Exploring Ties Between COVID and Alzheimer’s Disease
The COVID symptom known as “brain fog” can be frustrating and disruptive to daily life.
The good news: post-COVID brain fog isn’t permanent.
However, there’s reason to think COVID-19 may cause blood vessel changes related to brain disease. Neurologists and infectious disease experts are studying the potential connection.
Brain fog can include thinking and processing information at a slower speed, trouble finding the right words, forgetfulness, mental confusion, feeling in “a daze,” and memory issues. Experiencing this sudden lack of mental clarity may feel like early-onset dementia or Alzheimer’s, but they are not the same conditions.
Can COVID-19 trigger dementia?
“I have participated in two expert forums to discuss the current state of knowledge regarding COVID-19 infection and dementia,” says James E. Galvin, M.D., M.P.H., a neurologist with the University of Miami Health System and director of UM’s Comprehensive Center for Brain Health. “To date, there is no clear link between the two.”
But, there’s evidence that COVID-19 infection can affect blood vessels and increase inflammation.
“It is possible these vascular changes and inflammation could potentially have long-term, downstream effects on brain health and lead to a higher risk of dementia. It is too early to know.”
Ongoing research on this topic will help us better understand the relationship between coronavirus infection and chronic diseases that affect the brain. Dr. Galvin and his team recently received a National Institutes of Health grant to explore the unique risks for COVID and brain health faced by certain populations.
How are race and ethnicity related to COVID and brain health?
“Compared with non-Hispanic white individuals, African Americans are at a two-fold increased risk of Alzheimer’s disease. Hispanics are at a 1.5-fold increased risk, and Native Americans are at a two- to three-fold increased risk. Rural populations have a 1.2-fold increased risk,” says Dr. Galvin.
Similarly, these communities face an increased risk of COVID-19 infection, severe disease, and death.
“The coronavirus pandemic laid bare the stark racial disparities in the United States,” he says.
“COVID-19 infections in African Americans are more severe. Blacks are about 4.6 times more likely to be hospitalized than whites.
“In Florida, this is further exaggerated with 3.1 times increased mortality from COVID disease. African Americans also have a higher risk of chronic obstructive pulmonary disease (COPD), which is a risk factor for COVID-19 and its complications.”
New, early research shows that reduced lung function can make people vulnerable to cognitive issues, dementia, and neurodegeneration (found in patients with Alzheimer’s disease). Impaired lung function can potentially lead to vascular changes that affect the brain’s ability to communicate with muscles and organs.
What may be an underlying cause? Air pollution.
“Air pollution is likely a critical environmental factor that increases COVID-19 susceptibility. A recent report suggests that long-term exposure to particulate matter in the air can lead to increased COVID-19 death rates,” Dr. Galvin says.
He is focusing his research on Florida’s rural region, called The Glades.
The area surrounds Lake Okeechobee and has been particularly devastated by COVID-19. In this community, sugarcane farming is the predominant industry. This farming involves burning fields to harvest crops, releasing particulate matter into the air. Dr. Galvin says that farmworkers and those living in the surrounding communities are exposed to 15 times the average volume of these dangerous atmospheric aerosol particles during the harvest season.
“We will look at whether the combination of environmental exposures, genetics, and vascular risk factors contribute both to the increased risk and worse health outcomes,” he says. “Our hypothesis is that chronic exposure to particulate matter increases the risk of COPD. That in turn, increases the risk of COVID-19; dementia; and COVID-associated consequences on dementia risk, progression, and outcomes.”
Risk levels for COVID-19, lung function disorders, and brain disease are related to lifestyle, genetic, and cultural factors. These include inherent racial and ethnic differences and access to health care based on:
- geographic location and socioeconomic status
- discrimination and inequities in the health care system
- higher rates of obesity, diabetes, and hypertension among racial and ethnic minorities
Research on this topic by Dr. Galvin and other leading health experts sheds light on complex health disparities and outcomes across the country.
Dana Kantrowitz is a contributor to UHealth’s news service.