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 to predict 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 SCD adults from two academic institutions. KIDGO criteria include UACR detected in two 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 2-fold greater risk of CKD progression and 1.8-fold greater risk of mortality (P≤0.05). KDIGO-defined CKD heat map strengthened the ability to predict CKD progression and mortality risk (P≤0.0087). Our data provides clinical support for the screening utility of UACR based on repeated abnormal values ≥3 months apart. The KDIGO-heat map further refines risk of long-term outcomes in adults with SCD and should be applied to guide future studies for monitoring and intervention strategies.
Zhang et al. (Tue,) studied this question.