Prevalence of sleep disordered breathing across chronic kidney disease stages and eGFR quartiles. (A) SDB and CKD stages. (B) SDB and eGFR quartiles. CKD, chronic kidney disease; CKD stage 1–2, eGFR ≥ 60 mL/min/1.73 m2 with albuminuria; CKD stage 3, eGFR 30– 60 mL/min/1.73 m2; eGFR, glomerular filtration rate, estimated with the Chronic Kidney Disease Epidemiology Collaboration (CKD–EPI) formula; No CKD, eGFR ≥ 60 mL/min/1.73 m2 without albuminuria; Q1-Q4, quartiles of eGFR (30 to 72; 72 to 83; 83 to 93 and 93 to 127 mL/min/1.73 m2); SDB, sleep disordered breathing.