Neutrophil-lymphocyte ratio and risk of atrial fibrillation after thoracic surgery

Postoperative atrial fibrillation (POAF) occurs frequently in patients after noncardiac thoracic surgery and has been associated with increased morbidity and risk of stroke. Recent studies have shown conflicting results on the role of neutrophil-lymphocyte ratio (NLR) and its association with the development of POAF after cardiac surgery. Our goal was to determine whether an association exists between NLR and the incidence of POAF after non-cardiac thoracic surgery.

Using a database of 259 consecutive patients age 60 or older who had anatomic lung resection or oesophagectomy for oncologic resection, we compared preoperative, postanaesthesia care unit and postoperative day 1 NLR between patients who did and did not develop POAF during their hospitalization using Fisher's exact test or logistic regression. We also compared NLR in patients who underwent minimally invasive resection versus open surgery.

POAF occurred in 50/259 (19%) of patients during their hospitalization. There were no significant differences in NLR between patients who did and did not develop POAF. In a secondary analysis of 180 patients who underwent open anatomic lung resection or oesophagectomy and 79 who underwent minimally invasive anatomic lung resection there was no difference in preoperative or immediate postoperative NLR, or an interaction in terms of odds of developing POAF.

In contrast to cardiac surgery, in patients undergoing major non-cardiac thoracic surgery, we had no evidence to show that either preoperative or early postoperative NLR was associated with the development of POAF.