The Predictive Power of Low T3 Levels among ICU Patients in a Tertiary Care Hospital of Kerala

Abstract

Just a few studies recorded that low thyroid hormones are independent mortality predictors in ICU-admitted patients, indicating the use of thyroid profile in mortality prediction scoring systems. A spectrum of improvements occurs in ICU patients, beginning with low triiodothyronine (T3) accompanied by low thyroxine (T4) and low thyroid-stimulating hormone (TSH) levels. To evaluate whether low T3 levels were responsible for increased mortality among ICU patients in a tertiary care hospital. This is a prospective, observational and interventional study carried on 200 ICU admitted patients aged 30-70 years. The study subjects were categorized into two groups- survivors and non-survivors. Our study results revealed that non-survivors had less T3, less T4, less TSH, more HbA1c indicating that low thyroid levels are playing one of the crucial roles in determining the mortality rate in critically ill patients. Further, we found that the treatment with T4 alone was ineffective while replacement therapy, including T3, proved effective leading to significant clinical improvement. Low T3 syndrome has a significant effect on the mortality rate of critically ill patients. However, a further larger sample of patients should be evaluated to draw more reliable conclusions on Low T3 levels among ICU patients.