Methods and results
We retrospectively enrolled 1768 AF patients in our study. Demographic characteristics, laboratory data and echocardiography were measured and collected on admission. The primary endpoints were death from all causes and death from cardiovascular diseases. The secondary endpoints were major bleeding and stroke. During a mean follow-up of 22.35 months, 155 patients occurred death from all causes. For further analysis, patients were categorized into two groups according to the optimal cutoff value of SII level determined by using receiver operating characteristics curve analysis (low SII group <451.01 or high SII group ≥451.01). The incidence of death from all causes and death from cardiovascular diseases in high SII group is significantly higher compared with that in low SII group, (14.3% vs. 5.3%,p <0.001; 9.3% vs. 3.8%, p <0.001, respectively). However, no significant differences were detected between two groups for the secondary endpoints (p >0.05). On multivariable Cox analysis with adjustment of potential confounders, the risk of death from all causes and death from cardiovascular diseases increased by 77.6% (hazard risk [HR]=1.776, 95% confidence interval [CI]: 1.109-3.065, p = 0.018) and 51.2% (HR=1.512, 95%CI: 1.011-3.742, p = 0.025), respectively, in high SII group.