COVID-19 is associated with lupus flare and persistent disease activity: longitudinal data from the ReumaCov-Brazil Register study

Background: This study aimed to evaluate flares in systemic lupus erythematosus (SLE) patients over a period of six months after COVID-19. Methods: A multicenter, observational, and prospective cohort study was performed. SLE adult patients with COVID-19 (case group) were compared to SLE patients without COVID-19 (control group). Assessments were performed at baseline (V0), immediately after COVID-19 (V1), and three and six months after infection (V2 and V3). Disease activity was evaluated using the patient global assessment (PGA) and the modified SLE Disease Activity Index 2000 (mSLEDAI-2K). Flare was defined as an increase in the mSLEDAI-2K score of greater than three, and persistent disease activity was defined as mSLEDAI-2K score greater than three over two consecutive visits. Results: 715 patients were included, 363 in the case group and 352 in the control group. The case group had a higher mean age (SD) compared with the control group [41 years (12.38) versus 38.8 years (12.07), p=0.017]. The control group showed a significant reduction in PGA [0.24 (95% CI: -0.39 to -0.09), p=0.001] and SLEDAI-2K [0.85 (95% CI: 0.76 to 0.96) p=0.010] over the visits while in the case group the scores remained stable. The case group presented more frequent flares or persistent disease activity [74 (18.5%) versus 33 (10.5%), p=0.001]. COVID-19 at any time in the study was linked to a higher chance of a flare or persistent disease activity [OR=1.70 (95% CI: 1.06 to 2.74), p=0.029]. Conclusions: COVID-19 was associated with worse outcomes in SLE patients.