FRIDAY, May 3, 2013 (HealthDay News) -- People with a mild form of hyperthyroidism may be at increased risk of death from cardiovascular disease and other causes, according to a new study.
Hyperthyroidism means that the thyroid gland makes and releases too much thyroid hormone, causing symptoms such as weight loss, higher blood pressure and nervousness. A mild form of the condition is called subclinical hyperthyroidism.
In this study, researchers looked at about 6,200 people in Denmark who were diagnosed with subclinical hyperthyroidism between 2000 and 2009 and found that they had a significantly increased risk of dying from cardiovascular disease and other causes.
Of the 706 deaths among people with subclinical hyperthyroidism, 15 percent could be attributed to the thyroid condition, according to the study, which is scheduled for presentation at the European Congress of Endocrinology, held April 27 to May 1 in Copenhagen.
Increased risk was also seen in people with high-normal levels of thyroid activity. Of the nearly 13,500 patients in this range, more than 1,000 died of various causes. Of those deaths, 17 percent were associated with the thyroid condition.
It's difficult to put exact numbers on the actual number of excess deaths caused by subclinical hyperthyroidism or high-normal levels of thyroid activity, or to know if treating these conditions would reduce the risk of death, said study author Christian Selmer, of Gentofte University Hospital in Denmark, and colleagues.
"I think the take-home message is that if a person has a family history with any thyroid problem, or has any signs of thyroid problems, then they should go for a checkup," Selmer said in a news release from the European Society of Endocrinology. "More than that, their family doctors need to be aware that any sign of thyroid abnormality can affect cardiovascular health, and they should act accordingly."
Although the study tied subclinical hyperthyroidism to a higher risk of death, it did not prove a cause-and-effect relationship. Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
The American Academy of Family Physicians has more about hyperthyroidism.