Red blood cell distribution width (RDW), a measure of variation in erythrocyte volume, has been associated with several cardiovascular disorders, but the relationship with atrial fibrillation (AF) remains unclear. We investigated the association between RDW and incidence of first hospitalization due to AF in a population-based cohort.
Red blood cell distribution width was measured in 27,124 subjects from the general population (age 45-73 years, 62% women) with no history of AF, heart failure, myocardial infarction or stroke. The association between baseline RDW and incidence of AF identified from the Swedish Hospital Discharge Register was evaluated.
During a mean follow-up of 13.6 years, 1894 subjects (53% men) were hospitalized with a diagnosis of AF. After adjustment for potential confounding factors, including cardiovascular disease risk factors, nutrient intake (iron, vitamin B12 and folate) and several haematological parameters (haemoglobin concentration, mean corpuscular volume and corpuscular haemoglobin content), the hazard ratio (HR) for incidence of AF was 1.33 [95% confidence interval (CI) 1.16-1.53] for the fourth versus first quartile of RDW (P for trend
