Renal flares over time. The figure depicts the time to renal flare in distinct patient subgroups i.e. patients with low levels of C3 at baseline compared with patients with normal/high C3 levels (A), patients with positive anti-dsDNA antibody levels compared with patients who never tested positive for anti-dsDNA during follow-up (B), patients with positive anti-Sm antibody levels compared with patients who never tested positive for anti-Sm during follow-up (C), and patients with positive anti-ribosomal P protein antibody levels compared with patients who never tested positive for anti-ribosomal P protein autoantibodies during follow-up (D). Hazard ratios (HRs) and 95% CIs derive from univariable proportional hazards (Cox) regression analysis. C3: complement component 3; Sm: Smith