Burden of chronic kidney disease and outcomes following hospitalisation for heart failure

BACKGROUND: The epidemiology and long-term healthcare utilisation associated with chronic kidney disease (CKD) among those with heart failure (HF) has not been mapped. METHODS: This is a 5-year longitudinal cohort analysis of patients hospitalised for HF and enrolled in the Patient Centered Care Transitions in HF randomised controlled trial. We compared clinical events, healthcare resource utilisation and direct healthcare costs (Canadian dollars, adjusted for inflation) between those with and without a CKD diagnosis at index hospitalisation. Diagnoses and outcomes were determined from linked, administrative databases. Survival was evaluated using Cox-proportional hazards models adjusted for baseline variables. RESULTS: Among 4441 patients hospitalised for HF, 929 (20.9%) had an established CKD diagnosis at index hospitalisation. Patients with CKD at index HF hospitalisation faced a higher adjusted risk of death (adjusted HR 1.55, 95% CI 1.42 to 1.69), poorer survival (mean [SD] 2.2 [1.8] vs 3.0 [1.9] years), more rehospitalisations (mean [SD] 4.5 [12.2] vs 2.5 [6.6] per patient) and more in-hospital days (mean [SD] 43.8 [61.8] vs 22.7 [42.3] per patient) than those without a diagnosis of CKD. Patients with a CKD diagnosis at index hospitalisation received more ambulatory and diagnostic services and were less likely to be dispensed an ACE inhibitor or mineralocorticoid receptor antagonist after adjusting for relevant baseline characteristics. Annual healthcare costs were nearly two times as high in patients with CKD at index hospitalisation than those without (mean [SD] $C128 840 [137 611] vs $C67 937 [104 149] $C/year), largely due to rehospitalisations. Among those without CKD at baseline, at least 83.4% received a CKD diagnosis during the follow-up period. CONCLUSIONS: CKD is common at index hospitalisation for HF and is associated with a higher risk of death, shorter lifespan, more rehospitalisations and nearly twice the direct healthcare costs than no CKD. A vast majority of patients without CKD at index hospitalisation for HF are diagnosed with it subsequently.