BACKGROUND: In the previous recent reports, subclinical hypothyroidism is an 
independent risk factor for acute myocardial infarction in elderly women. It was 
not established whether a normal range of thyroid stimulating hormone (TSH) 
influences the presence of coronary atherosclerosis. We postulated that the 
level of TSH is risk factor of coronary atherosclerosis in angina patients who 
have normal thyroid function.
METHODS: We studied 344 angina patients (62.5+/-9.72 years, male 50%) who 
underwent elective coronary angiography. TSH, free thyroxine, serum lipid levels 
and high-sensitivity C-reactive protein levels were measured and compared to the 
severity of coronary artery disease.
RESULTS: In patients with high level of TSH (> or =2.1 microIU/mL), age 
(p=0.016), the levels of serum creatinine (p=0.004) and Gensini's score 
(p=0.016) were significantly higher than those in patients with low TSH levels. 
The incidence of multi-vessel disease was higher in patients with high TSH level 
(p=0.026). TSH level showed a significant correlation with age (r=0.109, 
p=0.044) and Gensini's score (r=0.117, p=0.045). The multivariate analysis 
revealed that age (OR 2.39, p=0.001), diabetes (OR 3.74, p=0.001), creatinine 
(OR 2.06, p=0.008), and smoking (OR 1.85, p=0.045) were independent predictors 
for significant coronary artery disease, but TSH level did not predict coronary 
artery stenosis.
CONCLUSIONS: Although the high level of serum TSH is associated with 
multi-vessel disease, it was not the determinant of coronary artery disease in 
patients with normal range of thyroid function.