Research Summaries

RECOVER researchers wanted to find environmental risk factors of Long COVID by comparing the environment of people who had Long COVID to people who didn’t have Long COVID. Environmental risk factors are things about where a person lives that raise their chance of having a health condition, such as air pollution and poor housing conditions. The researchers looked at data from electronic health records (EHRs) of more than 100,000 people in the New York City area and Florida.  

The researchers found that people who lived in areas with higher levels of air pollution, more poverty, and less access to healthy food had a higher chance of getting Long COVID. People in the New York City area had different environmental risk factors than people in Florida. 

RECOVER researchers analyzed electronic health records (EHR) in order to define Long COVID. Researchers found up to 25 different symptoms that patients who had COVID-19 were more likely to have than those who didn’t have COVID-19. The symptoms were related to many different organs, such as memory loss, hair loss, and feeling tired. They found that certain types of Long COVID symptoms were more likely to happen in patients who were older, had more severe COVID-19, or had more health problems before they had COVID-19. 

This research is important because the findings show that Long COVID affects many organs, and types of Long COVID symptoms differ between certain groups of patients. However, EHR findings are limited in that they can only look at data from the patients' past. In order to confirm these findings, future studies that follow patients' symptoms over time, into the future, are needed.

RECOVER researchers explored Multisystem Inflammatory Syndrome in Children (MIS-C), a Long COVID symptom where there is inflammation (swelling) of multiple organ systems. Researchers looked to see if MIS-C can be identified and managed in the home (outpatient) instead of in the hospital (inpatient). 

An organ system is a collection of organs in your body dedicated to maintaining necessary functions. For example, your heart, arteries, and veins make up the Cardiovascular System--the system responsible for maintaining blood flow and delivering oxygen throughout the body.

Researchers were able to identify that in some patients, their MIS-C symptoms were mild enough to be treated at home and not require hospitalization. These results raise awareness that MIS-C can present in milder forms with the option to treat it at home if directed by a physician.

RECOVER researchers reviewed ongoing, planned, and potential future treatment options for Long COVID, based on our current understanding of the biological causes of Long COVID symptoms and conditions. The purpose of this study is to help guide future research by summarizing the current state of the science as a call for urgent and efficient research to help the millions who continue to suffer from Long COVID around the world.

Researchers identified a number of studies that attempted to treat the various symptoms and conditions of Long COVID that may be useful to consider or incorporate when designing a larger research project aimed at treating the underlying biological cause of those symptoms and conditions.

RECOVER researchers conducted a detailed review of published papers that try to explain how the COVID-19 virus causes the symptoms and conditions associated with Long COVID. Researchers compared how Long COVID is similar to other long-standing viral conditions (such as Epstein Barr virus, commonly known as Mono) to see if there is a common method used by COVID-19 and these other viral conditions to cause the associated symptoms and conditions.

RECOVER researchers believe that there is no one common method by which the COVID-19 virus causes the symptoms and conditions associated with Long COVID. Because there was no observed common method causing these Long COVID symptoms, researchers recommend that treatments are customized to each individual patient's specific symptoms and conditions.

COVID-19 can damage the heart in ways that doctors are still working to understand. Some people develop heart problems during or after COVID-19 infection, including inflammation of the heart muscle. To better understand how the virus affects the heart, researchers studied heart tissue from people who died with COVID-19. They wanted to learn what happens to the blood vessels in the heart during infection. 

The research team examined heart tissue samples from autopsies using advanced techniques. These methods allowed them to see which genes were active in different parts of the tissue. They focused on cells that line the inside of blood vessels in the heart. The researchers compared tissue from 8 people who had COVID-19 to tissue from 4 people who died from other causes. They found that, in people with COVID-19, the blood vessel cells showed signs of stress and inflammation. These cells had turned on genes related to fighting infection and responding to injury. The team also found evidence of the virus itself in some heart tissue samples. 

These findings help explain why some people have heart problems after COVID-19. The virus appears to directly affect blood vessels in the heart, causing inflammation and damage. Understanding these changes at the cellular level may lead to new ways to prevent or treat heart problems in Long COVID.

Many people with COVID-19 experience brain-related symptoms like confusion, headaches, and difficulty thinking clearly. These problems can continue for months after infection as part of Long COVID. Scientists are working to understand why the virus affects the brain, even though it mainly attacks the lungs, heart, and intestines. 

Researchers studied how SARS-CoV-2 affects the cells that line tiny blood vessels in the brain. These cells form a protective barrier between blood and brain tissue. The team exposed human brain blood vessel cells and African monkey kidney blood vessel cells to live SARS-CoV-2 virus in laboratory experiments. They wanted to see how the virus infects cells and get through the protective barrier into brain tissue. The researchers measured how the cells responded by looking at inflammation markers, changes in the structure of the protective barriers, and changes in the cells’ energy-producing structures called mitochondria, which help maintain the protective brain barrier. 

The study found that exposure to SARS-CoV-2 triggered strong inflammation in brain blood vessel cells. The virus activated a specific inflammation pathway called NF-κB that isn't usually turned on in these cells. This led to increased production of inflammatory substances that could alter brain tissue. The researchers also discovered that the virus changed how mitochondria work in these cells. Mitochondria became longer and more connected to each other, which can happen when cells are under stress. These changes occurred even though the virus didn't directly infect or kill the brain blood vessel cells. 

These findings help explain how COVID-19 might cause brain symptoms without the virus directly infecting brain cells. The inflammation and changes in mitochondria could disrupt the cellular structure of the protective barrier between blood and brain. This disruption might allow harmful substances to enter brain tissue and cause thinking and memory problems seen in people with COVID. Understanding these mechanisms is an important step toward developing treatments for the neurological symptoms of COVID. 

The relationship between COVID-19 and diabetes has captured the interest of many researchers. Some studies suggest that people may be more likely to develop type 2 diabetes after having COVID-19. The authors of this study tried to find out whether new diagnoses of type 2 diabetes are more common after having COVID-19. They did this by looking at electronic health records (EHRs), which are digital medical charts that have health data like doctor visits, lab results, and other health history. 

The researchers looked at the EHRs of people across the country who had COVID-19 and were also diagnosed with type 2 diabetes within 6 months before or after having COVID-19. They found that the number of new diagnoses increased during the period when people had COVID-19, likely due to increased interaction with the healthcare system during that time. However, the average number of new diabetes diagnoses was about 83% lower in the 6 months after having COVID-19 than in the 6 months before having COVID-19. This analysis could not explain whether having COVID-19 makes people more likely to get diabetes, but it does include the unexpected finding that a diabetes diagnosis was less common months after having COVID-19.

RECOVER researchers looked at the use of a code to diagnose Long COVID in electronic health records (EHRs). They used EHR data from over 8,000 people and compared people who had the ICD-10 code for Long COVID (which is U09.9) in their EHR on or after October 1, 2021. They also looked at other codes in their EHR for health conditions, symptoms, tests, and treatments within 60 days after their Long COVID diagnosis.

Researchers found that many doctors use the Long COVID code along with other codes. People with Long COVID had a mix of symptoms and other health conditions, tests, and treatments. This suggests there may be different types of Long COVID. The researchers concluded that for now, doctors should look at a person’s mix of symptoms and other health conditions to diagnose Long COVID.