Patients with chronic kidney disease (CKD) are more likely to develop atrial fibrillation(AF) than individuals with normal renal function, and are more likely to suffer ischaemic stroke(IS)/thromboembolism(TE). No prior study has considered the impact of eGFR on bleeding. We investigated the relationship of eGFR to IS/TE, mortality and bleeding in an AF population, unrestricted by age or comorbidity.
Patients with non-valvular AF (NVAF) were stratified into five categories according to eGFR(ml/min/1.73 m2): ≥90,60-89,30-59,15-29 and <15, analysing risk factors, all-cause mortality, bleeding and IS/TE. Of 8962 eligible individuals, 5912 had NVAF and available serum creatinine data, with 14499 patient-years of follow-up.
In non-anticoagulated and anticoagulated individuals, the incidence rates of IS/TE were 7.4 and 7.2 per 1000 person-years, respectively. Rates of all-cause mortality were 13.4 and 9.4 per 1000 person-years, respectively, and of major bleeding, 6.2 and 9.0 per 1000 person-years, respectively.Rates increased with decreasing eGFR with IS/TE rates being lower in individuals receiving OAC. eGFR was not an independent predictor of IS/TE on multivariate analyses. When the benefit of IS reduction is balanced against the increased risk of haemorrhagic stroke, the net clinical benefit (NCB) was clearly positive in favour of OAC use.
Incidence rates of IS/TE, mortality and bleeding increased with reducing eGFR, across the whole range of renal function. OAC use was associated with a lower incidence of IS/TE and mortality at 1 year, compared with non-anticoagulated individuals in all categories of renal function as measured by eGFR. The NCB balancing IS against serious bleeding was positive, in favour of OAC use amongst patients with renal impairment.