Long-term outcome and prognostic indicators of diffuse proliferative lupus nephritis

Abstract

Objective To investigate the long-term outcome and prognostic indicators of diffuse pro-liferative lupus nephritis (DPLN). Methods The primary endpoint of long-term follow-up and factors pos- sibly influencing the outcome were analyzed retrospectively in DPLN patients admitted to the First Affiliated Hospital of Wenzhou Medical University between Jan 1, 2000 and Dec 31, 2014. Patients were classified into three groups according to the evaluated glomerular filtration rate(eGFR) on the first day of admission: eGFR≥60 ml·min-1·1.73 m-2 (regular illness group); 15 ml·min-1·1.73 m-2≤eGFR<60 ml·min-1·1.73 m-2 (serious illness group); eGFR<15 ml·min-1·1.73 m-2 or dialysis (critical illness group). Clinical, histological, and outcome differences among the three groups were evaluated and compared using one-way analysis of variance (ANOVA) , χ2 test, Kaplan-Meier survival curve and Cox reggression analysis. Results 167 DPLN patients were studied [155 women; mean age (30±10) years; mean follow-up of (61±45) months]. Renal and patient survival of all patients was 86% at 5 years and 79% at 10 years. Kaplan-Meier analysis showed the renal and patient survival rate at 10 years in the regular illness group, serious illness group and critical illness group was 91%, 70% and 8%, respectively (χ2=121.93, P<0.01, overall); regular illness group vs serious illness group (χ2=4.05, P<0.05); regular illness group vs critical illness group (χ2=97.05, P<0.01); serious illness group vs critical illness group (χ2=52.28, P<0.01). Multivariable Cox regression analysis found that haematoglobin (Hb)<80 g/L [HR=2.7, 95%CI(1.2, 6.3), P=0.019], eGFR<60 ml·min-1·1.73 m-2 [HR=4.1, 95%CI(2.0, 8.2), P<0.01] and large crescents ≥30%[HR=1.8, 95%CI (1.1, 2.9), P=0.021], were risk factors for the long-term outcome. Conclusion DPLN patients with normal or slightly decreased renal function have a better long-term prognosis. Moderate to severe impairment of renal function, anemia and large crescents are associated with poor outcome. Key words: Lupus erythematosus, systemic; Lupus nephritis; End stage renal disease; Acute kidney injury; Crescent