Renal Function and Exercise Training in Ambulatory Heart Failure Patients With a Reduced Ejection Fraction - Findings From the HF-ACTION Randomized Controlled Trial

Background: It has previously been shown that patients with chronic kidney disease and heart failure (HF) have progressively lower measures of fitness with declining estimated glomerular filtration rate (eGFR). However, the impact of a structured aerobic exercise intervention on outcomes among ambulatory HF patients with comorbid CKD is unknown.Methods: HF-ACTION enrolled 2331 outpatients with HF and an ejection fraction (EF) <35% and randomized them to aerobic exercise training vs. usual care. Patients were grouped according to the presence of CKD, defined as an eGFR <60 mL/min/1.73 m2 at baseline. The association between CKD and outcomes was assessed using multivariable Cox proportional hazard models.Results: The prevalence of CKD was 41% at baseline. Patients with CKD tended to be older and Caucasian, have a higher burden of medical comorbidities including diabetes mellitus, and were more likely to report NYHA functional class III/IV. In addition, HF patients with comorbid CKD also experienced more modest improvements in functional status as assessed by 6-minute walk distance (effect estimate -6.5 m, 95% confidence interval [CI] -12.6 m, -0.4 m; p-value = 0.04) from baseline to 3 months and quality of life as measured by the Kansas City Cardiomyopathy Questionnaire (effect estimate -2.7, 95% CI -4.2, -1.1; p-value = <0.001) from baseline to 12 months. Among patients with and without CKD, respectively, the incidence of the primary outcome was 75% and 63% over a median follow-up of 30 months (Figure). CKD was independently associated with increased risk of all-cause death or hospitalization (hazard ratio 1.18, 95% CI 1.04-1.33; p-value = <0.01). CKD status did not modify the relationship between treatment arm and the primary outcome (p-value for interaction = 0.48).Conclusion: The prevalence of CKD was high among ambulatory HF patients with a reduced EF and was associated with a poor prognosis but did not modify the effect of aerobic exercise training.Author Disclosures: A.P. Ambrosy: None. H. Mulder: None. A. Coles: None. W.E. Krauss: None. C.S. Lam: None. P.A. Mccullough: None. I. Pina: None. J. Tromp: None. D.J. Whellan: None. C.O. Connor: None. R.J. Mentz: None.

Duke Scholars

Author Robert John Mentz Medicine, Cardiology