About 15 million Americans will have Alzheimer's dementia or mild cognitive impairment by 2060, compared to about 6.08 million this year, according to a new study by researchers at UCLA's Fielding School of Public Health.
The findings highlight the need to develop measures that can slow the progression of the disease in people who have evidence of neuropathological changes that could eventually lead to Alzheimer's dementia, said Ron Brookmeyer, professor of biostatistics at the School of Public Health from UCLA Fielding and lead author of the study. The population of the country is getting older and with it comes a growing number of people with Alzheimer's disease.
The study was published today in the peer-reviewed journal Alzheimer's and Dementia: The Journal of the Alzheimer's Association. The study is the first of its kind to estimate the number of Americans with preclinical Alzheimer's disease or mild cognitive impairment.
"Today in the United States there are some 47 million people who have some evidence of preclinical Alzheimer's, which means they have either an accumulation of protein fragments called beta-amyloid or neurodegeneration of the brain, but still have no symptoms" said Brookmeyer. "Many of them will not progress to Alzheimer's dementia in their lives, we need to have improved methods to identify which people will progress to clinical symptoms, and develop interventions for them that could slow the progression of the disease, if not stop all together."
The researchers examined the largest studies available on the rates of progression of Alzheimer's disease and used that information in a computer model they built that took into account the aging population of EE. UU The model projected the number of people in preclinical and clinical disease states.
They found that by 2060, approximately 5.7 million Americans will have mild cognitive impairment and another 9.3 million will have dementia due to Alzheimer's disease. Of this last group, around 4 million Americans will need an intensive level of care similar to that provided by nursing homes. Mild cognitive impairment is an intermediate clinical stage that still does not meet the threshold for dementia. Brookmeyer estimates that currently about 2.4 million Americans live with mild cognitive impairment due to Alzheimer's disease.
"Estimates by disease status and severity are important because the resources needed to care for patients vary so much in the course of the disease," Brookmeyer said.
There are some sources of uncertainty in the findings. Participants in studies examined by researchers may not represent all demographic data. In addition, there are other types of dementia, such as vascular dementia, that were not examined, but could have an impact on these numbers.
The co-authors of the study are Nada Abdalla, Ph.D. student in biostatistics from Fielding School and Dr. Claudia Kawas and Maria Corrada from UC Irvine.
The National Institutes of Health funded this study.