'Early menopause increases risk of brain attack'

Earlier onset of the menopause in women may increase their risk of having a brain aneurysm, suggests new research from the US.

A brain (or cerebral) aneurysm is an abnormal bulging of one of the arteries in the brain. These are often only discovered when they rupture, causing a potentially fatal and/or disabling bleed.

Women are more susceptible to having aneurysms than men; fluctuations in the female hormone, oestrogen, have been linked with the development of aneurysms. The occurrence of aneurysms and heart disease rise dramatically after menopause.

High blood pressure, diabetes, high cholesterol and an underactive thyroid can all heighten the risk of a stroke. Meanwhile, the amount of pregnancies and the age at which periods start and stop determine a woman's exposure to oestrogen throughout her life.

Researchers at Mount Rush University Medical Center in Illinois, studied 76 post-menopausal women who had had a cerebral aneurysm - most of these had not ruptured. The women were then questioned about their medical and reproductive histories.

This information was compared with that taken from more than 4,500 women who participated in the 2002 National Institute of Child Health and Human Development Contraceptive and Reproductive Experiences Study.

It was found that the average age at which women in both groups had started the menopause was similar, and that later menopause decreased the risk of aneurysm by 21%.

Researchers also discovered that the use of hormone replacement therapy (HRT) lessened the risk of aneurysm by 77%.

Premature menopause, which occurs before the age of 40, was seen in one in four (26%) of the women who had had an aneurysm, compared with around one in five (19%) of those in the comparison group.

Each successive four-year increase in the age at which a woman went through 'the change' decreased the likelihood of a cerebral aneurysm by about 21%.

The prognosis for ruptured cerebral aneurysms are poor: approximately one in two people who have one are likely to die.

Ten per cent of people die before they reach hospital, and of those who survive, one in five is severely disabled.

Therefore, finding a potential marker may help to catch the condition earlier.

"Loss of oestrogen earlier in a woman's life may contribute to the [development] of cerebral aneurysm," conclude the authors, adding that HRT may protect against this. And they suggest: "These data may identify a risk factor for [the development of this condition] and also a potential target for future therapies," said the research authors.

The research was published online in the Journal of NeuroInterventional Surgery.

[Posted: Tue 12/06/2012]