Testosterone potentially the key to dementia prevention

Monash University scientists are investigating possible links between the hormone testosterone and the prevention of dementia in older women.

Statistics show post menopausal women suffer dementia and memory loss at twice the rate of men and researchers believe their low levels of testosterone may be a contributing factor.

The rate of dementia is expected to increase over the next decade, as the population of over-45 year old women increases by a third to an estimated 5.5 million. (In 2004, there were approximately 3.8 million women aged over 45).

To learn more about the impact of testosterone specifically on the older female brain, Professor Susan Davis and Dr Sonia Davison of Monash’s Women’s Health Program will test a group of Melbourne volunteers over a six-month period.

Professor Davis said testosterone levels in post-menopausal women can fall by half compared to younger women and also report foggy thoughts and memory loss, which can signal the onset of dementia.

"There are many factors that point to dementia, which include symptoms such as a decline in cognitive function, memory loss, problem solving skills and even disorientation," Professor Davis said.

"The brain is filled with testosterone receptors but no-one really knows how testosterone works in the brain. We suspect there could be a strong correlation between low testosterone levels and a decline in female brain function and we want to test this theory."

Dr Davison said the tests would focus on female volunteers who are aged over 45, post-menopausal and also undergoing oestrogen therapy. She said female volunteers will be given the hormone testosterone via a skin spray.

"The spray is a remarkable new development in itself because it is a quick process and easy to apply. The spray creates a patch within the skin when applied. It is an amazing way of receiving a hormone treatment and is less likely to cause allergic reactions in patients," Dr Davison said.

Brain function analysis will be carried out before and after treatment using the latest computerised MRI scanning, that shows brain areas ‘lighting up’ in response to tests of brain function performed.

"By understanding the impact of testosterone on the human brain, the next step is to develop therapies to prevent this condition impacting on the lifestyles of tens of thousands of women across Australia.

(Source: Monash University: March 2008)