When it comes to your risk of getting dementia, there's good news and bad news (see “bad news for boomers,” below). First the positive: A new study reveals a 13 percent decline per decade in memory-robbing diseases over the past three decades. To arrive at that finding, researchers analyzed data from seven large studies, involving 49,202 adults, ages 65 and older, in the U.S. and Europe, and examined changes in the incidence of dementia between 1988 and 2015. The sizeable decline, they discovered, occurred in both men and women, though it was slightly more pronounced in men.
This means that “if you're 65 now, your risk of getting dementia between 66 and 70 is lower than it was in 1970 or 1990,” explains study coauthor Sudha Seshadri, M.D., a professor of neurology and director of the Glenn Biggs Institute for Alzheimer's & Neurodegenerative Diseases at the University of Texas Health Sciences Center in San Antonio. As the study authors note, if this trend continues in Europe and North America into the coming decades, 15 million fewer people will develop dementia by the year 2040.
What's responsible for fewer numbers of older adults likely suffering a memory-robbing brain disease? “There are a lot of factors that are likely at play, but one thing we can take out of the steady decline in the last three decades is that we are doing something right,” says study coauthor Lori Chibnik, an assistant professor of epidemiology at the Harvard T.H. Chan School of Public Health. “Many of the changes over the last 30 years that might have played a vital role in reducing the risk of dementia [were] directed at cardiovascular risk management, such as blood pressure control and lifestyle changes, as well as smoking cessation and increase in exercise.” In addition, the reduced incidence of stroke and better outcomes after stroke that have occurred in the U.S. and Europe likely contributed to the decreasing dementia trend, Seshadri says.
Despite this significant step in the right direction, an estimated 50 million people worldwide have dementia, and nearly 10 million new cases are identified each year, according to the World Health Organization. There are more people than ever with dementia because people are living longer, which means that more are reaching the ages when this condition is increasingly likely to occur. What's more, people who have dementia are living longer, Seshadri explains. “Overall, the burden of dementia on communities and families continues to increase."
Bad news for boomers: Results of another new study on cognitive function
Among the groups that may be at higher risk for dementia in the future: boomers. That's according to a study in the July 29, 2020, issue of The Journals of Gerontology, Series B. Using data from 30,191 participants in the 1996–2014 “Health and Retirement Study,” this study measured cognitive functioning across seven decades of generations, from the Greatest Generation to the boomers. It turns out that cognitive functioning improved from the Greatest Generation (those born between 1890 and 1923) to the “war babies” (those born between 1942 and 1947) but then declined significantly with boomers.