The number of people in the United States who develop dementia each year is projected to double in the next 35 years to nearly 1 million annually by 2060. A new study Estimates are, and the number of new cases in black Americans will triple each year.
This increase will be primarily driven by an increasingly aging population, as many Americans are living longer than previous generations. By 2060, some of the youngest baby boomers will be in their 90s and many millennials will be in their 70s. The biggest risk factor for dementia is old age. The study found that the highest risk of dementia occurs after the age of 75, increasing after the age of 95.
study, Published Monday in Nature Medicine.found that adults over age 55 had a 42 percent lifetime risk of developing dementia. This is significantly higher than previous lifetime risk estimates, which the authors attribute to more recent information about Americans’ health and longevity and the fact that their study population was more diverse than previous studies. which consisted mainly of white people.
Some experts said the new lifetime risk estimate and projected increase in annual cases may be overstated, but they agree that dementia cases will increase in the coming decades.
“Even if the rate is significantly lower than that, we will still have a large increase in the number of people and an increase in the family and societal burden of dementia simply because of the increase in the number of older people, both in the United States and around the world,” said Dr. Kenneth Langa, a professor of medicine at the University of Michigan who has researched dementia risk and was not involved in the new study.
Dementia is already taking a heavy toll on American families and the nation’s health care system. More than six million Americans are currently living with dementia. About 10 percent of people age 65 and olderresearch has found. Experts say dementia causes more than 100,000 deaths each year in the United States and accounts for more than $600 billion in care and other costs.
Dr. Joseph Koresh, director of the Optimal Aging Institute at New York University’s Grossman School of Medicine and lead author of the study, said about 12 million Americans will suffer from dementia in 2060 if the new projections hold. 100 researchers in 10 universities.
The study reinforces the urgent need to try to prevent or slow the onset of dementia, the authors and other experts said. Their main recommendations are to improve people’s cardiovascular health with medication and lifestyle changes. Increasing efforts to prevent and treat stroke, which can lead to dementia. And encourage people to wear hearing aids, which appear to help stave off dementia by allowing people to engage more socially and cognitively.
“One needs to look at the enormity of the problem,” said Alexa Beiser, a professor of biostatistics at the Boston University School of Public Health, who was not involved in the new study but served as an independent reviewer for the journal. Reviewed. “It’s huge, and it’s not evenly distributed among people,” Dr. Bezer said, adding that the study found a disproportionate risk for black Americans.
Researchers examined more than three decades of data from a long-running study of people’s health in four communities in Maryland, Mississippi, Minnesota and North Carolina. About 27 percent of the 15,000 participants were black, primarily from Jackson, Miss., Dr. Koresh said. The analysis, which was funded by the National Institutes of Health, focused on black and white participants because there were no more participants from other racial and ethnic groups, the authors said.
The study estimates that the number of new annual cases among black people will increase from about 60,000 in 2020 to about 180,000 in 2060. The main reason for the tripling of new cases in this population is that a percentage of black Americans are living longer. Dr. Koresh said it is growing faster than white people.
In the study, black participants also developed dementia at a younger age than white participants and had a higher lifetime risk.
“I don’t know that we fully understand it, but at least some of the contributing factors are that vascular risk factors are more common,” Dr. Koresh said of high blood pressure, diabetes and high cholesterol dementia risk. Increase the Low socioeconomic status and education levels among study participants may have played a role, as well as structural racism affecting health, he said.
Predicting the risk of dementia is complicated for several reasons. The causes of dementia are varied and often not fully understood. The types of dementia also vary and may overlap with each other. The new analysis, like many other studies, did not try to predict how many people would develop Alzheimer’s disease, the most common type of dementia. That’s because many experts believe that aspects of Alzheimer’s can coexist with vascular dementia, and that both conditions can be caused by cardiovascular problems, Dr. Koresh said.
Several studies in the United States and globally have found a higher percentage of dementia cases in older adults. There has been a decline in recent yearsmost likely due to better treatment of cardiovascular problems and a more educated population, as education can improve mental resilience and overall health.
Experts and authors said that the reduction does not contradict the new research, as the research assessed and projected current levels of dementia risk over people’s lifetimes. It’s possible that positive changes—healthier behaviors and better treatments for conditions like diabetes and stroke, for example—could lower risk rates at any age in the coming decades, but new cases each year. The number will still increase from the current number. 514,000, experts said, due to a growing population of older people.
“Whether it’s a million people or 750,000 people a year, there’s going to be a lot of people, and the longer people live, the more dementia is going to develop,” said Dr. Beiser, who has worked on . First study Various patients have been found to be under-estimated.
The study also found that women have a higher lifetime risk of dementia than men – 48 percent compared to 35 percent. Dr Koresh said this was mainly because the women in the study lived longer. “The risk of developing dementia by their 95th birthday is higher because more of them make it closer to their 95th birthday,” he said.
Dr. Langa said other researchers are trying to figure out whether there may also be biological differences that increase women’s risk, possibly “hormonal environments in the body or even possible genetic differences that make women more vulnerable than men.” can affect their brains in different ways.”
Another high-risk group was people with two copies of the gene variant APOE4, which greatly increases the risk of Alzheimer’s disease and develops it at a younger age than people without the variant. In the study, people with two copies of APOE4 had a 59 percent lifetime risk of dementia compared to 48 percent for people with one copy and 39 percent for people without the variant.
The analysis used health data from the Atherosclerosis Risk in Communities Study (known as ARIC), which followed people aged 55 and older from 1987 to 2020.
The researchers used several methods to determine if and when participants developed dementia. About a quarter of cases were diagnosed in person through neuropsychological testing, while others were identified through hospital records or death certificates or telephone reviews. Each method has limitations, which may lead to over- or under-estimation of the actual number of dementia patients, experts said.
The study found that the risk of dementia at age 75 was about 4 percent. At 85, it was 20 percent; And at 95 it was 42 percent. The researchers applied risk percentages to population estimates from the census to estimate future annual dementia diagnoses.
To reduce your chances of developing dementia, experts and study authors urge taking steps to address known risk factors such as diabetes, high blood pressure and hearing loss. A recent report by Lancet Commission on Dementia listed 14 risk factors that could be improved and concluded that “half of the risk of dementia is preventable and it is never too early or too late to address the risk of dementia,” Dr. Koresh said. .
Experts recommend such measures rather than seeking them out New drugs for Alzheimer’s, which appears to be able to modestly slow cognitive decline only in the early stages of the disease and carries safety risks.
“Because of their relatively limited efficacy, I don’t think you’re going to get a huge lifetime risk reduction from this,” Dr. Langa said. New drugs. “I think we will get more benefit from some of these public health and lifestyle interventions that generally improve health and reduce the risk of dementia over time.”