The prognostic value of thyroid function tests in predominantly non-alcoholic cirrhotic patients: a prospective investigation.

Abstract

The prognostic value of thyroid function parameters (T3, T4, rT3 and the rT3:T3 ratio) and common liver tests (serum bilirubin, albumin and prothrombin activity) was investigated on hospital admission in 100 consecutive patients with predominantly non-alcoholic liver cirrhosis. Twenty-nine out of 100 patients had a well compensated cirrhosis and their mean values of thyroid tests were similar to those of 40 healthy controls. A low T3 syndrome was found in the remaining 71 decompensated patients. In these thyroid function parameters were correlated with serum bilirubin and prothrombin activity. Moreover mean values of all thyroid and liver tests, except serum albumin, were significantly different between survivors and nonsurvivors at 3 months. To evaluate the best cut-off value which allowed to predict the outcome of patients, the Receiver Operating Characteristics (ROC) curves were generated for each test by plotting the values obtained in survivors at 3 months (true positives) vs nonsurvivors (false positives). By holding the false positive errors within 10%, the highest percentage of true positive results (i.e. patients dead at 3 months) was observed for the rT3:T3 ratio, rT3 and serum bilirubin at a cut-off point of 0.841, 55 ng/dl and 3.5 mg/dl, respectively. According to the above cut-offs the rT3:T3 ratio had the best positive predictive value (74%; 95% confidence limits 60-90%) in comparison to rT3 and bilirubin.