Published: 2021-05-26

Assessment of prognostic value of FT3, FT4 and TSH among critically ill patients

Richa Giri, Pravin Kumar Yadav, Saurabh Agarwal, Lalit Kumar


Background: Thyroid dysfunction is found to be associated with increased morbidity and mortality rates in intensive care unit (ICU) admitted patients. Critically ill patients who were admitted to ICU showed free triiodothyronine (FT3) levels to be an independent and important predictor of mortality. Decreased levels of free thyroxine (T4) and thyroid stimulating hormone (TSH) showed an indication of worsening of disease and poor prognosis. The most common thyroid hormonal change reported in critically ill patients is reduced serum T3 level. The aim of this study was assessment and prognostic value of thyroid function values among critically ill patients.

Methods: The prospective observational study was conducted at department of medicine, at tertiary care hospital of Kanpur, India on 100 critically ill patients admitted who were more than 18 years of age. Patients with history s/o previous thyroid illness and documented thyroid disease, and clinically evident thyroid enlargement were excluded from the study.

Results: 50 (50.0%) of 100 patients were males and 50 (50.0%) were females. A total 44.0% mortality was reported with 57±11.96 years of mean age of non-survivors. Only FT3 of thyroid functions have shown statistically highly significant differences (p<0.01). 

Conclusions: In our study patient admitted in ICU, FT3 was the strongest predictor of ICU mortality in comparison to all other important parameters included in our study.


Thyroid dysfunction, Critically ill patients, Mortality, Intensive care unit

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