COVID-19 survivors who have long-term memory problems are at higher risk for Alzheimer’s

Scientists looking at patients with long-term COVID-19 symptoms are concerned that they could later develop Alzheimer’s disease.

Researchers from UT Health San Antonio have followed Covid patients with long-term neurological symptoms for the past year, and are presenting their findings this week at the Alzheimer’s Association International Conference.

The team found younger patients are likely to suffer from Covid-induced anxiety and depression, while patients in their 60s and 70s have symptoms similar to early-onset Alzheimer’s.

Even if a small number of Covid patients is impacted by long-term neurological issues, it could be devastating for the U.S. healthcare system.

Covid patients with long-term neurological symptoms are at high risk of developing Alzheimer’s later in life, new research suggests. Pictured: A staff member at a retirement home in France speaks with a resident in April 2020

Dr de Erausquin, lead researcher on the study, describes his findings in an April 2021 talk

Dr de Erausquin, lead researcher on the study, describes his findings in an April 2021 talk

While most people infected with the coronavirus have mild or no symptoms, a small number suffer for months – and could be impacted for years after they recover.

Common symptoms among these long-hauler patients are brain fog, memory problems, and fatigue, along with other neurological issues.

According to one study, up to a third of Covid patients show these symptoms – even after they appear to have recovered from the virus.

Scientists are now concerned that these long-term neurological symptoms could lead to worse conditions later in life.

New research from the University of Texas (UT) Health Science Center in San Antonio indicates that long Covid patients with neurological issues are at risk of Alzheimer’s.

The researchers followed Covid patients with these symptoms for about a year, with the study including more than 50 centers across 30 countries.

This week, the researchers are presenting preliminary findings at the Alzheimer’s Association International Conference, which started Monday in Denver, Colorado.

For Cassandra Hernandez, a nurse at a hospital in San Antonio, Texas, who matches the study’s patient profile, the initial sign of Covid was a loss of taste and smell.

‘I went home after working a 12-hour shift and sat down to eat a pint of ice cream with my husband and I couldn’t taste it,’ she told NPR.

After two weeks in the hospital and months at home disabled with fatigue, memory issues, and other symptoms, Hernandez has had a long road to recovery.

‘I would literally fall asleep if I was having a conversation or doing anything that involved my brain,’ she said.

Hernandez may now be at risk of Alzheimer’s, according to the UT Health San Antonio group’s research.

Covid patients in their 60s and 70s had symptoms similar to early-onset Alzheimer's, the researchers found. Pictured: Nurses measure the blood pressure of a nursing home patient in Belgium, July 2020

Covid patients in their 60s and 70s had symptoms similar to early-onset Alzheimer’s, the researchers found. Pictured: Nurses measure the blood pressure of a nursing home patient in Belgium, July 2020

The researchers found that loss of smell may be an early indicator of this risk, because the parts of the brain involved in smell are also connected to memory, thinking, planning, and mood.

‘Persistent lack of smell, it’s associated with brain changes not just in the olfactory bulb but those places that are connected one way or another to the smell sense,’ Dr Gabriel de Erausquin, neurology professor at UT Health San Antonio and lead author on the study, told NPR.

Younger patients – such as those in their 30s – are more likely to develop anxiety and depression, the researchers found.

Older patients, on the other hand, were likely to develop symptoms similar to early Alzheimer’s. And these symptoms can go on for months.

‘In older people, people over 60, the foremost manifestation is forgetfulness,’ de Erausquin said.

‘These folks tend to forget where they placed things, they tend to forget names, they tend to forget phone numbers. They also have trouble with language; they begin forgetting words.’

Such findings align with results from brain scans showing that Covid infection can cause changes similar to those seen in Alzheimer’s patients.

Genetic studies have also shown overlap between the genes that increase severe Covid risk – and the genes that increase Alzheimer’s risk.

De Erausquin said these patients ‘look really bad right now,’ but it is difficult to predict how their symptoms may progress in coming years.

For younger patients in particular, it could be decades before the full impacts of Covid are revealed.

Even if the number of patients with such long-term, debilitating symptoms is small compared to the millions of Americans infected with Covid, the impact on the national healthcare system could be immense.

Already, more than six million Americans are living with Alzheimer’s. 

The age-related brain disease is a leading cause of death for seniors, and treatments are limited – or very expensive, in the case of the controversial newly-approved Aduhelm.

President Joe Biden recently announced that patients with long Covid symptoms are now eligible for disability benefits in the U.S.

The decision could potentially add millions to the disability system, with some patients suffering Covid impacts for years to come.

Meanwhile, scientists are looking to better understand how Covid interacts with the brain, keeping an eye on other viruses that can cause long-term neurological issues.

‘If one understands how the immune response to this virus is accelerating [Alzheimer’s] disease, we may learn about the impact of other viruses,’ Dr Sudha Seshadri, another Alzheimer’s researcher at UT Health San Antonio, told NPR.