Correlation between thyroid function and the severity of coronary artery disease

Abstract

Objective To explore the correlation between thyroxine hormone and the severity of coronary artery disease (CAD).Methods 158 patients with coronary adisease were entered consecutively into the study.They were separated into control group (absence of CAD,n=98)and CAD group (presence of CAD,n=60).Based on the number of vessel disease,CAD group was further divided into three sub-groups:single-vessel CAD subgroup (n=30),bi-vessel CAD subgroup (n=15) and multi-vessel CAD subgroup (n=15).Serum free triiodothyronine (fT3),free thyroxine (fT4),thyroid stimulating hormone (TSH) were tested by electrochemiluminescence; high density lipoprotein cholesterol (HDL-C) and total cholesterol (TC) weremeasured by cholesterol oxidase method; and Gensini scoring system was used to evaluate the degree of coronary artery stenosis.Results The levels of fT3 in both bi-vessel CAD and multi-vessel subgroups were higher than those in control group (t=1.947,6.415,both P＜0.05).And the level of fT4 in multi-vessel subgroup was also higher than that in control group (t=3.026,P＜0.05).fT3 was an independent risk factor of CAD using Logistic regression model.In addition,fT3 was negatively correlated with Gensini scoring inmultiple linear regressions.Gensini scores would increase by 1 as long as the level oft fT3 decreases 0.234 pmol/L.Conclusions fT3 level decreased in patients with CAD,and correlated with the severity of CAD.Gensiniscores would increase 1 as long as fT3 decreases 0.234 pmol/L,which could be supposed as a sensitive predictor of CAD. Key words: Thyroid hormones; Coronary artery disease; Gensini scoring