1 in 10 Americans over the age of 65 have dementia

About 1 in 10 adults over the age of 65 in the United States have dementia, and many more have mild cognitive impairment, the latest national estimates suggest.

According to Jennifer Manly, in a nationally representative cross-sectional study of approximately 3,500 older adults, 10% (95% CI 9-11) were classified as having dementia, and 22% (95% CI 20-11). 24) were classified as mild cognitive impairment. , Ph.D., Columbia University Irving Medical Center, New York City, and colleagues.

Dementia prevalence was similar by gender but varied by age, education, race, and ethnicity. Department of Neurology, JAMA.

The findings come from the first representative study of cognitive impairment in more than 20 years, researchers say. These are based on participants in the Harmonized Cognitive Assessment Protocol (HCAP) ongoing longitudinal health and retirement research project (time). HCAP is a cross-sectional random sample of his HRS participants in 2016 where he was 65 years or older.

“Because the HCAP study is part of a nationally representative long-term health and retirement study, these data not only show the current dementia burden, but also the trends in dementia burden over the coming decades. Co-author Kenneth Langa, M.D., Ph.D., of the University of Michigan, Ann Arbor, said in a statement:

“Given that COVID and other recent changes in population health may impact dementia risk in the decades to come, following these trends will be particularly important.” added Ranga.

Of 9,972 age-appropriate HRS participants, 3,496 were selected for HCAP and completed a comprehensive neuropsychological test and face-to-face interviews between June 2016 and October 2017 .

The researchers classified dementia and mild cognitive impairment using an algorithm based on standard diagnostic criteria and compared participants’ test performance with a control sample. They used population weights to estimate the national prevalence of dementia and mild cognitive impairment.

The average age of participants was 76.4 years and 60% were female. Overall, 71% self-identify as white, 16% black, 11% Hispanic, and 2% other races.

Dementia was more common in black participants (OR 1.81, 95% CI 1.20-2.75) and mild cognitive impairment was more common in Hispanic participants compared to white participants ( OR 1.42, 95% CI 1.03-1.96).

The rate increased sharply with age. From age 65 he had dementia in 3% of those aged 69, compared to 35% of those aged 90 and over. For every five years of age, the risk of dementia increased (OR 1.95 per 5-year age gap, 95% CI 1.77-2.14) and mild cognitive impairment (OR 1.17 per 5-year age gap, 95% CI 1.09). -1.26) ).

Each additional year of schooling was associated with a lower risk of dementia (OR 0.93, 95% CI 0.89-0.97) and mild cognitive impairment (OR 0.94, 95% CI 0.91-0.97).

The findings are similar to other recent estimates of dementia prevalence in the United States, Manly and colleagues say.

“Cognitive impairment will increase significantly in the coming decades as baby boomers live longer and older, impacting programs that provide care and services to individuals, families and people with dementia,” Manley said in a statement. is predicted to give

The study provides a snapshot in time and cannot assess the incidence or progression of cognitive impairment in people with mild cognitive impairment, the researchers noted. Studies have reported that the classification of mild cognitive impairment can fluctuate, with a high number of people returning to normal cognition at follow-up, they noted.

The cross-sectional design of the HCAP study “does not allow the investigation of survival biases. If some groups live longer with dementia, or if estimates of higher-mortality groups are declining.” , survival biases can inflate prevalence,” Manley and colleagues added.