What you need to know
The clusters of symptoms that patients with Long COVID develop tend to fit one of four categories or types, according to a study supported by the Researching COVID to Enhance Recovery (RECOVER) Initiative. Researchers found that the following diagnoses often occur together:
Type 1: Heart, kidney, and circulatory problems
Type 2: Lung conditions, sleep disorders, and anxiety
Type 3: Muscle pain, connective tissue disorders, and nervous system disorders
Type 4: Digestive and respiratory problems
What did the researchers do?
Researchers gathered the anonymous health records of more than 20,000 patients who previously had COVID-19. The researchers used a computer algorithm to find diagnoses that frequently appeared together in the patients’ health records a month or more after they tested positive for COVID-19 in 2020 or 2021. The researchers then repeated their analysis using a separate set of nearly 14,000 health records and confirmed their original results.
In addition to identifying the four Long COVID categories, the researchers discovered distinct characteristics about the patients in each group. For example, patients who developed Type 3 Long COVID were more likely to have had autoimmune diseases before getting COVID-19, and people who developed Type 1 Long COVID were more likely to have had severe COVID-19.
Why is this research important?
Patients and researchers have identified more than 200 symptoms of Long COVID, affecting nearly every part of the body. This makes it difficult to say exactly what Long COVID is. By defining what Long COVID can typically look like, these findings can help health care providers recognize when their patients have the condition and guide them to treatments to manage their symptoms. The findings can also help people find appropriate clinical trials for their specific Long COVID experiences.
For researchers, identifying common clusters of symptoms can help to understand what happens in the body after SARS-CoV-2 infection and why Long COVID develops. This research is an important example of the types of discoveries that are possible using data algorithms that analyze large volumes of health records.
Where can I go to learn more?
Learn what Long COVID is, how symptoms can present in different parts of the body, and what researchers now know about the condition.
This study was supported by the RECOVER Initiative. To help doctors and researchers better understand Long COVID, find a clinical study site near you.
The U.S. Department of Health and Human Services provides information on resources for people with symptoms of Long COVID that cause physical or mental impairment.
Zhang, H., Zang, C., Xu, Z., Zhang, Y., Xu, J., Bian, J., Morozyuk, D., Khullar, D., Zhang, Y., Nordvig, A. S., Schenck, E. J., Shenkman, E. A., Rothman, R. L., Block, J. P., Lyman, K., Weiner, M. G., Carton, T. W., Wang, F., & Kaushal, R. (2023). Data-driven identification of post-acute SARS-CoV-2 infection subphenotypes. Nature Medicine, 29, 226–235. https://doi.org/10.1038/s41591-022-02116-3
NIH COVID-19 Resources by Topic
COVID-19 research information and resources by topic from NIH institutes and centers