MONDAY, Oct. 24, 2022 (HealthDay News) — The national prevalence of dementia in 2016 was estimated at 10 percent, and that of mild cognitive impairment (MCI) was 22 percent, according to a study published online Oct. 24 in JAMA Neurology.
Jennifer J. Manly, Ph.D., from the Columbia University Irving Medical Center in New York City, and colleagues developed the Harmonized Cognitive Assessment Protocol to update national estimates of the prevalence of MCI and dementia in the United States. A total of 3,496 participants from the Health and Retirement Study, aged 65 years or older in 2016, completed a comprehensive neuropsychological test battery and informant interview.
The researchers found that 10 percent of the participants were classified as having dementia and 22 percent as having MCI. The risk for dementia and MCI was higher with each 5-year increase in age (weighted odds ratios, 1.95 and 1.17 per 5-year age difference). A decrease in the risk for dementia and MCI was seen for each additional year of education (odds ratios per year of school, 0.93 and 0.94, respectively). Compared with non-Hispanic Whites, dementia was more common in non-Hispanic Black individuals and MCI was more common in Hispanic individuals (odds ratios, 1.81 and 1.42, respectively). Due to small numbers, other group comparisons by race and ethnicity were not possible.
“These updated dementia prevalence estimates from 2016 show a disproportionate burden of dementia among older Black adults, of MCI among older Hispanic adults, and of both among people with lower educational attainment,” the authors write.