Adding low tri-iodothyronine syndrome (LT3S) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) to a model of established risk factors for heart failure (HF) was found to improve the model’s ability to predict 1-year all-cause mortality in patients with acute decompensated HF, according to study findings published in BMC Endocrine Disorders.
Previous research indicates NT-proBNP can be a useful marker for mortality in patients with established HF. Given that many patients with HF also have LT3S, more research needs to focus on the use of LT3S plus NT-proBNP in predicting mortality risk in patients with acute decompensated HF.
To address this research gap, a group of investigators evaluated the prognostic value of LT3S combined with NT-proBNP in terms of the risk of death in 594 euthyroid patients who were hospitalized with acute decompensated HF at 2 hospitals in China. Routine laboratory measurements provided information on patients’ thyroid function and NT-proBNP.
A total of 27 patients (4.5%) in the study died during hospitalization, and 100 deaths (17.6%) were reported during 1-year follow-up for the 567 patients who were discharged alive.
The cohort was divided into different groups based on reference ranges of free T3 (FT3) levels, including an LT3S group (FT3, <2.3 pg/mL; n=168; age, 61±16 years) and a non-LT3S group (FT3, ≥2.3pg/mL; n=426; age, 57±15 years).
Patients in the LT3S group had a significantly higher 1-year all-cause mortality rate compared with those in the non-LT3S arm (34.6% vs 11.3%, respectively), when adjusted for NT-proBNP (adjusted hazard ratio, 1.85; 95% CI, 1.21-2.82; P =.005). The model of 1-year all-cause mortality included several clinical variables such as systolic blood pressure, body mass index, New York Heart Association (NYHA) functional class, sodium, albumin, and blood urea nitrogen.
Adding LT3S and NT-proBNP to the prediction model with the clinical variables significantly improved the C statistic for 1-year all-cause mortality prediction (C statistic, 0.813; 95% CI, 0.768-0.859; P =.047).
In contrast, there was no association between LT3S and NT-proBNP with an increased risk of in-hospital death (adjusted HR, 1.58; 95% CI, 0.68-3.71; P =.290).
Given the study’s observational nature, the researchers’ were unable to evaluate the possible efficacy of T3 replacement in patients in the LT3S group.
According to the researchers, the findings of the study could “help clinicians more accurately assess the risk of patients with decompensated HF and tailor their therapies.”
Zhao X, Zhang R, Jiang H, et al. Combined use of low T3 syndrome and NT-proBNP as predictors for death in patients with acute decompensated heart failure. BMC Endocr Disord. 2021;21(1):140. doi:10.1186/s12902-021-00801-x