A massive, new study has shown that older people who were infected with COVID-19 were at a substantially greater risk of developing Alzheimer's disease within a year.
A recent survey of more than 6 million people aged 65 and older suggests that older people who had a COVID-19 infection had a substantially higher risk of developing Alzheimer's disease within a year.
Researchers found that people 65 and older who had COVID-19 were significantly more likely to develop Alzheimer's disease in the year following their COVID diagnosis. Furthermore, the highest risk was found in women over the age of 85. The study was published on September 13, 2022, in the Journal of Alzheimer's Disease.
Following COVID infection, the risk of developing Alzheimer's disease in older people nearly doubled (0.35% to 0.68%) over a one-year period, according to the researchers. It is unclear whether COVID-19 initiates new development of Alzheimer's disease or accelerates its development.
Pamela Davis, the study's coauthor, believes that prior infections, especially viral infections, and inflammation, are overlooked. She is a Distinguished University Professor and The Arline H. and Curtis F. Garvin Research Professor at the Case Western Reserve School of Medicine.
"We wanted to investigate whether COVID might lead to increased diagnoses, even in the short term," said the study.
The research team examined 6.2 million people aged 65 and over in the United States who had received medical treatment between February 2020 and May 2021.
The other group consisted of people who had no documented COVID-19 cases, and the other group consisted of people who had no documented COVID-19 cases. More than 400,000 people were enrolled in the COVID study group, while 5.8 million were non-infected individuals.
“If the rise in new diagnoses of Alzheimer's disease is sustained, the increase in patients with a disease currently without a cure will be significant, and we may strain our long-term care budget,” Davis said. “We thought we had reversed some of the tide on it by reducing general risk factors such as hypertension, heart disease, obesity, and a sedentary lifestyle. Today, so many people in the United States have had COVID, and the long-term consequences of this disease are still emerging.
Rong Xu, the author of the study's corresponding author, is professor of biomedical informatics at the School of Medicine and the director of the Center for AI in Drug Discovery. She said the research team intends to continue studying the impacts of COVID-19 on Alzheimer's disease and other neurodegenerative disorders, including which subpopulations might be more vulnerable, as well as the potential to recycle FDA-approved medications to treat COVID's long-term effects.
Previous COVID-related research led by CWRU has revealed that people with dementia are twice as likely to contract COVID; those with substance abuse disorder orders are more likely to contract COVID; and that 5% of people who took Paxlovid for COVID symptoms developed rebound infections within a month.
Lindsey Wang, Pamela B. Davis, Nora D. Volkow, Nathan A. Berger, David C. Kaelber, and Rong Xu, the Journal of Alzheimer's Disease, will publish a paper on the 13th of September 2022. DOI: 10.3233/JAD-220717.