People who suffer loss of smell during COVID-19 illness may be at higher risk of dementia-related brain changes, researchers say.

A bout with COVID-19 can cause dementia-like brain changes and related functional decline, according to studies being presented at this week’s Alzheimer’s Association International Conference.

Researchers worldwide are finding that people who recover from severe disease may be especially at risk of persistent functional difficulties seen in Alzheimer’s disease, according to a new report from National Public Radio.

One study, the results of which the lead author called “downright scary,” found that Alzheimer’s diagnoses were more common in older adults who had survived severe COVID-19.  

Problems with smell tied to brain changes

What’s more, people who suffer loss of smell due to the disease appear to be most at risk of dementia-related brain changes, the same research team told NPR. This may be because the olfactory bulb, which facilitates smell, is near brain areas tied to memory, planning and mood. These areas may be damaged together, the investigators said.

Another study has found that brain scans taken before and after COVID-19 illness reveal changes similar to those of Alzheimer’s. Yet others have found that functional loss of memory and language abilities, such as forgetting names and phone numbers, can last for months after recovery. Some researchers refer to these long-term changes as an Alzheimer’s-like syndrome, NPR reported.

The key question now is how long these changes may last and how permanent they may be, investigators said. It may take at least a decade to see how the millions of former COVID-19 patients with ongoing cognitive or mood problems will fare, Sudha Seshadri, M.D., an Alzheimer’s expert at UT Health San Antonio, told the news outlet.

“Even if the effect is small, it’s something we’re going to have to factor in because the population [of recovered COVID-19 patients] is quite large,” she said.

Meanwhile, recovering patients are attempting to soldier forward as best they can, NPR reported. 

“We were at dinner and I forgot how to use a fork,” one nurse and former COVID-19 patient told the news outlet. “It was embarrassing.”