Impact of Substantial Weight Loss on Digoxin Intoxication During Long-term Therapy

Despite numerous safety studies on digoxin, the association of substantial body weight loss with the development of digoxin intoxication and the transition of risk factors over time in patients on long-term digoxin treatment remain unclear.

This study aimed to reveal whether the risk factors of digoxin intoxication, including substantial body weight loss, change over the course of treatment.

A retrospective study was conducted in adult patients newly prescribed digoxin between January 2010 and December 2021. Multiple logistic analysis was performed to identify clinical features associated with digoxin intoxication over time.

A total of 329 patients followed for a median period of 139 (interquartile range, 29-909) days were selected for analysis. Among them, 36 patients (11%) developed digoxin intoxication. Multivariate analysis identified concomitant diuretics (odds ratio, 36.64; 95% confidence interval, 5.77-232.56), comorbid cancer (8.76; 1.95-39.31), estimated glomerular filtration rate (eGFR) reduction ≥ 30% from baseline (9.01; 2.31-35.16), and hemodialysis (47.30; 5.77-387.49) as risk factors associated with digoxin intoxication occurring within 6 months of digoxin treatment; while weight loss >6% during the last 6-12 months (16.07; 2.99-86.48), and eGFR reduction ≥ 30% from baseline (11.55; 2.37-56.35) were risk factors of intoxication occurring after 6 months of treatment.

Concomitant diuretics and comorbid cancer were risk factors of digoxin intoxication during early treatment, whereas substantial body weight loss ≥ 6% became the risk factor after prolonged treatment, and impaired renal function was the risk factor spanning early to prolonged treatment. Thus, transition of risk factors of digoxin intoxication during prolonged course of treatment was observed.