- The incidence of dementia is rising at an alarming rate.
- While it's primarily diagnosed over age 50, it starts decades earlier.
- Modifying behavior to avoid a handful of known risk factors can help reduce the chance of getting dementia.
A multi-university study lead by the University of Melbourne and the University of Washington has found that the number of people living with dementia worldwide shot up from 20.2 million in 1990 to 43.8 million in 2016. The researchers analyzed data from the Global Burden of Disease Study 2016, publishing their results in The Lancet Neurology.
When dementia begins
The majority of diagnoses are in people over 50, with the number of cases doubling every five years beyond that age. The age range, however, seems more narrow than it really is, since it’s believed that dementia begins at least 20 to 30 years before the symptoms that lead to a diagnosis become obvious.
The report lists potential triggers during those early decades. “In our study,” says the report, “22.3 per cent (11.8 – 35.1 per cent) of the total global disability-adjusted life years lost due to dementia in 2016 could be attributed to the four modifiable risk factors:
- being overweight
- maintaining high blood sugar
- consuming a lot of sugar sweetened beverages
Study lead author Cassandra Szoeke tells The Melbourne Newsroom that further study of cognition over those earlier decades will be necessary to understand the development of dementia more fully. “When you look over decades there are so many exposures that impact on our health,” says Zoeke, “you need to account for all these things or you could miss a factor that is crucial in the development of disease.” Still, even with what we know now, she adds, “Already the importance of these risks in allowing us to prevent or delay dementia is clear. The paper noted that changes in risk factor exposure over time as we become healthier might account for several cohort studies documenting a reduction in age-specific incidence rates in their study populations.”
(Tan Yen Yi/Shutterstock)
The study projects that by 2050 we can expect to see 100 million people living with dementia. As a result, says Zoeke, “The paper states that to support our community, we will need a larger workforce of trained health professionals, as well as planning and building facilities and community-based services which support improved quality of life and function.”
What the researchers would like to see as the impact of their study is clear: “We need to enhance the quality of life and function of people living with cognitive impairment and focus on preventing further cognitive decline. This will need a co-developed community-wide approach with well-developed services and an even greater network of trained health professionals.” On top of that, we’ll need to learn all we can about the risk factors and, armed with a fuller understanding of the mechanisms involved, get better at reducing the prevalence of this life-stealing condition.