Among patients with CKD, the prevalence of AF is substantially higher than in the general population, ranging from 16% to 21% in nondialysis dependent CKD and 15% to 40% in patients Among patients with AF, CKD is present in one-third of patients at the time of AF diagnosis51,429 although this may be substantially higher among cohorts of prevalent AF subjects. The impact of AF is illustrated in the systematic review by Odutayo et al,51 whereby the presence of AF increased CKD (HR, 1.64; 95% CI, 1.41 to 1.91), as well as major cardiovascular events (RR, 1.96; 95% CI, 1.53-2.51), sudden cardiac death (RR, 1.88; 1.36-2.60), HF (RR, 4.99; 95% CI, 3.04-8.22), and PAD (RR, 1.31; 95% CI, 1.19-1.45). AF, CKD, and Stroke: CKD increases the baseline risk of ischemic stroke in patients with AF.428 The pathophysiological mechanisms responsible for stroke and systemic embolism in these patients are multifactorial. The precise attributable risk of AF as a causal agent of cardioembolic stroke is therefore unclear, particularly where patients have substantially higher risk of atherothrombotic ischemic stroke due to hypertension, intracranial and carotid atherosclerosis, HF, and CAD. Second, CKD increases the competing risk of death from causes unrelated to AF-associated stroke and may attenuate expected bene t of stroke prevention therapy. 