Impaired renal function affects clinical outcomes and management of patients with heart failure

Abstract

Aims: Inpatients with heart failure and renal impairment have poor outcomes and variable quality of care. We investigate treatment practice and outcomes in an unselected real-world cohort using historical creatinine measurements.

Methods and results: Admissions between 1/4/2013 and 30/4/2015 diagnosed at discharge with heart failure were retrospectively analysed. Stages of chronic kidney disease (CKD) and acute kidney injury (AKI) were calculated from creatinine at discharge and 3-12 months before admission. We identified 1056 admissions of 851 patients (mean age 76 years, 56% Caucasian, 36% with diabetes mellitus, 54% with ischaemic heart disease, and 57% with valvular heart disease). CKD was common; 36%-Stage 3a/b, 11%-Stage 4/5; patients were older, more often diabetic, with higher potassium, lower haemoglobin, and more oedema but similar prevalence of left ventricular systolic dysfunction (LVSD) compared patients with Stages 0-2. AKI was present in 17.0% (10.4%-Stage 1, 3.7%-Stage 2, and 2.9%-Stage 3); these had higher potassium and lower haemoglobin than patients with no AKI. Length of stay was longer in Stage 4/5 CKD [11 days; P = 0.008] and AKI [13 days; P = 0.006]. Mortality was higher with Stage 4/5 CKD (13.8% compared with 7.7% for Stages 0-2 CKD (P = 0.036)] and increased with AKI (5%-no AKI, 20.9%-Stage 1, 35.9%-Stage 2, and 48.4%-Stage 3; P < 0.001). Adjusted for age, diabetes, and LVSD, both AKI and Stage 4/5 CKD were independent predictors of in-hospital mortality. In survivors with LVSD, the discharge prescription of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers decreased with progressive CKD, [84%-no-mild, 59%-moderate, and 36%-severe CKD; P < 0.001]; this was not purely explained by hyperkalaemia.

Conclusions: Inpatients with heart failure and renal impairment, acute and chronic, failed to receive recommended therapy and had poor outcomes.

Keywords: Epidemiology; Heart failure; Kidney; Mortality.

Figure 1

Use of medications with different stages of chronic kidney disease in patients with left ventricular systolic dysfunction. ACE, angiotensin‐converting enzyme inhibitor; ARB, angiotensin receptor blocker; CKD, chronic kidney disease; MRA, mineralocorticoid receptor antagonist. No‐mild CKD, no CKD or CKD Stages 1–2; moderate CKD, CKD Stages 3a–3b; severe CKD, CKD Stages 4–5.

Figure 2

Lack of angiotensin‐converting enzyme inhibitor/angiotensin receptor blocker therapy with increasing serum potassium in patients with left ventricular systolic dysfunction. Showing percentage of patients not on angiotensin‐converting enzyme inhibitor/angiotensin receptor blocker with rising levels of serum potassium, separately in patients above and below estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73m². K, serum potassium in mmol/L.

Figure 3

Lack of mineralocorticoid use with increasing serum potassium in patients with left ventricular systolic dysfunction. Showing percentage of patients not on mineralocorticoid receptor antagonist with rising levels of serum potassium in patients above and below an estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73m². K, serum potassium in mmol/L.