Why Women Face Higher Alzheimer’s Risk (And The One Thing That Lowers It) | Dr Tommy Wood

0:00Welcome to Live Well Be Well, a show to help high performers improve their health and well-being.

0:11Dementia as a whole mostly affects women more than men. Am I right in saying that? Alzheimer's disease, yes. So around two-thirds of the individuals impacted by Alzheimer's disease are women. Vascular dementia is about 50-50. Oh really? So the total dementia burden is greater in women, but it depends on the type of dementia. Do you know why that is? Because, I mean, obviously, I've been really interested about all the work that you're doing on making sure we've got to stimulate the mind. I remember when we last spoke, you told me that learning a new language is really important. My dyslexic brain got very stressed about that part.

0:46But, you know, making sure that you're keeping up new daily tasks, which I want to talk about, especially with your new book that's coming out, which even the title the stimulated mind tells you that we've got to keep simulating it but it made me think about women previously when they you know women used to be housewives and look after children be caretakers doing everything at the household and maybe they weren't as stimulated as the men in the family who were going to work and having to provide do you think there's like any correlation to what women were like in previous generations it's a short paragraph i try and make that case in the book so one thing that people don't necessarily appreciate because every time we talk about dementia it's always doom and gloom and the burden of dementia is expected to double or triple in the next few decades largely just because we're living longer but people don't realize that actually the age specific incidence or risk of dementia has decreased over the last six or seven decades.

1:50So if you look at what your risk of getting dementia was at 60 or 70 years old in the 30s or 40s, 1930s, 1940s, that risk has steadily been declining. And they've shown that in multiple countries, in multiple studies. And there are a few reasons for why that could be the case. One is nutrition has improved. A big thing when you sort of read these studies, the author does hypothesize that part of it is because we've become really good at treating heart disease and the risk factors for heart disease overlap with the risk factors for dementia but one thing that i noticed when i was looking at all these data and i'll tell you about one specific study that really made me think about this is that it's only really been since sort of 1960s 1970s that women have really entered the workforce have been have been able to get access to these higher, more complicated, more stimulating jobs, as well as being able to get better access to education.

2:45And that's true in the US, in the UK, but also around the world in general. And as women have gained greater access to education, their cognitive function, when you measure on classic cognitive function tests, has improved and their risk of dementia has declined. So there's no randomized trial that tells you that this is the case, but the data certainly seem to suggest that. One study that really sort of opened my eyes on a number of fronts of this was run out of the University of Washington, which is where I now work, called the Seattle Longitudinal Study, run by Warner Shiai. And it was one of the first studies where they didn't just take a whole group of people and measure their cognitive function and look at your average cognitive function by age, which is what a big population study might do.

3:31It was one of the first study is to take the same people and measure their cognitive function regularly over decades. So he got people that came in every seven years, and some people were in this study for several decades. So there are people from teens up to more than 100 years old by the end of the study, and it ran for 40 or 50 years. And one of the early studies they did from this huge collection of data that they got looked at something they called environmental complexity. So it was, you know, this is beginning in the 50s and the cognitive function test was sort of derived in the 50s and 60s.

4:12And so we have much more detailed ways of measuring those things now. One of the first studies they did, looking at all these data from this study, looked at something called environmental complexity. And this is something that we can study in a much more detailed way now because this you know this study was started in the 1950s but what they did is they looked at the the way that people's brains were stimulated and how they engaged with the environment so that included their jobs included their level of education included other types of social interaction and they found that those with the highest amounts of what they call environmental complexity, had the greatest likelihood of maintaining stable cognitive function for decades into the future.

5:00And this study actually showed that on average, people maintained cognitive function from their 50s into their 80s. It was not this rapid decline that everybody expected. And it was data from the Seattle Longest Tunnel study that was used or partly used to raise the retirement age in the US in the 1980s, because they showed that actually people could maintain, the average was to maintain cognitive function into your 80s, which is not necessarily what people expect. And this was published back in the sort of 70s and 80s. But when looking at environmental complexity, one of the groups that had the lowest environmental complexity and also the greatest declines in cognitive function over time were housewives.

5:43and that this is no comment on people who choose to take that type of role right it's just that if you're not getting access to education or getting access to these other cognitively stimulating environments that come through work you might be socially isolated because you spend all day at home alone um and you know this was something this was a role that was largely filled by women back in the 1950s and 60s and so i i think that you're right i think that the fact that this has changed over the last few decades is part of the reason why we've seen dementia decline. And it's not the total burden of dementia that's declining.

6:21It's that at 60 years old, what's your risk of getting diagnosed with dementia? At 70 years old, what's your risk of getting diagnosed with dementia? At any given age, your risk is lower, but because we're living longer and, you know, unfortunately the health of the population is now getting worse again, risk is starting to increase but I think that the fact that the role of women in society has changed has actually contributed to benefit for their brains and overall lower risk of dementia at least over the past few decades. Thanks so much for listening to hear the full episode there's a link in the description.