KDIGO-defined kidney dysfunction predicts long-term outcomes in a multicenter cohort of adults with sickle cell disease

Approximately 15% of deaths in adults with sickle cell disease (SCD) are attributed to kidney failure. Although urine albumin-to-creatinine ratio (UACR) is recommended to screen for kidney damage, its utility in predicting long-term complications in SCD remains unclear. We investigated whether "Kidney Disease: Improving Global Outcomes (KDIGO)" algorithms used to assess kidney disease in the general population predicted chronic kidney disease (CKD) progression and mortality in a longitudinal cohort of 379 adults with SCD from 2 academic institutions. KDIGO criteria include UACR detected in 2 consecutive measurements ≥3 months apart and a heat map integrating UACR with estimated glomerular filtration rate. KDIGO-defined CKD was present in 39.8% of individuals in our SCD cohort. Over a median follow-up of 3.3 years, incremental KDIGO-defined UACR category independently predicted a twofold greater risk of CKD progression and 1.8-fold greater risk of mortality (P ≤ .05). KDIGO-defined CKD heat map strengthened the ability to predict CKD progression and mortality risk (P ≤ .0087). Our data provide clinical support for the screening utility of UACR based on repeated abnormal values ≥3 months apart. The KDIGO heat map further refines the risk of long-term outcomes among adults with SCD and should be applied to guide future studies for monitoring and intervention strategies.