About a million Americans may develop some form of dementia each year by 2060, a to analyze was published on Monday Nature Medicine. The latest projections suggest a dramatic and dramatic increase from the projected annual cases by 2020, when approximately 514,000 adults in the US were estimated to be diagnosed with dementia, an umbrella term that describes a range of neurological conditions that affect memory and cognition.
The new study also showed that the risk of dementia gradually increased with age. After the age of 55, they calculated that the risk of dementia is 42%, and after the age of 85 it continues to rise to 56%. Groups showing higher lifetime risks (44% to 59% after age 55) were black adults, women, and carriers of the allele. APOE e4: that variation of the gene APOE, which encodes the apolipoprotein E protein, it increases the risk to develop Alzheimer’s disease. Alzheimer’s It is the most common cause of dementia, but the study focused on all forms.
“I knew the lifetime risk would be higher than the previous 20-year estimates,” he says. Joseph Koreshlead author of the study and founding director of the Institute for Optimal Aging at the NYU Grossman School of Medicine. “But I didn’t expect it to land at 42 percent.”
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Coresh’s team collected medical records from 15,043 people who signed up Atherosclerosis Risk in Community Study (ARIC)separate longitudinal study investigating the links between heart disease and cognitive health. The study cohort included adults aged 45 to 64 years who did not have dementia at the time of recruitment. About 31% of them were confirmed APOE e4 carriers.
Most medical experts define dementia as a collection of symptoms—such as life-threatening loss of memory, language, and other cognitive functions. degradation of brain cells. Coresh says a panel of medical experts evaluated participants’ symptoms and clinical data to diagnose dementia. Dementia studies often rely on medical and death records, as well as neuropsychological tests that measure a person’s mental state and detect signs of cognitive decline. Coresh explains that people may forget scheduled visits when their cognitive health declines, however. ARIC researchers conducted comprehensive risk assessments of each participant. And for those who missed in-person visits, they checked up annually or semi-annually by conducting phone interviews with those individuals or “informants,” such as relatives. The researchers confirmed dementia diagnoses in hospital or death records with informants whenever possible.
In the new study, the researchers reported on 3,252 cases of dementia and the probability of developing dementia by age 55 to 95 was 42 percent. Women’s lifetime risk was predicted to be higher after age 55, at 48 percent, compared to 35 percent for men. From the age of 55, adults with two copies APOE e4 had a higher lifetime risk (59%) than people with only one copy (48%). At that age, those without a copy of the allele had a 39 percent lifetime risk. The team then used projections from the US Census Bureau to estimate the annual number of dementia cases from 2020 to 2060.
According to Coresh, the growing population of elderly people in the US is the main driver behind the new study’s increase in dementia rates. “You can see how the slope (risk increases) with age, especially as the over-85 population grows dramatically,” he says. The current US life expectancy It is around 75 years for men and 80 for women, although recent studies suggest that from 2022 to 2050, life expectancy will increase globally. an increase of approximately five years.
Nancy McLinskeyThe neurologist at Stony Brook Medicine, who was not involved in the new study, says the results are not surprising, given the large number of older patients who come into his clinic seeking dementia care. “As the population lives longer, we will see a significant increase in cases,” he says.
The increase in dementia cases predicted in the study varied by race. Annual cases of dementia will dramatically double among white adults. And the cases among black adults are even more dire: their risk is expected to triple.
Black Americans often have it higher rates of heart diseasewhich some studies suggest may be a risk factor for dementia. Also, blacks live disproportionately medical racismoften leading to late diagnoses and lack of dementia treatment. McLinskey says the new report’s inclusion of more black participants compared to past studies could reflect a “potentially more accurate” picture of rising dementia rates.
Although the results of the study are in line with recent ones the modelsother data show different trajectories. 2024 Alzheimer’s Association report says that Alzheimer’s and other forms of dementia have actually declined in the US and other high-income countries over the past 25 years.
McLinskey says this decline may come from developing better treatments for dementia risk factors, such as high blood pressure and diabetes (both can increase the risk of damage to the blood vessels in the brain). Greater access continuing education for older adults it can also promote learning, which helps them cope with age- and disease-related brain changes.
Driven by the increase in life expectancy and a birth decline rates, the rapid growth of the country’s aging population could thwart current improvements, Coresh says. He emphasizes that people should take preventive measures now, even for those who are already over 55 years old. “The risk of dementia is high in older people,” he says, “but a large number can still be prevented with better vascular health.”
