Women are twice as likely as men to be diagnosed with Alzheimer’s disease. Researchers have long been looking for the reason why, and it may be due to what’s called ‘cognitive reserve’—brain heft built up through things like education and time in the workforce—which seems to protect against cognitive decline. Older women may be suffering from lack of opportunities when they were young.
Researchers from the ISLAND dementia and cognition research clinic at the University of Tasmania conducted a study following hundreds of older Tasmanians over several years to gain a better understanding.
Associate Professor Jane Alty, Co-Director of the ISLAND clinic and staff specialist in neurology and stroke at Royal Hobart Hospital shared some insights about the study on ABC Radio National’s Health Report.
“We know from other studies that people who have had shorter or lower levels of education, are at higher risk of going on to develop dementia… So, we really wanted to look not just at how does having a longer education reduce your risk of dementia, but is that different for men and women?
“Both men and women who had longer education had better cognitive scores than those with shorter education. But what was interesting is that another measure of cognitive reserve which is innate, so your IQ, your ability to pick up new concepts, that also seemed to be having a different effect in men than women. We could see that men with higher levels of cognitive reserve had a less rapid progression of those changes. So that cognitive reserve was protecting the men’s brains.
“But in women, surprisingly we saw a different pattern… women who had a longer education overall had higher scores, but the rate that they changed over those five years was the same as women that had the lower levels of cognitive reserve.
“What we were seeing is that this cognitive reserve seemed to be having a nice protective effect on the men, as we would expect, but for some reason it just was not having that same protective effect on women.
“We don’t know the reasons for that, but I think what this study is really highlighting is that it’s really important when we’re looking at modifiable risk factors for dementia, that we do look at men and women separately because certainly in our study, looking at cognitive reserve, we were seeing different effects on the men and women for this cognitive reserve protective effect.
“I encourage people who are interested to read the Lancet Commission Dementia Prevention paper which outlines the evidence for the 12 modifiable dementia risk factors that account for about 40% of dementia cases. And these can be broadly split into medical risk factors such as controlling blood pressure and diabetes, and then lifestyle risk factors such as stopping smoking, reducing alcohol intake, doing more physical activity, and so on. I think we probably should be looking at men and women separately in terms of how those risk factors modify risk.
“40% of dementia cases are now attributable to these risk factors, which is good news because it means that through our life, we can start to do something about our risk, particularly those lifestyle factors, which are often quite hard to address, but effectively doing more, moving more, interacting more and so on, really seems to have a good effect”.