Older adults are at a 69 per cent higher risk of developing Alzheimer’s disease within a year of infection with Covid, a new study has found.
The findings, published in the Journal of Alzheimer’s Disease (JAD), were based on data from more than six million Americans over the age of 65 who had no previous diagnosis of Alzheimer’s disease.
The study involved analysis of the medical records from February 2020 to May 2021. It found that a total of 410,748 participants tested positive for COVID-19 during the study period, while 5.8 million did not.
Those previously infected with the virus had a 69 per cent higher risk of a new diagnosis of Alzheimer’s disease within a year of infection than their uninfected peers, with those over the age of 85 years at particularly higher risk.
“Our findings call for research to understand the underlying mechanisms and for continuous surveillance of long-term impacts of COVID-19 on Alzheimer’s disease,” the authors explained.
While it is not clear whether Covid could trigger or accelerate the development of Alzheimer’s disease, the researchers noted that SARS-CoV-2 has been associated with inflammation and central nervous system disorders.
“The factors that play into the development of Alzheimer’s disease have been poorly understood, but two pieces considered important are prior infections, especially viral infections, and inflammation,” co-author Pamela Davis, MD, PhD, said.
Any increase in new-onset Alzheimer’s disease translates to a higher number of older patients with an incurable disease could be substantial and may further strain care resources already under pressure, Davis added.
“We thought we had turned some of the tide on it by reducing general risk factors such as hypertension, heart disease, obesity and a sedentary lifestyle.
“Now, so many people in the US have had Covid and the long-term consequences of Covid are still emerging. It is important to continue to monitor the impact of this disease on future disability,” she explained.
The researchers will continue studying the potential effects of the virus on Alzheimer’s and other neurodegenerative diseases as well as its impact on certain age groups.
