Clinical significance of low triiodothyronine syndrome in critical patients and triiodothyronine impact on evaluation of prognosis / 中华急诊医学杂志

ABSTRACT

Objective To identify the clinical significance of low triiodothyronine syndrome and the potential impact of triiodothyronine (T3) on prognosis in critical patients.Methods A total of 150 critically ill patients enrolled from October 2012 to April 2013 were divided into two groups,namely low thyroidhormone group (n =38,group A) and normal T3 group (n =112,group B).APACHE Ⅱ scores of patients were recorded at admission and thyroid hormone levels were measured on the first and the third day after admission.Then the survival state of 28-day in each group was observed and then the relationship between prognosis and T3 levels was analyzed by receiver operating characteristic (ROC) curve.Results About 25.3％ of 150 critical patients were suffered from low thyroidhormone syndrome and the mortality rate in this group was 42.1％,which was much higher than 29.5％ in normal T3 group.There was no difference in prediction of death rate analyzed by ROC curve between the T3 level and APACHE Ⅱ scores.The area under curve of T3 level was 0.768 (95％ CI:0.701-0.835) and APACHE Ⅱ was 0.783 (95％CI:0.719-0.846).Best cut-off value of T3 level was 0.41 ng/mL resulting in 76.6％ sensitivity and 78.4％ specificity.Conclusions Critically ill patients complicated with low thyroidhormone syndrome has poor prognosis and T3 may be a predictive marker in evaluating the prognosis of critically ill patients.