Non-thyroidal illness syndrome and its relationship with mortality risk in critically ill children

Laura Carreras; Isolina Riaño; Ana Vivanco; Noelia Avello; Tania Iglesias; Corsino Rey

doi:10.3389/fped.2023.1142332

Non-thyroidal illness syndrome and its relationship with mortality risk in critically ill children

Front Pediatr. 2023 Mar 3:11:1142332. doi: 10.3389/fped.2023.1142332. eCollection 2023.

Authors

Laura Carreras¹, Isolina Riaño^{1

2

3

4}, Ana Vivanco¹, Noelia Avello⁵, Tania Iglesias⁶, Corsino Rey^{1

2

3

4}

Affiliations

¹ Department of Pediatrics, Hospital Universitario Central de Asturias, Oviedo, Spain.
² Department of Pediatrics, University of Oviedo, Oviedo, Spain.
³ Health Research Institute of the Principality of Asturias (ISPA), Oviedo, Spain.
⁴ Spain Primary Care Interventions to Prevent Maternal and Child Chronic Diseases of Perinatal and Developmental Origin (RICORS), Institute of Health Carlos III, Madrid, Spain.
⁵ Clinical Biochemistry, Laboratory of Medicine, Hospital Universitario Central de Asturias, Oviedo, Spain.
⁶ Statistical Consulting Unit of the Scientific-Technical Services of the University of Oviedo, Gijón, Spain.

Abstract

Introduction: Non-thyroidal illness syndrome (NTIS) is considered to be associated with adverse outcomes in critically ill children.The hypothesis that thyroid hormones and inflammatory markers are associated with increased prediction of mortality risk scores is tested in this paper.

Methods: A prospective observational study was set up in a pediatric intensive care unit (PICU). One hundred and three patients were included. NTIS was defined as a low free triiodothyronine (FT3) value for the patient's age. Thyroid hormones levels and inflammatory markers were determined at admission: FT3, FT4 (free thyroxine), TSH (thyroid-stimulating hormone), rT3 (reverse triiodothyronine), CRP (C-reactive protein) and PCT (Procalcitonin). They were compared between children with a pediatric risk of mortality score PRISM-III >75th percentile (group A, n= 25) and the rest (group B, n = 78).

Results: A FT4 value lower than 16.6 pmol/L showed an area under the curve (AUC) of 0.655 (0.56-0.78, p = 0.02), with 76% sensitivity and 61.5% specificity to detect a high risk of mortality. A multiple regression analysis revealed that a FT4 lower than 16.6 pmol/L [OR: 4.92 (1.60-18.19), p = 0.009] and having NTIS [OR: 6.04 (1.45-27.93), p = 0.016] could predict a high risk of mortality.

Conclusions: In unselected critically ill children, FT4 and FT3 values at admission could be used as a good predictor of a high mortality risk. We have not achieved a predictive model that combines hormones with inflammatory markers.

Keywords: critically – ill patients; inflammatory markers; mortality scores; non-thyroidal illness syndrome (NTIS); thyroid hormone.

Grants and funding

This study was carried out thanks to partial funding from an Ernesto Sánchez Villares Foundation grant. TSH, FT3 and FT4 reagents were donated by Roche Diagnostics.