P88 Baseline factors associated with subsequent development of incident nephritis in patients with systemic lupus erythematosus: a retrospective cohort study

Objective To discern predictive factors for the development of incident lupus nephritis (LN) in systemic lupus erythematosus (SLE) patients. Methods Patients with SLE, according to American College of Rheumatology 1997 criteria and/or the Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) 2012 criteria, from a mixed prevalent and incident cohort ('Attikon' Lupus cohort) were followed for development of biopsy-proven nephritis. Demographics, clinical characteristics and laboratory values at baseline were compared against patients who did not develop LN. LN-free survival curves were generated using the Kaplan-Meier method and a multivariate Cox proportional hazards model was used to identify independent predictors of LN, after adjusting for potential confounders. Results Of 570 patients, 59 manifested LN as presenting clinical manifestation and 66 developed LN during follow-up (total 21.9% of the entire cohort). On univariate analysis, male sex, younger age at disease onset, low C3 and/or C4 and high anti-dsDNA titre at baseline were associated with a higher risk of LN. On multivariate analysis, baseline factors predictive of future nephritis were male sex (aHR 3.79, 95% CI: 1.61–8.91, p Conclusions Male sex, younger age and -especially combined- serologic activity at the time of SLE diagnosis are strongly associated with LN development. Vigilant surveillance for early signs of nephritis is particularly warranted in these subsets of patients.