Study: No ill effects from mild thyroid disease

Testing is easy, but treating borderline levels might not make a difference.

By Victoria Stagg Elliott, AMNews staff. Dec. 25, 2006.

Giving weight to the argument that no action may be best for addressing subclinical thyroid dysfunction among the elderly, a study published in the Annals of Internal Medicine found no connection between this condition and mood disorders or cognitive deficiencies in those older than 65.

"There is no clinically relevant association between minor thyroid abnormality and cognition, depression or anxiety," said Lesley Roberts, PhD, lead author of the Oct. 17 piece and behavioral sciences lecturer in the Dept. of Primary Care and General Practice at the University of Birmingham, England. "In light of these findings, we do not advise screening or treating patients with subclinical dysfunction purely to prevent mental decline."

Researchers assessed the emotional state and thyroid function of 5,865 patients receiving care from primary care practices in and around Birmingham. The goal was to increase the body of evidence that could answer the longstanding question of the value of routine thyroid function testing.

It has long been known that overt thyroid problems, which produce significant symptoms, need to be diagnosed and treated, but benefits of routine screening and treatment for those with asymptomatic mild thyroid problems are unclear. The U.S. Preventive Services Task Force guidelines say insufficient evidence exists to recommend for or against routine thyroid disease screening for adults. But the American Thyroid Assn. recommends that screening begin at age 35 and be repeated every five years. "This is one of the most controversial areas in all of endocrinology, and whether primary care should be screening older people for this is all over the map," said David S. Cooper, MD, president of the group.