The serum reverse triiodothyronine (rT₃) values of heart failure patients who died during hospitalization were found significantly higher than the upper limit of the biological reference interval in the clinical work of the author. The prediction of thyroid hormones, especially rT₃, on death during hospitalization of heart failure patients was rare reported in the previous studies, it is of great clinical significance to explore the indicators with predictive value for death during hospitalization in patients with heart failure.

To investigate the relationship between serum thyroid hormones and prognosis during hospitalization in patients with heart failure.

A total of 197 patients with heart failure admitted to Dongzhimen Hospital of Beijing University of Chinese Medicine from April 2019 to April 2022 were included in the study. Baseline data of the study subjects were collected by the electronic medical record system. Fasting venous blood of all subjects was collected within 24 h after admission for total triiodothyronine (TT₃), total thyroxine (TT₄), free triiodothyronine (FT₃), free thyroxine (FT₄), thyroid stimulating hormone (TSH), rT₃ and N-terminal brain natriuretic peptide precursor (NT-pro-BNP). Subjects were divided into death group (n=18) and non-death group (n=179) according to the occurrence of death during hospitalization. Multivariate Logistic regression analysis was used to investigate the influencing factors of death during hospitalization in patients with heart failure. Receiver operating curve (ROC curve) was plotted to evaluate the predictive value of related indicators on death during hospitalization in patients with heart failure, and the area under curve (AUC) of each indicator was calculated and compared by Delong test.

The age and rT₃ of death group were higher than those of non-death group, while FT₃, TT₃ and TSH of death group were lower than those of non-death group, with statistically significant differences (P<0.05). In the non-death group, 66 patients had normal thyroid function, 87 patients had low T₃ syndrome, 15 patients had high FT₄ alone, 3 patients had high TT₄ alone, 5 patients had both high TT₄ and FT₄, 1 patient had low TT₄ alone, 1 patient had high TT₃ alone, and 1 patient had high FT₃ alone. In the death group, 1 patient had normal thyroid function, 14 patients had low T₃ syndrome, and 3 patients had high FT₄ alone. There was significant difference in the incidence of low T₃ syndrome between the two groups (P<0.05). The results of multivariate Logistic regression analysis showed that rT₃ was an influencing factor for death during hospitalization in patients with heart failure〔OR=5.245, 95%CI (2.283, 12.050), P<0.05〕. ROC curve results showed that the AUC of rT₃ was 0.914〔95%CI (0.865, 0.962) 〕, which was higher than that of age (Z=3.137, P=0.002), FT₃ (Z=2.389, P=0.017), TT₃ (Z=2.123, P=0.034) and TSH (Z=3.056, P=0.002) .

Low T₃ syndrome may be a risk factor for death during hospitalization in patients with heart failure. Serum rT₃ is of high predictive value for the prognostic evaluation of patients with heart failure during hospitalization, which need more attention in clinical work.

笔者在临床工作中发现住院期间死亡的心力衰竭患者血清反三碘甲状腺原氨酸（rT₃）检测值多明显高于生物参考区间上限。既往关于甲状腺激素对心力衰竭患者住院期间死亡预测的研究，特别是rT₃预测价值的研究较少。探索对心力衰竭患者住院期间死亡有预测价值的指标具有重要临床指导意义。

探讨血清甲状腺激素与心力衰竭患者住院期间预后的相关性。

纳入2019年4月—2022年4月于北京中医药大学东直门医院住院治疗的197例心力衰竭患者为研究对象。通过电子病历系统收集研究对象的基线资料。所有研究对象入院24 h内采集空腹静脉血检测总三碘甲状腺原氨酸（TT₃）、总甲状腺素（TT₄）、游离三碘甲状腺原氨酸（FT₃）、游离甲状腺素（FT₄）、促甲状腺激素（TSH）、rT₃和N-末端脑钠肽前体（NT-pro-BNP）。根据研究对象住院期间是否死亡分为死亡组（n=18）和非死亡组（n=179）。采用多因素Logistic回归分析探讨心力衰竭患者住院期间死亡的影响因素。绘制受试者工作特征曲线（ROC曲线）评价相关指标对心力衰竭患者住院期间死亡的预测价值，计算ROC曲线下面积（AUC），并采用Delong检验比较各指标的AUC。

死亡组年龄、rT₃高于非死亡组，FT₃、TT₃、TSH低于非死亡组（P<0.05）。非死亡组患者中66例甲状腺功能正常，87例低T₃综合征，15例单独FT₄高，3例单独TT₄高，5例TT₄、FT₄均高，1例单独TT₄低，1例单独TT₃高，1例单独FT₃高；死亡组患者中1例甲状腺功能正常，14例低T₃综合征，3例单独FT₄高。两组患者低T₃综合征发病率比较，差异有统计学意义（P<0.05）。多因素Logistic回归分析结果显示，rT₃是心力衰竭患者住院期间死亡的影响因素〔OR=5.245，95%CI（2.283，12.050），P<0.05〕。ROC曲线结果显示rT₃预测心力衰竭患者住院期间死亡的AUC为0.914〔95%CI（0.865，0.962）〕，大于年龄（Z=3.137，P=0.002）、FT₃（Z=2.389，P=0.017）、TT₃（Z=2.123，P=0.034）、TSH（Z=3.056，P=0.002）。

低T₃综合征可能是心力衰竭患者住院死亡的危险因素，血清rT₃对于心力衰竭患者住院期间的预后判断具有较高价值，临床工作中应予以重视。