RECOVER Research Q&A: RECOVER “First Look” Adult Cohort Study
On May 25, 2023, RECOVER shared its “first look” into findings from the adult cohort study. The study, titled “Development of a Definition of Post-Acute Sequelae of SARS-CoV-2 Infection” was peer-reviewed and published in the Journal of the American Medical Association (JAMA). Read the full publication on the journal website.
The study and its findings have been shared among scientists, patients, caregivers, and community members around the world. As a result of this widespread interest, the below Q&A was developed to answer some of the most asked questions about this research and why it matters. View a summary of the JAMA study (PDF, 122 KB).
Please note: This study does not include children, and may not be representative of everyone with Long COVID.
What are the findings of this study?
- This study involved nearly 10,000 adults from the RECOVER adult cohort and examined 37 symptoms experienced by patients across multiple body areas and organs. Using these symptoms, researchers developed a scoring system to help find out which adults may have Long COVID. To do this, they compared people who were COVID-infected with people who were COVID-uninfected.
- The 12 symptoms that best differentiated (or set apart) people who were COVID-infected from those who were COVID-uninfected were included in the score. Each symptom was assigned a different number of points. People who had 12 or more points were considered likely to have Long COVID. Symptoms included: post exertional malaise, fatigue, brain fog, dizziness, gastrointestinal symptoms, heart palpitations, issues with sexual desire or capacity, change in smell or taste, thirst, chronic cough, chest pain, and abnormal movements.
- The use of 12 symptoms for the score in no way minimizes the importance of the many other symptoms people experience, and does not make any of them less real, debilitating, common, important, or worthy of scientific research and medical attention.
- Researchers also found that Long COVID (as measured by this study’s scoring system) was more common in participants infected in the pre-Omicron era as well as in those who were unvaccinated at the time of infection. Additionally, reinfections were linked to higher Long COVID frequency and severity.
Why is this study important?
- This study and its scoring system are important because currently, there is no definition of Long COVID that researchers can use to identify the disease. Researchers will continue working to improve the study’s scoring system as more data are gathered to better understand Long COVID, including its causes and potential treatments.
Should insurers, disability agencies, or doctors use these study findings to clinically define Long COVID, and what is meant by “working definition”?
- No. Insurers, disability agencies, and/or doctors should not use findings from this study to clinically define or rule out Long COVID.
- RECOVER research to date has been focused on better characterizing and understanding the disease. As we learn more about it, a “working definition”—or a definition being developed—evolves. As further research is conducted, the definition is improved. More work is needed before this definition can be used in clinical practice.
- One of the core findings of this study is that it refines the working definition of Long COVID. This means that the study does not offer a clinical definition, which would require review, approval, and wide acceptance by clinicians. As a next step, researchers will explore adding information from lab tests and imaging to the definition.
Why are some common Long COVID symptoms not in the score?
- The symptoms in the score are not necessarily the most common symptoms experienced by patients. Some of the more common symptoms reported by infected participants, such as weakness, headache, dry mouth, sleep disturbance or muscle pain, are not included in the scoring system because they are also common in people who do not have Long COVID. By contrast, some of the symptoms in the score occur rarely even in people with Long COVID. However, it is important to note that people who had the symptoms in the scoring system also had many other symptoms.
Can people who don’t have 12 or more points in the scoring system still have Long COVID?
- Yes. Some people who have Long COVID may not meet the scoring threshold outlined in this study.
Can people who don’t have all 12 symptoms still have Long COVID?
- Yes. People can meet the threshold of 12 points without having every symptom.
Does the symptom score include severity of symptoms?
- Yes, for symptoms with validated severity scores available, symptoms are included if they are at least moderate in severity. However, the range of symptom severity does not play into the scoring system. For example, having a severe symptom does not provide a higher score than having a moderate symptom. This will be an important aspect to consider in future research and refinements.
Will the scoring system outlined in this study be used as criteria for entry into RECOVER clinical trials?
- RECOVER clinical trial protocols are currently in development and not final. At this time, the scoring system outlined in this study is not being used as a criterion for entry.
What about those whose Long COVID symptoms are not captured in this study?
- More than 200 symptoms affecting the body and all its systems have been associated with Long COVID, and more symptoms and conditions may be identified as research continues. This study considered 37 symptoms, and identified 12 that were most distinguishable when comparing COVID-infected and COVID-uninfected groups.
- Again, this study’s consideration of certain symptoms does not make other symptoms less real, debilitating, common, important, or worthy of scientific research and medical attention.
Is this the first study coming out of the RECOVER Initiative?
- This is the first study reporting results from the RECOVER adult cohort.
- However, this study is one of many RECOVER publications that contribute to our growing knowledge of the risk factors for and potential causes of Long COVID. View the most recent RECOVER publications on our website. Dozens of other publications are in progress, including some analyzing risk factors for Long COVID, such as reinfection and vaccination status. RECOVER researchers are also exploring how COVID infection affects children and adolescents—who are widely understudied—and people who were pregnant while having COVID.