AimSince the coronavirus outbreak became a global health emergency in 2020, various immune-based effects, such as inflammatory arthritis (IA), have been recorded. This study aimed to determine the role of COVID-19 severity on post-COVID arthritis.MethodsWe systematically reviewed 95 patients who developed arthritis after severe and non-severe COVID-19 infection by searching the databases, including PubMed, SCOPUS, and EMBASE. We used the term "COVID-associated arthritis" because there was no definite diagnostic method for classifying arthritides after COVID-19 infection, and the diagnosed arthritis types were based on the authors' viewpoints.ResultsAfter evaluating the data between the two severe and non-severe COVID-19-infected groups of patients, the results showed that the COVID-19 severity may affect the pattern of joint involvement in IA. In both groups, combination therapy, including oral nonsteroidal anti-inflammatory drugs with different types of corticosteroids, was the most common treatment. In addition, the mean age and comorbidities rate was higher in the severe COVID-19 group. Even though the patients in the severe COVID-19 group developed more serious COVID-19 symptoms, they experienced milder arthritis with better outcomes and more delayed onsets that required less aggressive therapy.ConclusionWe conclude that there may be an inverse relationship between COVID-19 severity and arthritis severity, possibly due to weaker immunity conditions following immunosuppressant treatments in patients with severe COVID-19. This study compares COVID-associated arthritis in two non-severe COVID-19 and severe COVID-19 categories by collecting data from 95 cases. We conclude that the prevalence of COVID-associated arthritis may increase with COVID-19 severity. However, there is an inverse relationship between COVID-19 severity and arthritis severity, probably because of weaker immunity conditions following immunosuppressant therapy in patients with severe COVID-19.image