Hypothyroidism in coronary heart disease and its relation to selected risk factors

Otto Mayer Jr¹, Jaroslav Šimon¹, Jan Filipovský¹, Markéta Plášková², Richard Pikner¹

¹Center of Preventive Cardiology, 2nd Department of Internal Medicine, Charles University, Medical Faculty, Plze , Czech Republic; ²Department of Preventive Cardiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic

Introduction: Hypothyroidism (HT) has been found a predictor of cardiovascular diseases. We aimed to ascertain the prevalence of HT in patients with manifest coronary heart disease (CHD), and to establish its association with conventional risk factors.

Methods: 410 patients, 6–24 months after hospitalization for acute coronary syndrome, and/or revascularization, were included into the cross-sectional study.

Results: The prevalence of thyroid dysfunction was found in males and females as follows: overt HT, ie, thyroid stimulating hormone (TSH) > 3.65 mIU/L and free thyroxine (fT4) < 9 pmol/L and/or L-thyroxine substitution, in 2.6% and 8.4%, respectively; subclinical HT (TSH >3.65, fT4 9–23 and no substitution) in 4.3% and 15.0%, respectively. Higher prevalence of HT was found in females with hypercholesterolemia, and in males and females with concomitant positive thyroid peroxydase antibodies. Hypothyroid subjects had higher total homocysteine in both genders and von Willebrand factor in males only. Hypothyroid females had higher total  and LDL cholesterol, and were more often treated for diabetes.

Conclusions: HT was found highly prevalent in patient with clinical coronary heart disease, mainly in females, and was associated with several cardiovascular risk factors.

Keywords: hypothyroidism, coronary heart disease, cholesterol, homocysteine, diabetes