The study, published online first in the Journal of NeuroInterventional Surgery, found that the younger a women is during menopause, the more likely she is to have a cerebral aneurysm.
A cerebral aneurysm occurs when a blood vessel in the brain enlarges and is usually only discovered once it ruptures, causing a potentially lethal and/or disabling bleed.
According to the researchers, men are less likely to experience cerebral aneurysms than women. The development of aneurysms have been associated with fluctuations in the female hormone oestrogen and after menopause the incidence of aneurysms, along with heart disease, increase significantly.
The researchers enrolled 76 postmenopausal women who had had a brain aneurysm to participate in the study. In the majority of cases the womens' aneurysms had not ruptured. The team then asked participants questions regarding their reproductive and medical histories.
The age at which periods start and stop, as well as the number of pregnancies a women experiences determine lifetime exposure to oestrogen, while diabetes, high cholesterol, hypothyroidism, and hypertension can all increase the risk of stroke.
The researchers then compared the information from study participants to information taken from more than 4,500 women who took part in the 2002 National Institute of Child Health and Human Development Contraceptive and Reproductive Experiences Study. The team then matched all the information for educational attainment and age.
According to the researchers, the average age at which women experience menopause was comparable in both groups. They found that women who went through menopause at an older age were 21% less likely to have an cerebral aneurysm. In addition, those who used hormone replacement therapy (HRT) were 77% less likely to experience an aneurysm.
26% (1 in 4) of the women who had experienced an aneurysm started menopause before the age of 40 vs. 19% of women in the comparison group.
Furthermore, the team found that each successive four year increase in the age at which a woman experienced menopause reduced the risk of having a brain aneurysm by approximately 21%. The researchers found that although smoking did not increase the risk, alcohol consumption was of borderline significance.
Around 1 in 2 people who have a ruptured cerebral aneurysm are likely to die, while 1 in 10 die before they arrive at hospital. Furthermore, of those who survive, 1 in 5 are left severely disabled. Therefore, finding a potential marker may help medical professional identify the condition sooner.
The researchers conclude:
"Loss of oestrogen earlier in a women's life may contribute to the [development] of cerebral aneurysm." They note that adding HRT may protect against this. They explain: "These data may identify a risk factor for [the development of this condition] and also a potential target for future therapies."
Written By Grace Rattue