People with hyperthyroidism have an increased risk of cardiovascular disease even after successful surgical treatment, researchers reported.
In a population-based cohort study in Finland, hyperthyroid patients had a 50 percent elevation in hospital admission for a range of cardiovascular causes compared with controls, according to Essi Ryodi, MD, of Tampere University Hospital in Tampere, Finland, and colleagues.
And even after thyroidectomy, the difference persisted for several types of cardiovascular disease, Ryodi and colleagues reported online in Clinical Endocrinology.
On the other hand, they found no difference in cardiovascular mortality among patients and controls before or after the surgery.
But this is the first study, Ryodi and colleagues wrote, to demonstrate an increased cardiovascular risk both before and after successful surgical treatment.
For the analysis, Ryodi and colleagues identified all patients who underwent surgery for hyperthyroidism from 1986 through 2007, using the Finish national hospital discharge database.
The database also includes the reasons for all hospital admission of one night or more, allowing evaluation of cardiovascular disease.
Three controls for each patient, matched for age, sex, and county of residence, were randomly selected from the country's population registry.
The cardiovascular causes of hospital admission were broken into eight major groups: hypertension, coronary artery disease, diseases of the pulmonary circulation, arrhythmias, heart failure, cerebrovascular diseases, diseases of arteries and veins, and valvular diseases and cardiomyopathies.