Prognostic value of plasma renin activity in heart failure patients with chronic kidney disease

Abstract

Background: Impairment of kidney function is frequently observed in chronic heart failure (CHF). It correlates with clinical and neurohormonal status, and affects prognosis. We aimed to identify the prognostic impact of plasma renin activity (PRA) in patients affected by CHF with chronic kidney disease (CKD).

Methods: We enrolled 996 consecutive CHF patients (age 65 ± 13 years, mean ± SD, left ventricular ejection fraction, LVEF, 33 ± 10%), who underwent a complete clinical and neurohormonal characterization and were then followed-up (median 36 months) for the end point of cardiac death.

Results: A stage ≥ 3 CKD (estimated glomerular filtration rate <60 mL/min/1.73 m(2)) was found in 437 patients. Impaired renal function was associated with worse symptoms, lower LVEF, higher plasma norepinephrine, NT-proBNP and PRA (all p<0.001). As compared to patients with preserved renal function, those with CKD had higher cardiac mortality [106 (24%) vs 53 (9.5%), p<0.001]. In CKD patients, at Cox multivariate analysis, only ejection fraction (HR 0.91, 95% CI 0.84-0.97, p=0.008), NT-proBNP (2.53, 1.45-4.41, p=0.001) and PRA (1.73, 1.16-2.58, p=0.007) were independent predictors of cardiac death. ROC analysis identified a cut-off value for PRA of 3.29 ng/mL/h that predicted prognosis with the greatest accuracy. Finally, the elevation of both NT-proBNP and PRA identified a subset of patients with the highest risk of cardiac death.

Conclusions: PRA has an independent prognostic value in CHF patients with CKD comorbidity. The combination of PRA and NT-proBNP identifies a group of high risk patients, who might benefit of a more intensive care, targeted to enhance renin-angiotensin system antagonism.

Keywords: Chronic heart failure; Chronic kidney disease; Natriuretic peptides; Plasma renin activity; Renin–angiotensin system.