Giving statins to women with established coronary disease reduces their odds of developing atrial fibrillation (AF), a large observational study has shown. The study cohort was taken from the Heart and Estrogen/Progestin Replacement Study (HERS). In total, 2,673 postmenopausal women with stable coronary disease were enrolled. The main outcome measure was AF prevalence at baseline and incident AF over a mean follow-up of four years.