**2. Epidemiology**

The 2010 Global Burden of Disease (GBD) study estimated that the prevalence of AF approximated at 33.5 million individuals worldwide [1]. In particular, AF is believed to affect between 2.2 and 5.0 million Americans, 4.5 million Europeans and is estimated to affect 1.4% of Australians [1, 2]. The prevalence of AF is expected to increase globally over the next decade [3]. The prevalence of AF increases with age, occurring in approximately 1% of the population under 60 years of age and 15% of the population over 80 years of age. Furthermore, the age-adjusted prevalence of AF is higher for men than women [1, 4]. In terms of complications of AF, ischemic stroke is the most common cause of cerebrovascular incident with 75% of these strokes directly linked to AF [3]. In addition, proportion of strokes from embolic sources increases with age, and greater than 35% of strokes in patients over 80 years of age are cardiac in origin, predominantly due to AF [3], making AF the commonest cause of stroke in this patients older than 80 years [1, 3, 4].

The health burden of renal disease is high for patients as well as for health services globally. The 2010 GBD study found that chronic kidney disease (CKD), which previously ranked 27th in the list of causes of total number of global deaths in 1990, ranked 18th in 2010 [1, 5]. The incidence and prevalence of ESKD vary significantly across different countries. The incidence of ESKD is increasing, with reports indicating doubling in the number of patients being treated for ESKD in Europe, the Americas, and Australia, with diabetes and hypertension being the most common causes in developed and many developing countries; however, glomerulonephritis and "undetermined causes" were more common in Asia and sub-Saharan Africa [5].

Cardiovascular disease and its sequelae occur more frequently in patients with CKD, compared to the general population, and it is often more severe [6]. Patients with impaired renal function (estimated glomerular filtration rate (eGFR) ≤80 mL/min) are deemed to be at higher risk for all cardiovascular events. Current literature examining the prevalence of AF in hemodialysis (HD) patients varies widely, describing a range from 7 to 27% [4]. Furthermore, paroxysmal AF was present in 3.5%, persistent AF in 9.6% of patients and permanent AF in 13.9% of patients [4]. In a large cohort study conducted by Cheng-Huang et al., the prevalence of AF in patients receiving peritoneal dialysis and HD was examined [7]. The incidence rate ratios for AF were 2.07 and 1.78 in HD and PD groups, respectively. Additionally, after adjusting for age, gender and comorbidities, the hazard ratios for the AF risk were 1.46 and 1.32 in HD and PD groups, respectively.

In particular, in a study reported by Hohnloser et al., the risk of stroke in patients with CKD increased with decreasing eGFRs, the annual stroke rate was 1.05% in patients with an eGFR of >80 mL/min, 1.46% in patients with an eGFR of 50–80 mL/min and 2.39% in patients with an eGFR of ≤50 mL/min [8].
