Overactive Thyroid May Lead to Long-lasting Heart Issues

Hyperthyroidism associated with cardiovascular and blood vessel disease

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) An overactive thyroid gland could put patients at higher risk of hospitalization for heart or blood vessel disease. This could be the case even if the gland was surgically removed.

The thyroid gland is located in the neck and helps regulate the body's metabolism.

In patients with hyper-thyroidism (most commonly caused by the autoimmune disorder, Grave's disease) the metabolism speeds up, potentially leading to fast heart rate, anxiety, weight loss, increased appetite and profuse sweating.

"Speak with your primary care doctor about any history of hyper-thyroidism."

Saara Metso, MD, PhD, principal investigator and assistant chief of endocrinology at Tampere University Hospital in Finland, said that an overactive thyroid can have long-lasting effects on the heart and blood vessels.

Dr. Metso said that this means it is particularly important to monitor heartbeat and blood pressure even years later when patients are no longer experiencing hyperthyroidism.

During the study researchers followed 4,334 patients with overactive thyroid who had the gland surgically removed in Finland between 1986 and 2007, and 12,991 gender-matched patients without a history of hyperthyroidism. Most were women, all were white and the average age was 46. They were followed for just over 10 years.

Investigators reviewed Finland's national Hospital Discharge Registry to determine whether participants were hospitalized during follow up.

Researchers found that patients who received surgery for overactive thyroid were 17 percent more likely to be hospitalized for heart or blood vessel disease compared to those who never experienced hyperthyroidism. The risk was increased for as long as 20 years after surgery.

Other recent studies have raised concern over long-term treatments for overactive thyroid, suggesting that the anti-thyroid medication or radioactive iodine could increase the risk of hospitalization for cardiovascular or blood vessel disease.

However, it was unclear whether the risks were tied to treatments or to the prior overactive thyroid.

"Although overactive thyroid gland is usually easy to diagnose and treat, it may be injurious to the patient's heart and vessels," Dr. Metso said. "It is probably the disease rather than the treatment that affects the patient's heart and vessels permanently."

The research was recently presented at The Endocrine Society's 94th Annual Meeting in Houston, Texas.

Reviewed by: 
Review Date: 
June 27, 2012
Last Updated:
July 7, 2012