The effect of digoxin on renal function in patients with heart failure

Introduction Digoxin is used in patients with chronic heart failure (CHF) who remain symptomatic despite optimal medical treatment. Impaired renal function is commonly associated with CHF. We investigated the relation between digoxin use and change in renal function over time in patients with CHF. Methods One thousand two hundred forty-one patients with symptoms and signs of CHF (average age 72 years (64% male), and median NTproBNP 1426 ng/l (interquartile range 632-2897) were divided into four groups: never on digoxin (N = 394); digoxin throughout (N = 449); started digoxin at some point after baseline (N = 367); and stopped digoxin at some point after baseline (N = 31). The rate of change of estimated glomerular filtration rate (eGFR) was calculated using linear regression. Results Patients on digoxin throughout had a significantly greater rate of decline in eGFR per year than patients not on digoxin throughout (mean (+/- standard deviation); - 5 (14) ml/min/1.73m(2) per year v - 2 (11) ml/min/1.73m(2) per year, P = 0.02). In those patients who started digoxin during follow up, there was no significant difference in the rate of decline in eGFR before and after starting digoxin. There was no correlation between baseline eGFR (or rate of decline in eGFR) and age, haemoglobin or NTproBNP. Compared to patients taking both angiotensin-converting-enzyme inhibitor (ACEi) or angiotensin receptor blockers (ARB) and beta-blocker (BB), patients who were not taking an ACEi/ARB or BB had a numerically faster rate of decline in eGFR, although this was not statistically significant. Conclusion The rate of decline in renal function is greater in patients with CHF who are taking digoxin.