肝衰竭患者能量代谢与血清甲状腺激素水平的相关性及其对预后的影响

Association of energy metabolism with serum thyroid hormone levels in patients with liver failure and their impact on prognosis

目的探讨肝衰竭患者终末期肝病模型(MELD)评分、能量代谢与血清甲状腺激素水平的相关性以及对病情及预后的预测价值。方法选取2016年11月—2019年4月在首都医科大学附属北京佑安医院肝病中心四科住院的60例肝衰竭患者并随访分为死亡组(23例)和存活组(37例),检测能量代谢及甲状腺功能等指标进行比较分析。两组连续变量的比较,符合正态分布的采用独立样本t检验,非正态分布的采用Mann-Whitney U检验;分类变量两组间比较采用χ^(2)检验。采用Spearman相关系数评价各指标的相关性。受试者工作特征(ROC)曲线分析血清总三碘甲状腺原氨酸(TT3)、游离三碘甲状腺原氨酸(FT3)水平预测肝衰竭患者预后的最佳分界点。结果所有肝衰竭患者低TT3和低FT3的发生率为分别为78.2%和69.1%,死亡组和存活组的低TT3发生率分别为95.2%和67.6%,低FT3的发生率分别为90.5%和55.9%,差异均具有统计学意义(P值均<0.05)。死亡组的MELD评分显著高于存活组[26.0(21.0~29.0)vs 21.0(19.0~24.0),Z=-3.369,P=0.001],而血清TT3、FT3水平显著低于存活组[0.69(0.62~0.73)vs 0.83(0.69~0.94)、2.17(1.99~2.31)vs 2.54(2.12~2.86),Z值分别为-2.884、-2.876,P值均<0.01]。MELD评分与血清TT3、FT3、促甲状腺激素(TSH)水平及呼吸商(RQ)呈负相关(r值分别为-0.487、-0.329、-0.422、-0.350,P值均<0.01),RQ与血清TT3、FT3水平呈正相关(r值分别为0.271、0.265,P值均<0.05)。通过血清TT3、FT3水平预测肝衰竭患者生存预后的最佳分界点分别为0.75 nmol/L、2.37 pmol/L,其敏感度分别为67.6%、64.7%,特异度分别为90.5%、81.0%。结论肝衰竭患者可出现异常能量代谢状态导致呼吸商降低,并可出现甲状腺激素水平的异常,对评估肝衰竭患者病情严重程度及预后具有潜在的临床应用价值。

Objective To explore the predictive value of the model for end-stage liver disease(MELD)score,energy metabolism and serum thyroid hormone levels on the severity and prognosis of patients with liver failure and their correlation.MethodsThis study collected clinicopathological data from 60 liver failure patients,e.g.,end-stage liver disease(MELD)score,energy metabolism,and serum thyroid hormone levels.The χ^(2) test was performed to analyze the categorical variables,while the Mann-Whitney U test and independent sample t test were performed to assess the continuous variables between the two groups.Spearman correlation coefficient test was used to evaluate correlation of each index.The receiver operating characteristic(ROC)curve was used to analyze the optimal cut-off points of serum total triiodothyronine(TT3)and free triiodothyronine(FT3)levels in predicting prognosis of the patients.Results The rates of low TT3 and FT3 levels in liver failure patients were 78.2%and 69.1%,respectively,whereas the low TT3 rates were 95.2%and 67.6%and the low FT3 rates were 90.5%and 55.9%in survival and non-survival groups of patients,respectively(both P<0.05).Moreover,the MELD score was significantly higher in the non-survival patients than in survival patients[26.0(21.0-29.0)vs 21.0(19.0-24.0),Z=-3.396,P=0.001],while TT3 and FT3 levels were significantly lower in the non-survival patients than in the survival patients[0.69(0.62-0.73)vs 0.83(0.69-0.94)and 2.17(1.99-2.31)vs 2.54(2.12-2.86),respectively;Z=-2.884、-2.876,all P<0.01].The MELD score was negatively associated with serum TT3,FT3,and thyroid stimulating hormone(TSH)levels and the respiratory quotient(RQ)(r=-0.487、-0.329、-0.422、-0.350,all P<0.01),whereas the RQ was associated with serum TT3 and FT3 levels(r=0.271、0.265,all P<0.05).The optimal cutoff values in predicting the severity and survival of patients was 0.75 nmol/L and 2.37pmol/L with the sensitivity values of 67.6%and 64.7%and the specificity of 90.5%and 81.0%,respectively.Conclusion Abnormal thyroid hormone levels and low respiratory quotient could be used to predict the severity and prognosis of patients with liver failure.