The frequency and outcome of lupus nephritis: results from an international inception cohort study

John G. Hanly, Aidan G. O’Keeffe, Li Su, Murray B. Urowitz, Juanita Romero-Diaz, Caroline Gordon, Sang-Cheol Bae, Sasha Bernatsky, Ann E. Clarke, Daniel J. Wallace, Joan T. Merrill, David A. Isenberg, Anisur Rahman, Ellen M. Ginzler, Paul Fortin, Dafna D. Gladman, Jorge Sanchez-Guerrero, Michelle Petri, Ian N. Bruce, Mary Anne Dooley, Rosalind Ramsey-Goldman, Cynthia Aranow, Graciela S. Alarcón, Barri J. Fessler, Kristjan Steinsson, Ola Nived, Gunnar K. Sturfelt, Susan Manzi, Munther A. Khamashta, Ronald F. van Vollenhoven, Asad A. Zoma, Manuel Ramos-Casals, Guillermo Ruiz-Irastorza, S. Sam Lim, Thomas Stoll, Murat Inanc, Kenneth C. Kalunian, Diane L. Kamen, Peter Maddison, Christine A. Peschken, Soren Jacobsen, Anca Askanase, Chris Theriault, Kara Thompson, Vernon Farewell

To determine nephritis outcomes in a prospective multi-ethnic/racial SLE inception cohort. Patients in the Systemic Lupus International Collaborating Clinics inception cohort (≤15 months of SLE diagnosis) were assessed annually for estimated glomerular filtration rate (eGFR), proteinuria and end-stage renal disease (ESRD). Health-related quality of life was measured by the Short Form (36 questions) health survey questionnaire (SF-36) subscales, mental and physical component summary scores. There were 1827 patients, 89% females, mean (s.d.) age 35.1 (13.3) years. The mean (s.d.) SLE duration at enrolment was 0.5 (0.3) years and follow-up 4.6 (3.4) years. LN occurred in 700 (38.3%) patients: 566/700 (80.9%) at enrolment and 134/700 (19.1%) during follow-up. Patients with nephritis were younger, more frequently men and of African, Asian and Hispanic race/ethnicity. The estimated overall 10-year incidence of ESRD was 4.3% (95% CI: 2.8%, 5.8%), and with nephritis was 10.1% (95% CI: 6.6%, 13.6%). Patients with nephritis had a higher risk of death (HR = 2.98, 95% CI: 1.48, 5.99; P = 0.002) and those with eGFR <30 ml/min at diagnosis had lower SF-36 physical component summary scores (P < 0.01) and lower Physical function, Physical role and Bodily pain scores. Over time, patients with abnormal eGFR and proteinuria had lower SF-36 mental component summary (P ≤ 0.02) scores compared to patients with normal values. LN occurred in 38.3% of SLE patients, frequently as the initial presentation, in a large multi-ethnic inception cohort. Despite current standard of care, nephritis was associated with ESRD and death, and renal insufficiency was linked to lower health-related quality of life. Further advances are required for the optimal treatment of LN.