Achieving complete or partial remission of proteinuria is associated with better long-term outcomes in patients with focal segmental glomerulosclerosis (FSGS), according to a study published in the Clinical Journal of the American Society of Nephrology.
Data on 466 patients with primary FSGS with proteinuria were analyzed from five independent cohorts. The researchers categorized Proteinuria by months 1, 4, and 8 after study baseline using conventional definitions of complete (< 0.3 g/g), and partial remission (< 3.5 g/g and 50% reduction in proteinuria). They used receiver operating curves to assess novel remission definitions, and Kaplan–Meier methods were used to estimate the associations of proteinuria with progression to ESRD or a reduction in kidney function.
The findings showed that conventional partial remission was not associated with kidney survival. However, a novel definition of partial remission (40% proteinuria reduction and proteinuria < 1.5 g/g) on the basis of receiver operating curve analyses of 89 patients was identified (Sensitivity = 0.70; Specificity = 0.77), was associated with better prognosis (13 out of 71 progressed; 8.5 per 100 patient-years). Also, complete remission was correlated with better prognosis (6 out of 41 patients progressed to kidney failure; 6.6 per 100 patient-years), compared with those with no response (51 out of 116 progressed; 20.1 per 100 patient-years). Conventional partial remission at month 8, but not month 4, was also associated with better response (19 out of 85 patients progressed; risk = 10.4 per 100 patient-years), the researchers noted.
“We describe the development of a novel FSGS proteinuria reduction metric derived from a large, clinically representative, pooled cohort of patients with primary FSGS that correlated with kidney survival,” the researchers wrote. “Adoption of this metric for use in clinical practice may enable nephrologists to assess the response to treatment and prognosis of individual patients more accurately.”
They added that, “If approved by regulatory agencies upon further validation, then incorporation of the end point into the study design and statistical plan may enable more efficient completion of randomized clinical trials designed to test novel therapies for patients with FSGS.”