Underactive thyroid not linked to memory problems

Underactive thyroid not linked to memory problems
New findings contradict previous research suggesting that poor thyroid function might be tied to dementia.

(HealthDay)—Hypothyroidism, a condition that causes low or no thyroid hormone production, is not linked to mild dementia or impaired brain function, a new study suggests.

Although more research is needed, the scientists said their findings add to mounting evidence that the disorder is not tied to the memory and thinking problems known as "."

Some prior evidence has suggested that changes in the body's endocrine system, including , might be linked to Alzheimer's disease and other forms of dementia, said researchers led by Dr. Ajay Parsaik, of the University of Texas Medical School in Houston.

Mild cognitive impairment, in particular, is thought to be an early warning sign of the memory-robbing disorder Alzheimer's disease, the study authors said in a university news release.

In conducting the study, Parsaik's team examined a group of more than 1,900 people, including those with mild and more severe cases of hypothyroidism. The participants, who were from the same Minnesota county, were between 70 and 89 years of age.

The study showed that memory and thinking problems occurred at about the same rate regardless of thyroid function. Impairments in occurred in 16 percent of participants with normal thyroid function, 17 percent of patients with more severe hypothyroidism and 18 percent of people with mild hypothyroidism.

No association between hypothyroidism and mild brain impairment was found, the researchers said, even after they took into account the participants' age, gender, body-mass index (a measurement of body fat based on height and weight) and other health problems.

One expert said the final word on this issue might still be yet to come, however.

Dr. Spyros Mezitis, an endocrinologist at Lenox Hill Hospital in New York City, said the study had a "robust" design. But because the results conflict with those of prior studies, they "need to be validated in research in separate settings" and with a trial that follows patients over time.

"The practicing physician should continue testing thyroid function in the setting of [memory and thinking] decline and treating clinical ," Mezitis said.

The study was published online Dec. 30 in the journal JAMA Neurology.

More information: The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about hypothyroidism.

Related Stories

Are concussions related to Alzheimer's disease?

Dec 26, 2013

A new study suggests that a history of concussion involving at least a momentary loss of consciousness may be related to the buildup of Alzheimer's-associated plaques in the brain. The research is published in the December ...

Recommended for you

Continuing the quest for better stroke therapies

1 hour ago

Helping people recover from the debilitating effects of a stroke is an immensely complex challenge that requires deep knowledge of neurophysiology as well as effective therapy. Advancing such knowledge to improve therapeutic ...

At last, hope for ALS patients?

4 hours ago

U of T researchers have found a missing link that helps to explain how ALS, one of the world's most feared diseases, paralyses and ultimately kills its victims. The breakthrough is helping them trace a path to a treatment ...

User comments