Hypothyroidism may lead to impaired driving

People with significant hypothyroidism can experience impaired driving similar to those who are driving when intoxicated by alcohol, a new study finds. The results were presented Sunday at the joint meeting of the International Society of Endocrinology and the Endocrine Society: ICE/ENDO 2014 in Chicago.

Hypothyroidism, insufficient , is very common and has been known to cause impairment of many bodily functions, including brain function. Until now, studies have not sufficiently explored the extent of brain impairment and whether hypothyroid people are safe drivers, said the study's senior investigator, Kenneth Ain, MD, from the University of Kentucky and the Veterans Affairs Medical Center in Lexington, KY.

"We found that hypothyroid patients being tested on a driving simulator had a similar performance to that of drivers with a above the legal limit in the U.S.," said co-author Charles Smith, MD, also of the University of Kentucky. "Physicians should warn their hypothyroid patients to avoid driving until they have been sufficiently treated with thyroid hormone."

In this study, thirty two patients with , who were undergoing preparation for radioactive iodine scanning by stopping thyroid hormone, were evaluated with a battery of neurological and psychological tests, as well as testing on a simulator. They were studied when they were taking thyroid hormone, again when they were off of thyroid hormone, and then finally when they were back on thyroid hormone therapy.

Hypothyroid patients had depression and also showed declines in neurological function that resulted in increased automobile braking times; similar to the performance of drivers with a blood alcohol level of 0.082 g/100 mL. Taking thyroid hormone reversed all of these effects.

"Our results uncover a potential public and personal health hazard regarding impaired hypothyroid drivers," Ain said.

add to favorites email to friend print save as pdf

Related Stories

Gene linked to low IQ

Mar 25, 2014

(Medical Xpress)—Children with both a common gene variant and lower thyroid hormone levels, which occurs in approximately 4% of the population, are four times more likely to have a low IQ, according to ...

Thyroid problems linked to irregular heart rhythm

Nov 28, 2012

People with an overactive thyroid gland (hyperthyroidism) carry a greater risk of developing irregular heart rhythm (known as atrial fibrillation) than those with normal thyroid function, finds a study published on BMJ today. ...

Recommended for you

What exactly is coronavirus?

54 minutes ago

The conflicts in Syria and Iraq are straining public health systems and public health efforts meant to prevent and detect the spread of infectious diseases. This is generating a "perfect storm" of conditions for outbreaks. Among the infections raising concern is Middle East Respiratory Syndrome, caused by a type of coronavirus, which emerged in 2012. ...

Scientists find Ebola virus is mutating

1 hour ago

(Medical Xpress)—Researchers working at Institut Pasteur in France have found that the Ebola virus is mutating "a lot" causing concern in the African countries where the virus has killed over eight thous ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.