More People Are Living Long Enough to Get Dementia
New cases are projected to double to 24 million a year by 2050, with the fastest growth in poorer countries that are now growing older.
Global News Podcast · Annual dementia cases could double by 2050More people are living to the ages when dementia is common. That is why the number of new cases is expected to keep climbing.
That is the explanation from Professor Henry Brodaty, a dementia researcher and coauthor of a major new study from the Center for Healthy Brain Ageing at the University of New South Wales in Australia. He said, "The epidemic's not of dementia, it's of aging."
The math is stark. According to Brodaty, "The rate of dementia doubles every five years after the age of 65." That means the risk for an 80-year-old is far higher than for a 70-year-old, and the risk for someone over 90 is higher still. As Brodaty explained, "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."
Dementia develops slowly. It often starts with gradual declines in memory and social skills, then can move on to the brain areas that control breathing and swallowing. It ranks among the leading causes of death globally, and its rise is straining health systems in many nations.
What is changing is how many people reach those high risk ages. In Britain, about 20% of the population is now over 65, and in Australia the share is about 17%. Brodaty noted, "But in low and middle income countries, that aging is just starting to catch up now." The study suggests those nations will see especially steep rises in dementia cases in the years ahead.
Overall, the study warns that new dementia diagnoses worldwide will double by 2050, to 24 million per year. That does not mean something new is causing dementia, but that success at keeping people alive longer means there will be more of it.
Questions people ask
Why does the risk rise so steeply with age?
Age allows damage to accumulate in the brain over decades, including damage to blood vessels and to nerve connections. The brain also becomes less able to repair itself and to compensate for losses. That is why the same person faces much higher odds at 85 than at 65.
If aging is the cause, can people do anything to lower their risk?
Age and genes cannot be changed, but many health habits can lower the odds or delay onset. Doctors point to education, regular exercise, and treatment of high blood pressure and high cholesterol. Social activity, hearing care, and avoiding smoking and heavy drinking are also linked to lower risk.
Why will low and middle income countries be hit hardest?
Those countries have younger populations today but life expectancy is rising as child mortality falls and medical care improves. That means a large generation is about to enter the high-risk years after 65. Health systems there often have fewer hospitals, specialists, and elder-care services to handle the surge.