Thyrotropin levels associated with Alzheimer's disease risk in women

Jul 28, 2008

Women with low or high levels of the hormone thyrotropin, which affects thyroid gland function and thyroid hormone levels, appear to have a higher risk of developing Alzheimer's disease, according to a report in the July 28 issue of Archives of Internal Medicine.

A clinically detectable over- or under-active thyroid has long been recognized as a potentially reversible cause of cognitive (thinking, learning and memory) impairment, according to background information in the article. Previous studies have examined whether levels of thyrotropin, a hormone that is secreted by the pituitary gland and helps regulate thyroid gland function, is associated with cognitive performance in individuals with normal thyroid function. However, results have been inconsistent.

Zaldy S. Tan, M.D., M.P.H., of Hebrew SeniorLife, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, and colleagues measured thyrotropin levels in 1,864 individuals (average age 71) without cognitive problems between 1977 and 1979. Participants—part of the community-based Framingham Study—were assessed for dementia at that time and again every two years.

Over an average of 12.7 years of follow-up, 209 participants developed Alzheimer's disease. After adjusting for other related factors, the researchers found that women with the lowest (less than 1 milli-international unit per liter) and highest (more than 2.1 milli-international units per liter) levels of thyrotropin had more than double the risk of developing Alzheimer's disease. However, no relationship was observed between thyrotropin levels and Alzheimer's disease risk in men.

"Whether altered thyrotropin levels occur before or after the onset of Alzheimer's disease, the neuropathologic mechanism is unclear," the authors write. Changes in the brain caused by Alzheimer's disease may cause a reduction in the amount of thyrotropin released or changes in the body's responsiveness to the hormone. Alternatively, low or high thyrotropin levels could damage neurons or blood vessels, leading to cognitive difficulties.

Source: JAMA and Archives Journals

Explore further: Why alcoholism saps muscle strength

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Why alcoholism saps muscle strength

1 hour ago

Muscle weakness is a common symptom of both long-time alcoholics and patients with mitochondrial disease. Now researchers have found a common link: mitochondria that are unable to self-repair. The results will be published ...

Scientists make critical end-stage liver discovery

2 hours ago

(Medical Xpress)—A team of researchers in the University of Arizona's College of Pharmacy has discovered a molecular pathway that could be key to creating new therapeutics that would slow or even reverse ...

Leeches help save woman's ear after pit bull mauling

Apr 18, 2014

(HealthDay)—A pit bull attack in July 2013 left a 19-year-old woman with her left ear ripped from her head, leaving an open wound. After preserving the ear, the surgical team started with a reconnection ...

User comments : 0

More news stories

Why alcoholism saps muscle strength

Muscle weakness is a common symptom of both long-time alcoholics and patients with mitochondrial disease. Now researchers have found a common link: mitochondria that are unable to self-repair. The results will be published ...