Effect of Spherical Adsorptive Carbon Among Chronic Kidney Disease Patients: A Nationwide Cohort Study

Spherical Adsorptive Carbon (SAC), a type of oral sorbent, is prescribed to chronic kidney disease (CKD) patients to remove uremic toxins. However, evidence regarding its effectiveness in delaying chronic kidney disease (CKD) progression remains insufficient. We aimed to evaluate the impact of SAC on CKD progression in patients with CKD stage 3 or higher using nationwide data. In this retrospective cohort study, we included patients diagnosed with CKD stage ≥3 from the Korea National Health Insurance System database between January 2020 and December 2022. Outcomes were compared between SAC users (N = 1289) and non-users (N = 1289) after 1:1 propensity score matching (PSM). After PSM, the time from index date to end-stage kidney disease (ESKD) was significantly longer in the SAC user group compared to the non-user group (246.8 days vs. 118.6 days, p < 0.001). In Cox regression analysis, the risk of ESKD was significantly lower in the SAC group (HR = 0.37, 95% CI: 0.29-0.48). However, the risk of dialysis initiation did not show a significant difference between the two groups (HR = 0.83, 95% CI: 0.27-2.59). This nationwide cohort study suggests that SAC treatment may delay progression from CKD stage 3 to ESKD, although it did not significantly reduce the risk of dialysis initiation.