Proteinuria Reductions Improve Rare Kidney Disease Outcomes

Reducing proteinuria could help to significantly slow the speed of kidney function decline in patients with focal segmental glomerulosclerosis (FSGS), a rare glomerular disease involving scarring of the kidneys. 

While full remission of proteinuria has been shown to decrease the speed of disease progression among patients with FSGS, it is not clear whether smaller reductions in proteinuria could also benefit these patients.

To examine this further, the researchers conducted a cohort analysis of 138 patients with steroid resistant FSGS who had been enrolled in a randomized treatment trial comparing cyclosporine with mycophenolate mofetil plus dexamethasone.

Overall, the researchers found that any changes in proteinuria during the study period were significantly associated with kidney function as measured by estimated glomerular filtration rate (eGFR). Specifically, a 1-unit reduction in the patient’s urinary protein to creatinine ratio was associated with a rise in eGFR of 3.90 ml/year. The hazard ratio for end-stage kidney disease or death per unit reduction in this ratio was 0.23 (95% CI=0.12 to 0.44).

“These findings provide evidence for the benefit of urinary protein reduction in FSGS. Reductions in proteinuria warrant further evaluation as a potential surrogate for preservation of kidney function that may inform the design of future clinical trials,” they concluded.

—Michael Potts

Reference:

Troost JP, Trachtman H, Spino C, et al. Proteinuria reduction and kidney survival in focal segmental glomerulosclerosis. Published online August 10, 2020. AJKD. doi:10.1053/j.ajkd.2020.04.014