As the aging population in the United States increases, projections indicate that 1 million new dementia patients will emerge each year. This figure corresponds to twice the current incidence rate, prompting calls for revisions in public health strategies to alleviate the social expenses associated with the rise in dementia patients.
A research team led by NYU Grossman School of Medicine published on the 13th (local time) in the international journal Nature Medicine that the number of patients diagnosed with dementia in the U.S. is expected to reach 1 million annually by 2060. The researchers noted, "The number of people diagnosed with dementia in the U.S. is expected to double over the next 35 years" and emphasized the need for a new public health strategy aimed at mitigating dementia risk across diverse population groups and promoting healthy aging.
As one grows older, it takes longer to recall someone's name or remember where one left their keys. Scientists consider this to be a natural part of the aging process. However, dementia, which involves a gradual loss of memory, language abilities, and cognitive function, is not classified as normal aging.
Age is the most significant risk factor for developing Alzheimer's disease and vascular dementia. As society ages, the number of dementia patients is bound to increase. 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. According to the Framingham Heart Study by the National Heart, Lung, and Blood Institute (NHLBI), 14% of American men and 23% of American women are likely to develop dementia at least once in their lifetime.
The risk of developing dementia increases with age. The lifetime risk of developing dementia, which indicates a person's likelihood of experiencing dementia, is used as a public health indicator that influences health policies and public awareness. The research team led by Joseph Corsi at NYU analyzed health data records from 10,543 healthy white and black individuals aged 55 and older living in Maryland, Mississippi, Minnesota, and North Carolina over a span of 33 years (1987-2020).
The analysis indicated that the lifetime risk of dementia for American adults aged 55 and older is 42%. This means that if people live longer, 4 out of 10 are likely to develop dementia. The risk of dementia sharply increases after age 75. The likelihood of developing dementia before age 75 is only 4%, whereas it rises to 20% between ages 75 and 85, and to 42% between ages 85 and 95.
The risk of developing dementia over a lifetime is higher for women (48%) than for men (35%). Professor Corsi explained that women generally live longer than men, which increases their risk of dementia. The results also indicated that black individuals (44%) have a higher risk of developing dementia than white individuals (41%). The research team projected that as the proportion of long-lived black individuals increases, the number of new dementia cases among black Americans is expected to triple by 2060. Black individuals tend to develop dementia at a lower average age and exhibit a higher lifetime risk of this condition.
It has also been confirmed that elderly individuals with genes involved in transporting cholesterol and fats in the bloodstream have a higher risk of developing dementia. The APOE ε4 gene variant is a risk factor that increases the likelihood of developing dementia, including Alzheimer's disease. The APOE4 genotype is found in about 20% of individuals without dementia but is observed in over 50% of dementia patients. Particularly, individuals with two copies of the APOE4 genotype almost invariably develop Alzheimer's disease. Research to date shows that about 25% of the global population carries one copy of the APOE4 genotype, and 2-3% carry two copies. In this study, individuals with two APOE4 genotypes were found to have a 59% risk of developing dementia, while those with one copy had a 48% risk, and those without the gene had a 39% risk. The research team anticipated that, in summary, the number of new dementia diagnoses in the U.S. will increase from approximately 514,000 in 2020 to about 1 million by 2060.
According to the study, over 6 million people in the U.S. are currently living with dementia, accounting for about 10% of those aged 65 and older. Professor Corsi stated, "If the new projections are accurate, about 12 million Americans will be living with dementia by 2060."
These results indicate a significantly higher figure than previously published estimates of dementia risk. The researchers pointed out that the risk of dementia among Americans has been underestimated. Previous studies on the health and longevity of Americans primarily focused on white individuals. The research team emphasized, "This study shows a marked increase in dementia cases among black adults," adding that policies aimed at promoting healthy aging with an emphasis on equity are necessary. They also noted the need for more diverse studies that include Hispanic and Asian populations.
Some experts noted that the newly estimated figures could be overly high, but they agreed that the number of dementia patients will surge in the coming decades.
The aging process in the U.S. is advancing rapidly. According to the U.S. Census Bureau, by 2060, the population of the U.S. is expected to increase by 79 million to reach 440 million. However, by that time, it is projected that one in four Americans will be elderly. Dementia continues to impose a tremendous toll on American families and the national healthcare system.
Public health experts consider it essential to measure the risk of dementia in formulating public health strategies. This is because it allows time to prepare for dementia's onset based on age. Besides aging, genetic factors, high blood pressure, diabetes, obesity, an unhealthy diet, lack of exercise, and mental health also influence the onset of dementia.
Experts believe that simply changing lifestyle habits or managing chronic diseases can help lower the risk of dementia. For instance, wearing a helmet while cycling can also be a preventative measure against dementia. Repeated injuries due to collisions or falls can increase the likelihood of developing dementia in old age. Engaging in exercise from a young age and controlling blood pressure, diabetes, and cholesterol can also contribute to dementia prevention. High blood pressure and leukemia are linked to vascular dementia and Alzheimer's disease. In fact, recent years have seen a slight decrease in the incidence of dementia among patients with cardiovascular disease. This analysis indicates that the improved quality of treatment for cardiovascular diseases and higher educational levels have led to a reduction in dementia diagnoses.
Reference materials
Nature Medicine (2025), DOI: https://doi.org/10.1038/s41591-024-03340-9