Post by Nadica (She/Her) on Aug 30, 2024 21:11:38 GMT
Does Long COVID Lead to Alzheimer’s? A New Study Took an Unexpected Turn - Published Aug 29, 2024
A study into whether long COVID patients were more prone to Alzheimer's instead opened the door to new treatments for long COVID itself.
Listen to the article via the link!
More than one in ten people who catch COVID don’t fully recover — developing a chronic condition called Long COVID which causes a variety of debilitating symptoms, including brain fog. Since some studies have found that COVID infections are associated with overall brain shrinkage, altered brain structure, and an increased risk of developing Alzheimer’s, researchers have been investigating the links between COVID and Alzheimer’s.
“There was a lot of discussion about whether COVID or even Long COVID would lead to a sudden onset form of Alzheimer’s disease so we set out to determine whether that was the case,” Dr. William Hu, director at the Center for Healthy Aging Research at Rutgers University told Being Patient.
Hu’s new study, published in Cell Reports Medicine, analyzed the cerebrospinal fluid and immune cells of Long COVID patients with brain fog. Rather than finding the telltale signs of Alzheimer’s, he discovered the patient’s immune system was still trying to fight off the COVID infection, which occurred about nine months prior. The patients whose immune cells mounted an antiviral response started to feel better — opening the door to new potential treatments for Long COVID that boost the body’s antiviral response.
What the study found
The researchers looked at a group of participants from COVID recovery clinics, comparing 100 without any cognitive complaints, 79 who had abnormal results on a cognitive assessment indicating cognitive impairment, and 57 who complained about cognitive issues even though they scored normally on a cognitive test.
Hu and his colleagues took cerebrospinal fluid and blood from both groups of people with cognitive complaints to measure protein biomarkers and look at what genes the immune cells are turning on or off to see whether there was an overlap with Alzheimer’s disease. “We did not find significant numbers of people with Alzheimer’s disease markers in the cerebrospinal fluid,” Hu said. “The many molecular pathways being active in Long COVID do not correspond to Alzheimer’s disease.”
But nine months after the initial infection, what the researchers did notice was that the immune cells behaved as if they were still fighting off a viral infection. About 50 percent of the cognitively impaired participants showed slow improvement after two years. The participants whose immune cells mounted an interferon response — a pathway used by the immune system to fight viruses — showed cognitive improvement.
“One of the key findings is that we see the immune cells in the cerebrospinal fluid, recruiting cells to fight infection,” Hu said. “So that tells me that the infection is in the brain.”
One limitation of the study is that it may not capture the experience of people with more severe Long COVID impairments — since Long COVID leads to extreme fatigue, some might not be able to participate in these studies.
Long COVID and Alzheimer’s
This study suggests that the mechanisms of Long COVID and Alzheimer’s disease are distinct. COVID-19 doesn’t seem to increase the levels of Alzheimer’s biomarkers.
“I think we can convincingly say right now that COVID does not cause acute Alzheimer’s disease,” Hu said. “Now whether it increases the risk for future Alzheimer’s disease is an open question.”
According to Hu, “there are many people walking around their 60s and 70s, with [asymptomatic] Alzheimer’s disease,” which means they have amyloid and tau in the brain but no symptoms. “A systemic illness [like COVID] can accelerate the manifestation of what previously was asymptomatic Alzheimer’s disease,” he said.
Although COVID-19 doesn’t directly cause Alzheimer’s disease, like other viral infections it may increase the risk of developing symptoms. This may explain why vaccines against the flu and other viral illnesses decrease the risk of developing Alzheimer’s disease.
Interferon and antiviral drugs for treating long COVID
There are currently no treatments available for Long COVID. While the National Institutes of Health has poured more than $1 billion into testing new treatments, the program has been criticized by scientific experts and patients as many of these studies are testing treatments like “exercise” and “cognitive behavioral therapy” which they say are ineffective and potentially harmful ((The National Institutes of Health’s Long COVID initiative RECOVER revised its exercise and exertion trials to reduce the risk of harm to participants.)
Hu said that patients should contact their elected representatives, senators, and congresspeople to ask them to accelerate new trials focused on developing antiviral therapies that might move the needle.
“Based on our data, it looks like a successful mounting of interferon-related pathways was associated with faster recovery,” he said. “Interferon itself can be tried and there are multiple forms of the drug.”
Interferon is already approved for treating multiple sclerosis, hepatitis C, non-Hodgkin’s lymphoma, and other autoimmune diseases. Interferon is also available in subcutaneous forms, which means that getting the drug wouldn’t require traveling to an infusion center for treatment.
How to prevent long COVID
COVID-19 vaccines may prevent severe illness and death, but Hu said that so far large studies suggest that vaccines do not prevent Long COVID in particular.
“What prevents Long COVID is not catching COVID,” said Hu. Experts suggest using multiple layers of protection to reduce the chances of catching COVID-19. “Two things that have consistently worked is good air ventilation, and masking,” Hu said. “They’ve consistently shown to be effective in preventing infection.”
High-quality surgical masks and respirators effectively reduce the transmission of airborne diseases like COVID-19 and can also protect your lungs and brain during wildfire season. Ensuring proper air ventilation by opening windows, using HEPA filters, and improving airflow with fans makes it harder for infectious particles or pollutants to linger in the air.
A study into whether long COVID patients were more prone to Alzheimer's instead opened the door to new treatments for long COVID itself.
Listen to the article via the link!
More than one in ten people who catch COVID don’t fully recover — developing a chronic condition called Long COVID which causes a variety of debilitating symptoms, including brain fog. Since some studies have found that COVID infections are associated with overall brain shrinkage, altered brain structure, and an increased risk of developing Alzheimer’s, researchers have been investigating the links between COVID and Alzheimer’s.
“There was a lot of discussion about whether COVID or even Long COVID would lead to a sudden onset form of Alzheimer’s disease so we set out to determine whether that was the case,” Dr. William Hu, director at the Center for Healthy Aging Research at Rutgers University told Being Patient.
Hu’s new study, published in Cell Reports Medicine, analyzed the cerebrospinal fluid and immune cells of Long COVID patients with brain fog. Rather than finding the telltale signs of Alzheimer’s, he discovered the patient’s immune system was still trying to fight off the COVID infection, which occurred about nine months prior. The patients whose immune cells mounted an antiviral response started to feel better — opening the door to new potential treatments for Long COVID that boost the body’s antiviral response.
What the study found
The researchers looked at a group of participants from COVID recovery clinics, comparing 100 without any cognitive complaints, 79 who had abnormal results on a cognitive assessment indicating cognitive impairment, and 57 who complained about cognitive issues even though they scored normally on a cognitive test.
Hu and his colleagues took cerebrospinal fluid and blood from both groups of people with cognitive complaints to measure protein biomarkers and look at what genes the immune cells are turning on or off to see whether there was an overlap with Alzheimer’s disease. “We did not find significant numbers of people with Alzheimer’s disease markers in the cerebrospinal fluid,” Hu said. “The many molecular pathways being active in Long COVID do not correspond to Alzheimer’s disease.”
But nine months after the initial infection, what the researchers did notice was that the immune cells behaved as if they were still fighting off a viral infection. About 50 percent of the cognitively impaired participants showed slow improvement after two years. The participants whose immune cells mounted an interferon response — a pathway used by the immune system to fight viruses — showed cognitive improvement.
“One of the key findings is that we see the immune cells in the cerebrospinal fluid, recruiting cells to fight infection,” Hu said. “So that tells me that the infection is in the brain.”
One limitation of the study is that it may not capture the experience of people with more severe Long COVID impairments — since Long COVID leads to extreme fatigue, some might not be able to participate in these studies.
Long COVID and Alzheimer’s
This study suggests that the mechanisms of Long COVID and Alzheimer’s disease are distinct. COVID-19 doesn’t seem to increase the levels of Alzheimer’s biomarkers.
“I think we can convincingly say right now that COVID does not cause acute Alzheimer’s disease,” Hu said. “Now whether it increases the risk for future Alzheimer’s disease is an open question.”
According to Hu, “there are many people walking around their 60s and 70s, with [asymptomatic] Alzheimer’s disease,” which means they have amyloid and tau in the brain but no symptoms. “A systemic illness [like COVID] can accelerate the manifestation of what previously was asymptomatic Alzheimer’s disease,” he said.
Although COVID-19 doesn’t directly cause Alzheimer’s disease, like other viral infections it may increase the risk of developing symptoms. This may explain why vaccines against the flu and other viral illnesses decrease the risk of developing Alzheimer’s disease.
Interferon and antiviral drugs for treating long COVID
There are currently no treatments available for Long COVID. While the National Institutes of Health has poured more than $1 billion into testing new treatments, the program has been criticized by scientific experts and patients as many of these studies are testing treatments like “exercise” and “cognitive behavioral therapy” which they say are ineffective and potentially harmful ((The National Institutes of Health’s Long COVID initiative RECOVER revised its exercise and exertion trials to reduce the risk of harm to participants.)
Hu said that patients should contact their elected representatives, senators, and congresspeople to ask them to accelerate new trials focused on developing antiviral therapies that might move the needle.
“Based on our data, it looks like a successful mounting of interferon-related pathways was associated with faster recovery,” he said. “Interferon itself can be tried and there are multiple forms of the drug.”
Interferon is already approved for treating multiple sclerosis, hepatitis C, non-Hodgkin’s lymphoma, and other autoimmune diseases. Interferon is also available in subcutaneous forms, which means that getting the drug wouldn’t require traveling to an infusion center for treatment.
How to prevent long COVID
COVID-19 vaccines may prevent severe illness and death, but Hu said that so far large studies suggest that vaccines do not prevent Long COVID in particular.
“What prevents Long COVID is not catching COVID,” said Hu. Experts suggest using multiple layers of protection to reduce the chances of catching COVID-19. “Two things that have consistently worked is good air ventilation, and masking,” Hu said. “They’ve consistently shown to be effective in preventing infection.”
High-quality surgical masks and respirators effectively reduce the transmission of airborne diseases like COVID-19 and can also protect your lungs and brain during wildfire season. Ensuring proper air ventilation by opening windows, using HEPA filters, and improving airflow with fans makes it harder for infectious particles or pollutants to linger in the air.