Annual dementia cases could double by 2050

Nick Miles (0:00)

This is The Global News Podcast from the BBC World Service. I'm Nick Miles, and in the early hours of Tuesday, the 13th of October, these are our main stories. The number of people diagnosed every year with dementia is predicted to double by 2050, according to a major international study. As Houthi strikes continue to hit Saudi Arabia from Yemen, we hear from our correspondent traveling with Yemeni government troops who are trying to push the militants back. And the US. Democratic Congresswoman, Ilhan Omar, has accused President Trump of political intimidation after federal immigration agents raided her Washington home.

Also in this podcast, $276 million in donations since July. We find out what Elon Musk has to gain from bankrolling Republicans in the US midterm elections and...

Dzergy Kocic (0:55)

This year's vote was a vote for Europe, for rejoining Europe. I think most people were fed up with being the black sheep.

Nick Miles (1:05)

It's six months since Hungary's nationalist Fidesz party was ousted from power. So what's changed under the new government?

We begin with an important new study about a condition that is a major cause of deaths around the world. Dementia develops slowly. Symptoms like a decline in memory and social skills start gradually, but can then spread to areas that control those vital physical functions like breathing and swallowing. In many countries around the world, the rise of dementia is putting enormous pressure on health care systems. Now, one of the most comprehensive studies on dementia has warned that by 2050, the number of people being newly diagnosed every year will double to 24 million. It suggests that low and middle-income nations, where average ages are now on the rise, will show particularly rapid increases in dementia in the coming years. Professor Henry Brodaty is co-author of the study that was carried out by the Centre for Healthy Aging at the University of New South Wales in Australia.

Henry Brodaty (2:11)

In countries like the UK and Australia, where I'm from, particularly in the UK, I think you're already about 20 percent of your population over 65 We're at about 17 percent. But in low and middle-income countries, that aging is just starting to catch up now. The rate of dementia doubles every five years after the age of 65

So the more people you have who are older, particularly people who are over 80 or 90, then you have a much more rapid increase. The epidemic is not of dementia, it's of aging.

Nick Miles (2:38)

But there is also an issue with women being disproportionately vulnerable to this disease. Yes. Why is that?

Henry Brodaty (2:45)

That's really interesting. There may be social and environmental reasons as well as biological reasons. So the social reasons, particularly in years gone by, is women had less education, they had less opportunity to be engaged in occupations which were intellectually demanding and therefore build up cognitive reserve. They were also more likely to have obesity in midlife and hypertension in midlife which are risk factors for dementia and also more likely to have depression, which is also another risk factor. On the biological side, it may be that hormones have a, the estrogens have a neuroprotective action in the brain that's been postulated.

And it may be that women have more of the toxic protein called the amyloid beta protein in the brain. And amyloid beta protein is the main culprit for Alzheimer's disease and the new treatments now available are targeting that protein. We know that women who had their ovaries out at a younger age, before menopause, who then go on to HRT, are less likely to get Dementia later in life.

Nick Miles (3:46)

What are the social and financial costs of the overall increase in Dementia, numbers that we can expect over the next 25 years?

Henry Brodaty (3:54)

Currently, it's estimated we spend 1.3 trillion US dollars on Dementia worldwide.

And even by the end of the decade, that will be 2 trillion US dollars. So Dementia is a big ticket item.

Nick Miles (4:07)

We're all forewarned by reports like this. What can be done about it?

Henry Brodaty (4:12)

We know that about 45 percent of the risk of Dementia, environmentally modifiable factors, things that we can do something about individually and also as a society. So for example, we know that people with more education build up more cognitive reserve, which is a buffer against the pathology that may build up in the brain as we age. People who exercise more are less likely to develop dementia. People who don't have hypertension or if they do have high blood pressure, have it treated and for every year of treatment, that reduces the risk. Ditto for high cholesterol or lipids.