 |
|
Thyrotropin levels associated with Alzheimer's disease risk in women
July 29, 2008Women 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, one of the JAMA/Archives journals.
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.
"In conclusion, low and high thyrotropin levels were associated with an increased risk of incident Alzheimer's disease in women but not in men," the authors conclude. "These findings should be considered hypothesis-generating and should be validated in other populations before clinical conclusions are drawn."
JAMA and Archives Journals
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.
"In conclusion, low and high thyrotropin levels were associated with an increased risk of incident Alzheimer's disease in women but not in men," the authors conclude. "These findings should be considered hypothesis-generating and should be validated in other populations before clinical conclusions are drawn."
JAMA and Archives Journals
Thyrotropin levels may be associated with coronary heart disease mortality in women
Women with increasing levels of thyrotropin within the normal range appear to have a higher risk of fatal coronary heart disease, according to a report in the April 28 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Study suggests anesthetic agent may have rapid antidepressant effects
A single intravenous infusion of a drug known as ketamine, which is a general anesthetic agent, may relieve symptoms of depression within two hours and remain effective for up to one week.
Glycoprotein hormone receptors
We have aspired at understanding and further dissecting the molecular mechanism of activation of the Glycoprotein hormone receptors (GpHr), members of the G protein coupled receptor (GPCR) superfamily.
Thyroid-cancer test reveals recurrence early
A blood test for thyroid cancer can detect persistent or recurrent disease even before doctors can find any trace of a tumor, according to a new study. The findings suggest that people treated for the disease should be examined regularly for early signs of recurrence.
Mild Hyperthyroidism Linked To Increased Mortality
Elderly people with slightly raised thyroid hormone concentrations-but who do not have overt thyroid disease-could be at an increased risk of death from cardiovascular disease, suggest authors of a study in this week's issue of THE LANCET. Low blood concentration of the hormone thyrotropin is a marker of thyroid-gland overactivity (hyperthyroidism); hyperthyroidism is associated with metabolic disorders, and cardiovascular disease. Low thyrotropin concentrations in combination with normal thyroid-hormone concentrations describe individuals with mild or subclinical hyperthyroidism, which is common in elderly people and in individuals with a history of thyroid disease. Jayne Franklyn and colle
More Thyrotropin Current Events and Thyrotropin News Articles
| © 2008 BrightSurf.com |