Spinal cord injury is associated with an increased risk of atrial fibrillation: A population-based cohort study

BACKGROUND Spinal cord injury (SCI) can result in substantial sensorimotor and autonomic dysfunctions and an adverse prognosis. Cardiovascular disease is the leading cause of death in patients with chronic SCI. OBJECTIVE We conducted a retrospective cohort study to investigate the association between atrial fibrillation (AF) and SCI. METHODS Using the National Health Insurance Research Database, we identified 41,691 patients without a history of AF who were newly hospitalized for SCI between 2000 and 2011. The comparison group included 166,724 patients without AF or SCI who were matched to the SCI group according to age, sex, and index year at a ratio of 4:1. Both cohorts were followed up until the end of 2011, and the cumulative incidence of AF was calculated. Univariate and multivariate Cox proportional hazards regression models and Kaplan-Meier curve analysis were used to compare differences in the cumulative incidence of AF between the 2 groups. RESULTS During the mean follow-up periods of 5.69 years for the SCI group and 6.17 years for the non-SCI group, the overall incidence rates were 2.70 and 1.99 cases per 1000 person-years, respectively (crude hazard ratio 1.36; 95% confidence interval 1.24-1.48). After adjusting for age, sex, and all comorbidities, the risk of AF remained significantly higher in the SCI group than in the non-SCI group (adjusted hazard ratio 1.28; 95% confidence interval 1.17-1.40). CONCLUSION SCI is associated with an increased risk of AF in a long-term follow-up period.