Role of comorbidities in heart failure prognosis Part 2: Chronic kidney disease, elevated serum uric acid

Abstract

Despite improvements in pharmacotherapy, morbidity and mortality rates in community-based populations with chronic heart failure still remain high. The increase in medical complexity among patients with heart failure may be reflected by an increase in concomitant non-cardiovascular comorbidities, which are recognized as independent prognostic factors in this population. Heart failure and chronic kidney disease share many risk factors, and often coexist. The presence of kidney failure is associated with incremented risk of cardiovascular and non-cardiovascular mortality in heart failure patients. Chronic kidney disease is also linked with underutilization of evidence-based heart failure therapy that may reduce morbidity and mortality. More targeted therapies would be important to improve the prognosis of patients with these diseases. In recent years, serum uric acid as a determinant of cardiovascular risk has gained interest. Epidemiological, experimental and clinical data show that patients with hyperuricaemia are at increased risk of cardiac, renal and vascular damage and cardiovascular events. Moreover, elevated serum uric acid predicts worse outcome in both acute and chronic heart failure. While studies have raised the possibility of preventing heart failure through the use of uric acid lowering agents, the literature is still inconclusive on whether the reduction in uric acid will result in a measurable clinical benefit. Available evidences suggest that chronic kidney disease and elevated uric acid could worsen heart failure patients' prognosis. The aim of this review is to analyse a possible utilization of these comorbidities in risk stratification and as a therapeutic target to get a prognostic improvement in heart failure patients.

Keywords: Heart failure; comorbidities; kidney; prognosis; risk stratification; uric acid.

Figure 1.

Multivariate adjusted geometric mean peak VO₂ with 95% confidence interval according to strata of estimated glomerular filtration rate (eGFR). (Adapted from Scrutinio et al.)VO₂: maximum rate of oxygen consumption.

Figure 2.

Kaplan–Meier survival curves in the three subgroups of estimated glomerular filtration rate (eGFR), stratified by peak VO₂. (Adapted from Scrutinio et al.)VO₂: maximum rate of oxygen consumption.

Figure 3.

Receiver operating characteristic (ROC) curve for cardiovascular mortality (left diagram) and total mortality (right diagram) for MECKI score and for MECKI score + serum uric acid. Red curve: ROC curve for the MECKI score; green curve: ROC curve for the MECKI score combined with serum uric acid level. (Adapted from Piepoli et al.) MECKI: Metabolic Exercise Cardiac Kidney Index; AUC: area under the curve.