ROLE OF THYROID BIOMARKERS IN ASSOCIATION WITH SOFA SCORE IN PREDICTING THE PROGNOSIS OF POST-OPERATIVE CRITICALLY ILL PATIENTS

BACKGROUND Thyroid hormone alterations in critically ill patients are very common and may add to the severity of disease and the outcomes of patients in Intensive Care Unit (ICU). This observational study was conducted to detect the thyroid biomarkers as independent predictors of ICU mortality to predict prognosis more accurately in post-operative critically ill ICU patients with sepsis. This study also tries to determine any association between the thyroid biomarkers and SOFA (sepsis-related organ failure assessment) score. MATERIALS AND METHODS This is a prospective observational study. We investigated free triiodothyronine (FT3), free thyroxine (FT4) and Thyroid Stimulating Hormone (TSH) in low SOFA score patients (LSS; n= 21, SOFA= 0 - 6) and in high SOFA score patients (HSS; n= 82, SOFA > 6). The serum levels of FT3, FT4 and TSH were correlated with SOFA score. Further, prognosis on fifth day of ICU admission was defined on the basis of SOFA score, FT3, FT4 and TSH. RESULTS The serum levels of FT3 (p= 0.004), FT4 (p= 0.025) and TSH (p > 0.05) decreased in HSS than LSS. A negative correlation was observed between thyroid biomarkers and SOFA score (> 6). Patients who deteriorated on the fifth day of ICU admission had significantly high SOFA score (p= 2.15E-06) and significantly low FT3 (p= 3.17E-10), FT4 (p= 4.06E-05) and TSH (p= 2.21E-05) on first day of ICU admission than those who improved on fifth day. CONCLUSION Thyroid biomarkers, specifically low FT3 might be an efficient biomarker or risk factor in evaluating prognosis of the post-operative critically ill patients.