The risk of older people (over 65) developing Alzheimer’s disease over a one-year period nearly doubled following a COVID-19 diagnosis. The same researchers had previously found that individuals with dementia had a greater risk of contracting COVID-19 and being hospitalized and dying from the disease than those without dementia.
“Many people believe that for Alzheimer’s disease there is a combination of factors that work together to give you the cognitive impairment, and we were concerned that the kinds of things that happened during COVID-19 — the intense inflammation, and perhaps the kinds of direct action on the brain of the of the virus — might be a risk factor,” Dr. Davis, the study’s co-author, said. “So we went looking for that in our study.”
“We can say that they are associated, but we cannot infer causality,” she stressed.
“First, the pandemic presented serious delays for individuals seeking out medical diagnoses like Alzheimer’s disease, meaning these results could be driven by those who already had Alzheimer’s disease when they were infected but had not yet sought out a formal diagnosis,” Dr. Snyder, vice president of medical and scientific relations at the Alzheimer’s Association, explained.
“Alternatively, COVID-19 infection — which is linked to immune changes, including inflammation — may impact the onset of brain changes that are linked to Alzheimer’s disease and other dementia,” said Dr. Snyder. “However, because this study only showed an association through medical records, we cannot know what the underlying mechanisms driving this association are without more research.”
Association of COVID-19 with New-Onset Alzheimer’s Disease