Incident atrial fibrillation and risk of death in adults with chronic kidney disease

Abstract

Background: Atrial fibrillation (AF) frequently occurs in patients with chronic kidney disease (CKD); however, the long-term impact of development of AF on the risk of death among patients with CKD is unknown.

Methods and results: We studied adults with CKD (glomerular filtration rate <60 mL/min per 1.73 m(2) by the Chronic Kidney Disease Epidemiology Collaboration equation) identified between 2002 and 2010 who were enrolled in Kaiser Permanente Northern California and had no previously documented AF. Incident AF was identified using primary hospital discharge diagnoses or ≥2 outpatient visits for AF. Death was comprehensively ascertained from health plan administrative databases, Social Security Administration vital status files, and the California death certificate registry. Covariates included demographics, comorbidity, ambulatory blood pressure, laboratory values (hemoglobin, proteinuria), and longitudinal medication use. Among 81 088 adults with CKD, 6269 (7.7%) developed clinically recognized incident AF during a mean follow-up of 4.8±2.7 years. There were 2388 cases of death that occurred after incident AF (145 per 1000 person-years) compared with 18 865 cases of death during periods without AF (51 per 1000 person-years, P<0.001). After adjustment for potential confounders, incident AF was associated with a 66% increase in relative rate of death (adjusted hazard ratio 1.66, 95% CI 1.57 to 1.77).

Conclusion: Incident AF is independently associated with an increased risk of death in adults with CKD. Further study is needed to understand the mechanisms by which CKD is associated with AF and to identify potentially modifiable risk factors to decrease the burden of AF and subsequent risk of death in this high-risk population.

Keywords: atrial fibrillation; kidney disease; mortality.

Figure 1.

Multivariable association between atrial fibrillation and risk of death among chronic kidney disease subgroups. Models included age, sex, race, education, income level, eGFR level, albuminuria, hemoglobin, diabetes mellitus, hypertension, coronary heart disease, ischemic stroke, transient ischemic attack, heart failure, peripheral arterial disease, dyslipidemia, chronic lung disease, chronic liver disease, hyperthyroidism, and baseline medication use (beta blockers, angiotensin‐converting enzyme inhibitors or angiotensin receptor blockers, calcium channel blockers, diuretics, statins, other lipid lowering agents, warfarin, antiplatelet agents). eGFR indicates estimated glomerular filtration rate; HR, hazard ratio.