Nearly a third of Americans 65 and older have some level of cognitive impairment — including 10 percent who have dementia, according to a national study that found Black and Hispanic/Latino Americans at greater risk of experiencing a loss of brain function as they age.
“This study is representative of the population of older adults and includes groups that have been historically excluded from dementia research but are at higher risk of developing cognitive impairment because of structural racism and income inequality. If we’re interested in increasing brain health equity in later life, we need to know where we stand now and where to direct our resources,” lead study author Jennifer J. Manly, a professor of neuropsychology at Columbia University, said in a statement.
Although dementia and mild cognitive impairment are known to be common in the United States, the researchers note that their study is the first in 20 years to provide an accurate, up-to-date measure of the national prevalence of cognitive impairment. The Centers for Disease Control and Prevention, for example, cites a 2011 statistic for its estimate that more than 16 million Americans are living with cognitive impairment, a condition that affects memory, thinking and everyday decision-making.
5 key findings on cognitive impairment
- Age was the strongest indicator of dementia, ranging from a low of 3 percent (65 to 69) to a high of 35 percent (90 and older).
- Black Americans (65 and older) had the highest rate of dementia, at 15 percent, compared with 10 percent of Hispanic/Latino Americans and 9 percent of white Americans.
- Hispanic/Latino Americans (65 and older) had the highest rate of mild cognitive impairment, at 28 percent, compared with 22 percent of Black Americans and 21 percent of white Americans.
- Educational attainment is also a key indicator. Those who did not finish high school were more likely than those with at least a college degree to have dementia (13 percent versus 9 percent) or mild cognitive impairment (30 percent versus 21 percent).
- Men and women have similar rates of dementia and mild cognitive impairment.
“Our results confirm that the burden of cognitive impairment and dementia in the U.S. is associated with increasing age. As longevity increases and as the so-called baby boomer generation ages, the burden of cognitive impairment is projected to increase in the decades ahead for individuals, families and programs that provide care and services for people with dementia,” the study researchers wrote.