Objective The prognosis of patients with acute myocardial infarction (AMI) is related to age,comorbidities,and other factors,in which non-thyroid sick syndrome (NTIS) may also be an important factor.In this study,determination of blood free triiodothyronine (FT3) was used to explore the short-term and long-term mortality relationship of NTIS with acute myocardial infarction.Methods A total of 1 019 cases of newly diagnosed patients with acute myocardial infarction were enrolled.According to FT3 levels,the enlisted subjects were divided into Quartile 1-4 groups; survival group and non-survival group; normal thyroid function and NTIS group.The enrolled subjects were followed-up for 6-90 months,with the median follow-up time of 44.5 months.Using logistic regression and Cox hazards model,the relationships of short-term and long-term mortality in AMI with NTIS or FT3 were compared.Results The incidence of NTIS in patients with AMI was 27.78％.With the progressively decreasing FT3 and FT3/FT4 ratio,the mortality rates were progressively increased (Quartile 1 group 9.4％,Quartile 2 group 13.8％,Quartile 3 group 14.3％,Quartile 4 group 34.0％,P＜0.01).After being adjusted,FT3 was the strongest influencing factor of mortality within 30 days (RR =0.212,95％ CI 0.125-0.359).Multivariate Cox regression analysis showed that FT3 was independently associated with long-term mortality (RR =0.674,95％ CI 0.514-0.885).Kaplan-Meier showed significant difference in mortality between quartile 1-3 groups and the Quartile 4 group.Even FT3 level was within the low normal range,it was related with the mortality in AMI.Conclusions NTIS is common in patients with AMI.After being adjusted,FT3 was the strongest predictor of mortality within 30 days,and low FT3level in AMI patients was an independent risk factor for long-term all-cause mortality.Even FT3 level was within the normal range,it was still related with mortality in myocardial infarction.

Objective To determine the prognostic significance of non-thyroidal illness syndrome(NTIS) and FT3 on long-term all-cause and cardiovascular mortality in patients with coronary artery disease(CAD).Methods A total of 1 354 patients underwent coronary angiograhy and participated in the study.After screening,984 patients with CAD were enrolled finally and divided into NTIS group and euthyroid group.The admitted patients were also classified into Tertile 1-3 groups based on FT3 value.The relationship of long-term all-cause and cardiovascular mortality with FT3 was investigated by multivariate Cox regression analysis.Results 129 out of 984 patients had NTIS.As FT3 value decreased,both long-term all-cause mortality (Tertile 1 group 9.6％,Tertile 2 group 11.5％,Tertile 3 group 20.9％,P＜0.01) and cardiovascular mortality (Tertile 1 group 4.5 ％,Tertile 2 group 7.2％,Tertile 3 group 11.0％,P＜0.01) gradually increased.After adjusting for all factors,FT3 (HR =0.614,95％ CI 0.439-0.859)was independently associated with long-term all-cause mortality.FT3 (HR =0.605,95％ CI 0.370-0.986)was also a risk factor for cardiovascular mortality.Conclusion NTIS exists in patients with CAD without myocardial infarction.FT3 reduction is an independent risk factor for long-term all-cause and cardiovascular mortality in patients with CAD.