Background: This study aimed to evaluate the association between the neutrophil to-lymphocyte ratio (NLR) and outcome of septic patients with atrial fibrillation. Methods: Patients with sepsis and AF from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database had their baseline data and in-hospital prognosis retrieved. Multivariable logistics regression analyses were applied to calculate adjusted odds ratios (OR) with 95% confidence intervals (CI). Survival curves were plotted, and subgroup analyses were stratified by relevant covariates. To address the linearity relationship, curve fitting were performed. Results: Of the 7,241 patients, 5,864 patients with sepsis and AF were included. The overall in-hospital mortality rate was 21.1% (1,235/4,629). Adjusted for confounding factors in the multivariable logistics regression analysis models, when NLR was used as a categorical variable, patients in the highest NLR tertile had increased in-hospital mortality compared to patients in the lowest NLR tertile (HR = 1.31, 95% CI: 1.09–1.58). A linear relationship between NLR and in-hospital mortality was found in patients with sepsis and AF. K-M curves showed the in-hospital mortality rate was highest in group 3(NLR＞=8.4) than in the other two groups. Stratified analyses indicated that the correlation between the NLR and in-hospital mortality was stable. Conclusion: There is a linear relationship between NLR and in-hospital mortality in intensive care of septic patients with atrial fibrillation. A higher NLR in ICU patients is associated with in-hospital mortality in the United States. However, further research is needed to confirm the findings.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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