Negative association between free triiodothyronine level and international normalized ratio in euthyroid subjects with acute myocardial infarction

• Published in: Acta pharmacologica Sinica Vol. 32; no. 11; pp. 1351 - 1356
• Main Authors: Li, Li, Guo, Chang-yan, Yang, Jing, Jia, En-zhi, Zhu, Tie-bing, Wang, Lian-sheng, Cao, Ke-jiang, Ma, Wen-zhu, Yang, Zhi-jian
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.11.2011; Nature Publishing Group
• Subjects: Acute Disease; Adult; Aged; Aged, 80 and over; Biomedical and Life Sciences; Biomedicine; China - epidemiology; Euthyroid Sick Syndromes - blood; Euthyroid Sick Syndromes - complications; Euthyroid Sick Syndromes - epidemiology; Female; FT3; Humans; Immunology; Internal Medicine; International Normalized Ratio; Male; Medical Microbiology; Middle Aged; Myocardial Infarction - blood; Myocardial Infarction - complications; Myocardial Infarction - epidemiology; Original; original-article; Pharmacology/Toxicology; Prothrombin Time; Thyroid Function Tests; Thyroxine - blood; Triiodothyronine - blood; Vaccine; 国际标准化; 急性心肌梗死; 比值; 活化部分凝血活酶时间; 游离; 甲状腺功能; 负相关; China; free triiodothyronine; prothrombin time; international normalized ratio; acute ST elevation myocardial infarction; Chinese euthyroid subject; free thyroxine
• ISSN: 1671-4083; 1745-7254; 1745-7254
• DOI: 10.1038/aps.2011.118

Aim： To investigate the relationship between free triiodothyronine （FT3） and the international normalized ratio （the ratio of the prothrombin time of a patient to the normal sample, INR） in Chinese euthyroid subjects with acute ST-segment elevation myocardial infarction （STEMI）. Methods： A total of 235 consecutive patients （177 males, 54 females） with STEMI were enrolled. Anthropometric and laboratory mea- surements, including heart rate, respiratory rate, blood pressure, body temperature, platelet count, INR, prothrombin time, activated partial thromboplastin time, FT3, free thyroxine （FT4）, and thyroid-stimulating hormone, were collected from all the patients. The levels of FT3 and FT4 were measured with a full-automatic immune analyzer. The INR was determined using a coagulation analyzer. Results： Patients were classified into 4 groups according to their quartile FT3 and FT4 levels： 0.40-3.09 （n=52）, 3.$0-3.69 （n=56）, 3.70-439 （n=64） and 4.30-7.10 （n=59） for FT3; 4.9-14.8 （n=57）, $4.9-16.8 （n=58）, 16.9-18.7 （n=57） and 18.8-29.0 （n=59） for FT4. Subjects with a high FT3 level had significantly lower values of INR than those with a low FT3 level （P=0.01）. Multiple linear regression analysis revealed decreased serum FT3 as an independent risk factor for elevated INR values （β=-0.139, P=0.025）. The value of INR was similar among the 4 groups according to the quartile FT4 levels （P=0.36）. Conclusion： Free triiodothyronine was negatively associated with INR in the patients with acute STEMI and normal thyroid function.