Hyperthyroidism Is Associated with the Development of Vasospastic Angina, but Not with Cardiovascular Outcomes.

Vasospastic angina (VA) is a functional disease caused by the alteration of vasomotor tone. We investigated the association of hyperthyroidism with the development and prognosis of VA. Study data were obtained from a prospective multicenter registry that included patients who had symptoms suggestive of VA. Coronary angiography and an ergonovine provocation test were performed, and patients were classified into a VA and a non-VA group. Among 1239 patients with suspected VA, 831 patients were classified in the VA group. Hyperthyroidism was more common in the VA group than in the non-VA group (10.0% vs. 3.7%, < 0.001). After adjusting for confounding factors, hyperthyroidism was independently associated with a 3.27-fold increased risk of VA. Especially in women, hyperthyroidism was associated with a 4.38-fold higher risk of VA. All-cause death rates did not differ according to the presence or absence of hyperthyroidism. Hyperthyroidism is independently associated with the occurrence of VA especially in women but did not affect the total death in VA patients. Clinicians need to be aware of the role of thyroid function in patients with suspected VA.