Abstract: SA-PO245

Evaluation of the slope of Change in eGFR as a Treatment Response Variable in Lupus Nephritis

Session Information

Category: Glomerular

  • 1005 Clinical Glomerular Disorders

Authors

  • Bispo, Ingrid Romero, Rio de Janeiro State University, Rio De Janeiro, Rio de Janeiro, Brazil
  • Klumb, Evandro, Rio de Janeiro State University, Rio De Janeiro, Rio de Janeiro, Brazil
  • Suassuna, Jose H. R., Rio de Janeiro State University, Rio De Janeiro, Rio de Janeiro, Brazil
Background

In spite of treatment advances, up to 60% of lupus nephritis (LN) patients may eventually develop CKD. The commonest manifestations of LN include an active urinary sediment, proteinuria, and a loss of GFR. They are also the main tools determine treatment response, usually in a static fashion. We are not aware of any study that examined the predictive value of the slope of changes in renal function over time.

Methods

Out of 660 patients with SLE that attended our institution, between August of 2014 and June of 2016, we found and analyzed 227 patients with established LN. Estimated GFR by the CKD-EPI equation was evaluated longitudinally by linear regression and slopes calculated as ΔGFR in mL/min/month. Patients were grouped in tertiles of ΔGFR. Each tertile was analyzed by social-demographic, clinical, laboratorial and histopathologic features. Results were compared to treatment response variables as established in the literature. CKD and time to ESRD were analyzed as secondary outcomes.

Results

Women comprised 87% of the patients and mean age was 30 years. Proliferative GN predominated (77%) and mean of proteinuria at presentation was 3,6g/24h. The lowest tertile (worst response) was independently associated with race (Afro-Brazilians, p=0,05), lower levels of education (p=0,002) and with proliferative nephritides (p=0,03). Patients in this tertile also had more flares (p=0,003) but less active urinary sediment (p=0,03). On the other hand, the upper tertile (better response) was associated with higher education (p< 0,001), lower number of flares (p< 0,001), higher creatinine in the acute phase (p< 0,001). Subjects in low tertile and those that did not achieve complete response were more like to present CKD and ESRD.

Conclusion

The combination of traditional response variables along with slopes of change in GFR may provide an added discriminatory predictive value for evaluation of the treatment response in lupus nephritis.