Prevalence, Resource Utilization and Economic Impact of Kidney Function and Proteinuria in Patients with Focal Segmental Glomerulosclerosis

Abstract

Background: Among patients with focal segmental glomerulosclerosis (FSGS), proteinuria and kidney function decline may be associated with increased economic burden. This study aimed to provide current information on the epidemiology and economic burden of FSGS in the United States.Methods: Descriptive, non-interventional, retrospective cohort study. Overall, 9899 patients were identified between January 2016 and December 2020 in Optum® de-identified Market Clarity Data based on International Classification of Diseases code or Optum® proprietary Natural Language Processing data. Descriptive statistics were reported for categorical and continuous variables. Prevalence estimates were standardized to the age, gender, and race/ethnicity distribution of the general United States population using direct methods and data from the 2021 United States Census Bureau. Per-patient-per-month healthcare resource utilization and associated costs, in 2020 United States dollars were reported by proteinuria (≤ 1.5 g/g vs. >1.5 g/g or < 3.5 g/g vs. ≥3.5 g/g) and chronic kidney disease stage (stage 1–5/kidney failure). The Fisher's Exact Test was used for categorical healthcare resource utilization outcomes, and linear regression (mean) and the Jonckheere-Terpstra Test (medians) were used for continuous healthcare resource utilization and cost outcomes.Results Estimated annual United States prevalence (average for 2016–2020) was 212.6 per 1 000 000. There was a consistent trend toward higher healthcare resource utilization and total costs with both chronic kidney disease progression (stage 1–5/kidney failure) and higher levels of proteinuria (≤ 1.5 g/g vs. >1.5 g/g or < 3.5 g/g vs. ≥3.5 g/g).Conclusions The observed prevalence of FSGS increased in the US and was highest among African Americans. Both more advanced chronic kidney disease and higher levels of proteinuria were associated with higher healthcare resource utilization and costs. Treatments which reduce proteinuria and slow kidney function decline have potential to reduce the economic burden associated with FSGS.