血清总胆固醇、WBC和Child-Pugh分级5个肝性脑病的独立预后因素,得出PI值的计算公式为:PI= 1.218-0.027×血钠+0.039×BUN-0.219×血清总胆固醇+0.046×WBC+1.216×Child-Pugh分级。将本组患者的PI值按大小顺序等分为3组,用Log-Rank检验法比较,3组患者的生存率结果低PI值组>中PI值组>高PI值组。结论血钠、BUN、血清总胆固醇、WBC和Child-Pugh分级是肝性脑病的独立预后因素;PI值与肝性脑病预后呈负相关。

Objective To investigate the prognostic factors of hepatic encephalopathy and their significance. Methods One hundred and sixty-nine patients who developed hepatic encephalopathy and were hospitalized from July 1993 to June 2005 were included in this study. Medical records of these patients were reviewed retrospectively. The follow-up period was from the first episode of hepatic encephalopathy to the death of the patients. For patients whose death could not be confirmed, the follow-up ended on their last interviews, or the date of liver transplantation, or September 30, 2005. Thirty-two variables were selected from clinical and biochemical examinations at the first episode of hepatic encephalopathy. The prognostic factors of hepatic encephalopathy were extracted from the 32 variables by Cox regression analysis and a prognostic index（Pl） model for hepatic encephalopathy was established. Results The median survival time of these 169 patients was 4.4 months, and the cumulative survival rate was 24.32% after 1 year, 18.83% after 2 years and 9.98% after 5 years respectively. Using Cox regression analysis, five factors, serum sodium, blood urea nitrogen （BUN）, total serum cholesterol（Tchol）, white blood cell count（WBC） and the Child-Pugh classification were identified as independent factors that significantly correlated with the outcome of hepatic encephalopathy. The PI value was calculated by the following formula： PI = 1. 218-0. 027 × serum sodium ＋ 0. 039 × BUN - 0. 219 × Tchol ＋ 0. 046 × WBC ＋ 1. 216 × Child-Pugh classification. These ,169 patients were divided equally into low-PI, median-PI and high-PI groups according to their PI values. The order of the cumulative survival rate of three groups was low-PI group〉median-PI group〉high-PI group by Log-Rank test（P〈0.05）. Conclusions Serum sodium, BUN, Tchol, WBC and the Child Pugh classification are independent prognostic factors of hepatic encephalopathy. A high or low P1 indicates a poor or good prognosis of hepatic encephalopathy. PI can serve as a judgment index for the therapeutic approach and prognosis of hepatic encephalopathy.