DALLAS, Oct. 31, 2017 -- High and high-normal levels of a thyroid hormone called FT4, were associated with artery disease and death in elderly and middle-aged people, according to new research in Circulation Research, an American Heart Association journal.
Researchers analyzed data from 9,420 participants (average age 65, 57 percent women) in the Rotterdam Study looking at data on two types of hormones: thyroid-stimulating hormone and free thyroxine (known as FT4) and their link to atherosclerosis and death due to coronary heart disease, cerebrovascular disease or other artery-related illness.
FT4 is a hormone produced by the thyroid gland that helps control the rate at which the body uses energy. Atherosclerosis is the process of progressive thickening and hardening of the walls of arteries from fat deposits on their inner lining. Researchers determined asymptomatic atherosclerosis by measuring coronary artery calcification.
After a median follow-up of 8.8 years, researchers noted 612 atherosclerosis-related cardiovascular deaths and 934 first-time atherosclerosis-related cardiovascular events. Increasing FT4 levels were associated with:
- twice the odds of having high levels of coronary artery calcification scores - which may be an indicator of subclinical atherosclerosis;
- 87 percent greater risk of suffering an atherosclerosis-related cardiovascular event; and
- double the risk of atherosclerosis-related cardiovascular death.
"We expected that thyroid function would influence the risk of developing atherosclerosis by affecting cardiovascular risk factors such as blood pressure. However, our results remained very similar after accounting for several cardiovascular risk factors," said lead study author Arjola Bano, M.D., M.Sc., D.Sc., a researcher in internal medicine and epidemiology at Erasmus University in Rotterdam, the Netherlands. "This suggests that mechanisms other than traditional cardiovascular risk factors may play a role.
"Our findings suggest that thyroid hormone FT4 measurement can help identify individuals at increased risk of atherosclerosis."
The study is believed to be the first population-based study investigating the relationship of thyroid function with atherosclerosis from subclinical atherosclerosis to overt disease and death.
Authors note that the study did not measure thyroid hormone levels over time and included mostly white middle-age adults so the results may not be generalized to other populations.
"Future studies should clarify the exact mechanisms that can explain the link between thyroid function and atherosclerosis. This could help to identify potential targets for future preventative strategies," Bano said.
###
Co-authors are Layal Chaker, M.D., M.Sc.; Francesco Mattace-Raso, M.D., Ph.D.; Aad van der Lugt, M.D., Ph.D.; Arfan Ikram, M.D., Ph.D.; Oscar Franco, M.D., Ph.D.; Robin Peeters, M.D., Ph.D. and Maryam Kavousi, M.D., Ph.D. Author disclosures are on the manuscript.
The Erasmus Medical Center and Erasmus University in Rotterdam; the Netherlands Organization for Scientific Research; the Netherlands Organization for Health Research and Development; the Research Institute for Diseases in the Elderly; the Netherlands Genomics Initiative; the Ministry of Health Welfare and Sports; the European Commission; and the Municipality of Rotterdam funded the study.
Additional Resources:
- After Oct. 31, view the manuscript online.
- Available multimedia is on the right column of the release link - https://newsroom.heart.org/news/higher-thyroid-hormone-levels-associated-with-artery-disease-and-death?preview=fabd68903c44bc7b8ed7008b92480542
- Irregular heartbeat linked to higher thyroid hormone levels
- Follow AHA/ASA news on Twitter @HeartNews
- For updates and new science from Circulation Research journal follow @CircRES
Statements and conclusions of study authors published in American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect the association's policy or position. The association makes no representation or guarantee as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations and health insurance providers are available at http://www.heart.org/corporatefunding.
About the American Heart Association
The American Heart Association is devoted to saving people from heart disease and stroke - the two leading causes of death in the world. We team with millions of volunteers to fund innovative research, fight for stronger public health policies, and provide lifesaving tools and information to prevent and treat these diseases. The Dallas-based association is the nation's oldest and largest voluntary organization dedicated to fighting heart disease and stroke. To learn more or to get involved, call 1-800-AHA-USA1, visit heart.org or call any of our offices around the country. Follow us on Facebook and Twitter.