REN and chronic kidney disease: Some potential mediators between AF and adverse outcomes like the hormones in the renin-angiotensin-aldosterone system were not examined, the previous episodes of atrial fibrillation were not recorded in our study and some factors like anticoagulation therapy information were also not included in the dataset, as those treatments might influence the incidence of hemorrhagic stroke, it should be paid great attention while applying them in the patients with CKD, these shortages were hopefully added in our future exploration.