Contemporary management of anaemia, erythropoietin resistance and cardiovascular risk in patients with advanced chronic kidney disease: a nationwide analysis

BACKGROUND: Optimal management of chronic kidney disease (CKD) anaemia remains controversial and few studies have evaluated real-world management of anaemia in advanced CKD in the context of guideline recommendations. METHODS: We performed an observational study from the Swedish Renal Registry evaluating the epidemiology and treatment patterns of anaemia across Stages 3b–5 in non-dialysis (ND) and dialysis-dependent (DD) CKD patients during 2015. Logistic regression and Cox models explored the associations between anaemia treatments, inflammation, erythropoietin resistance index (ERI) and subsequent 1-year risk of major adverse cardiovascular events (MACEs). RESULTS: Data from 14 415 (ND, 11 370; DD, 3045) patients were included. Anaemia occurred in 60% of ND and 93% of DD patients. DD patients used more erythropoiesis-stimulating agents (ESAs; 82% versus 24%) and iron (62% versus 21%) than ND patients. All weekly ESA doses were converted to a weight-adjusted weekly epoetin equivalent dose. The prescribed ESA doses were low to moderate [median 48.2 IU/kg/week (ND), 78.6 IU/kg/week (DD)]. Among ESA-treated patients, 6–21% had haemoglobin (Hb) >13 g/dL and 2–6% had Hb <9 g/dL. Inflammation (C-reactive protein >5 mg/L) was highly prevalent and associated with ERI and higher ESA doses. Higher (>88 IU/kg/week) versus lower (<44 IU/kg/week) ESA doses were associated with a higher risk of MACEs [{ND hazard ratio [HR] 1.36 [95% confidence interval (CI) 1.00–1.86]; DD HR 1.60 [95% CI 1.24–2.06]}. There was no association between iron use and inflammation or MACEs. CONCLUSIONS: Anaemia remains highly prevalent in advanced CKD. Patients with anaemia received moderate ESA doses with a relatively low prevalence of iron use. Higher doses of ESA were associated with inflammation and a higher risk of MACE.