People with dementia more likely to catch and die from COVID, study finds. Why?

An analysis of more than 61.9 million patient records in the U.S. found that people with dementia are more than three times as likely to get infected with the coronavirus than individuals without dementia.

Even after researchers adjusted for COVID-19 risk factors that may have led to worse disease outcomes in patients with dementia, such as cardiovascular disease, diabetes, obesity and asthma — factors that also pose risks for dementia itself — those with dementia are still twice as likely to contract the coronavirus.

This, researchers say, suggests there’s something about dementia, an umbrella term for a group of conditions that affect the brain, that puts the estimated 5.8 million Americans living with it in greater danger of infection.

The group also faces increased risks of COVID-19 hospitalization and death.

“These findings highlight the need to protect patients with dementia as part of the strategy to control the COVID‐19 pandemic,” the researchers wrote in the study published Tuesday in the journal Alzheimer’s & Dementia.

And consistent with existing data on COVID-19 racial disparities, Black people with dementia are nearly three times more likely to be infected with the coronavirus than white people with dementia, after adjusting for age, sex and COVID‐19 risk factors.

Black individuals with dementia were also more likely to be hospitalized with the disease, but not significantly more likely to die from it than white people with dementia. Take COVID-19 risk factors out of the picture, and Black Americans with dementia still faced similar risks compared to their white counterparts.

“Our study showed similar racial disparity for COVID‐19 risk before and after controlling for COVID‐19 risk factors, suggesting that factors other than strictly medical conditions, including access to health care, socioeconomic status, and social adversity, may have contributed to this profound racial disparity,” the researchers wrote.

Data from 360 hospitals and 317,000 providers across 50 states, “representing 20% of the U.S. population” were collected by the IBM Watson Health Explorys. The study comprised more than 61.9 million adult patient records since the pandemic began in March 2020 up to Aug. 21, including 15,770 patients who had COVID-19, 810 of which had both dementia and COVID-19.

Why do patients with dementia face greater COVID-19 risks?

The researchers speculate that dementia-specific characteristics may be playing just as large a role in increasing this populations’ odds of infection than some COVID-19 risk factors themselves, such as obesity and heart disease.

For example, people with dementia have damaged blood-brain barriers, meaning certain bacteria and viruses are able to access the brain more easily, making people with dementia more susceptible to infections of any kind.

Dementia, which includes Alzheimer’s disease, also affects memory. Experts say this may interfere with people’s ability to abide by coronavirus preventive measures, which could raise their chances of getting sick.

“Folks with dementia are more dependent on those around them to do the safety stuff, to remember to wear a mask, to keep people away through social distancing,” Dr. Kenneth Langa, a professor of medicine at the University of Michigan, who was not involved in the study, told The New York Times. “There is the cognitive impairment and the fact that they are more socially at risk.”

Because there was limited data on these lifestyle factors, the researchers say they cannot say for certain how these factors contributed to increased risks for COVID-19 in people with dementia.

Still, such factors could answer why the odds of COVID-19 in patients with dementia were still so high after adjusting for COVID-19 risk factors.

Age, sex didn’t increase risks of coronavirus infection

Data show that men and older individuals face higher COVID-19 risks than women and younger people. But these differences were “less obvious” in patients with dementia, the researchers found.

Despite having weaker body systems and functions compared to younger individuals, older people, as well as older patients with dementia, may be more likely to stay home and less likely to work or socialize. This, the team said, lowers potential exposure to the coronavirus and may explain why age had no additional effect on getting COVID-19 among people with dementia.