Effects of mineralocorticoid receptor antagonists on new-onset or recurrent atrial fibrillation: a Bayesian and frequentist network meta-analysis of randomized trials

Abstract Aims Clinical and translational research suggests that mineralocorticoid receptor antagonists (MRAs) may prevent atrial fibrosis and electrical remodeling associated with atrial fibrillation (AF). This study aimed to consolidate existing evidence from randomized controlled trials (RCTs) evaluating the effect of MRAs on incident or recurrent AF. Methods Medline, Cochrane Library and Scopus were searched until February 12, 2024. Triple-independent study selection, data extraction and quality assessment were performed. Evidence was pooled using both pairwise and Bayesian and frequentist network meta-analyses. Results Twenty-three RCTs (13,358 participants) were identified. Based on the pairwise random effects meta-analysis, MRAs were associated with a significant reduction in AF events compared to placebo or usual care (risk ratio {RR}= 0.75; 95% confidence interval {CI}= [0.66, 0.87]; P< 0.001; I2= 3%). This protective effect was robust both for new-onset and recurrent AF episodes (subgroup p-value= 0.69), while the baseline HF status was not a significant effect modifier (subgroup p-value= 0.58). MRAs demonstrated a significantly higher reduction in AF events for patients with chronic renal disease compared to placebo (RR= 0.78; 95% CI= [0.62, 0.98]; P= 0.03; I2= 0%). The network meta-analyses revealed that only spironolactone was associated with a significant reduction in AF events (Bayesian RR= 0.76; 95% CI= [0.65, 0.89]; P< 0.001; level of evidence moderate; SUCRA 0.731), while eplerenone and finerenone showed a neutral effect. Conclusion MRAs confer a significant benefit in terms of reducing incident or recurrent AF episodes, irrespective of HF status. In this context, spironolactone may be preferable compared to eplerenone or finerenone.