Self-care and renal dysfunction in patients with chronic heart failure

Abstract

Purpose: It has been shown that impaired renal function is a strong predictor of mortality in patients with chronic heart failure (HF). From a behavioural perspective, self-care has been assumed to be a crucial factor in chronic HF patients to maintain health. However, no prior studies have examined whether self-care is associated with improved renal function. Therefore, we prospectively examined the association between HF self-care and renal function at 1-year follow-up. Methods: In total, 482 chronic HF outpatients (mean age 66.2±9.5 years, 74% men) were recruited from 4 teaching hospitals in the Netherlands. All patients completed the shortened 9-item version of the European Heart Failure Self-care Behaviour scale to assess HF self-care and consultation behaviour at baseline and at 1-year follow-up. Renal function was measured at both consecutive time points using glomerular filtration rates of creatinine. Other HF-related pathophysiological markers of HF disease progression were also measured at both time points including heart pump function (left ventricular ejection fraction and brain natriuretic peptide), liver function, and anemia. Results: By means of linear mixed modeling using maximum likelihood estimation, better HF self-care and consultation behaviour were associated with lower glomerular filtration rates over time (p=.009 and p=.06, respectively), indicating worse renal functioning even after controlling for age, sex, disease severity using New York Heart Association functional class, and standard risk factors. In contrast, regular physical activity was associated with better renal function (p=.03). HF self-care was not associated with other pathophysiological markers of disease severity. Conclusions: HF self-care was associated with renal dysfunction over time. While there was no association between self-care and other pathophysiological markers of HF disease severity, physical activity activity was associated with improved renal function over time. Patient's awareness of their renal dysfunction might prompt better self-care, but the true nature of the link between self-care and clinical outcomes in patients with chronic HF warrants more attention in future research.