Introduction: Multiple cases of autoimmune rheumatic diseases following COVID-19 have been reported in the literature. This study aims to systematically determine whether COVID-19 affects the incidence of autoimmune rheumatic diseases. Methods: We searched MEDLINE (PubMed), Global Index Medicus, and Cochrane Library da-tabases up to March 30, 2024, for studies evaluating the incidence of systemic autoimmune dis-eases following SARS-CoV-2 infection in adult populations. Results: Eight cohort studies with 5,537,742 COVID-19 and 18,433,129 non-COVID-19 patients were included in our pooled analysis. The risk of developing mixed connective tissue disease and Behçet’s disease in COVID-19 patients was increased by 168% (RR: 2.68, 95% CI (1.14 to 6.34), I²=94%) and 101% (RR: 2.01, 95% CI (1.4 to 2.87), I²=6%), respectively, compared to uninfected subjects. A 45% increase in the risk of both rheumatoid arthritis (RR: 1.45, 95% CI (1.02 to 2.06), I²=99%) and psoriasis (RR: 1.45, 95% CI (1.10 to 1.92), I²=98%) after SARS-CoV-2 infection was noted. The risk of dermatopolymyositis was 40% higher (RR: 1.40, 95% CI (1.10 to 1.79), I²=68%) in the COVID-19 group. Non-significant increases in risk were observed in the pooled analysis for ankylosing spondylitis (RR: 1.39, 95% CI (0.94 to 2.05), I²=93%), systemic lupus er-ythematosus (RR: 1.21, 95% CI (0.70 to 2.07), I²=98%), systemic sclerosis (RR: 1.23, 95% CI (0.73 to 2.04), I²=89%), Sjögren’s syndrome (RR: 1.28, 95% CI (0.91 to 1.80), I²=95%), and pol-ymyalgia rheumatica (RR: 1.45, 95% CI (0.94 to 2.25), I²=94%). Discussion: Since the onset of COVID-19, several cases of new-onset autoimmune rheumatic diseases following SARS-CoV-2 infection have been reported. To the best of our knowledge, this is the first systematic review and meta-analysis assessing the impact of COVID-19 on the risk of developing autoimmune rheumatic diseases. Overall, COVID-19 increases the risk of autoim-mune rheumatic diseases, especially during the first year after infection. Conclusion: COVID-19 is associated with an increased risk of several autoimmune rheumatic diseases, including mixed connective tissue disease, Behçet’s disease, rheumatoid arthritis, psori-asis, and dermatopolymyositis. However, our results must be interpreted with caution due to high inter-study heterogeneity. Registration: PROSPERO CRD42023480593
Agouridis et al. (Thu,) studied this question.