Spironolactone is associated with reduced risk of new-onset atrial fibrillation in patients receiving renal replacement therapy

Objectives: Whether the spironolactone treatment remains effective for the prevention of atrial fibrillation (AF) in dialysis patients is unclear. Methods: We used a database from the Registry for Catastrophic Illness from the National Health Research Institute. All dialysis patients aged 18 or older without history of AF before ESRD were incorporated. A total of 113,191 dialysis patients were enrolled in the study. The median follow-up time was 4.17 years. We collected information on prescribed drug dosage, number of days of treatment and the total number of pills dispensed from the outpatient pharmacy prescription database. All individuals in the study cohort with the first occurrence of AF were included as cases. Results: In spironolactone group, the incidence of developing new AF was significantly lower than that in the control group both before (0.8% vs. 3.3%, P = 0.019) and after PS matching (1.2% vs. 3.0%, P = 0.019). Before PS matching, Cox's proportional hazard regression analyses showed that spironolactone was associated with 60% reduction of new AF (HR = 0.372 [0.200-0.692], P = 0.002) and the protective effect is dose-responsive in accumulated dose, treatment duration and mean daily dose. After PS matching, the overall AF prevention effect remained significant (HR = 0.400 [0.179-0.895], P = 0.026) while the dose-response relationship became borderline significant. Subgroup analyses showed that the protective effect was more evident in some specific subgroup patients. Conclusion: Our study showed that spironolactone therapy was associated with lower risk of developing AF in a dose-responsive manner in patients with dialysis. Further randomized study is needed to confirm this observation.