Updated evidence on peri-operative neutrophil-to-lymphocyte ratio in cardiac surgery: A dual analysis of prognostic and diagnostic value for post-operative atrial fibrillation.
Mohamed K A Awad, Ahmed E Ali, Muhammad S Mazroua et al.
✦ AI-curated · Sources linked
In 30 seconds
This systematic review and meta-analysis assessed whether peri-operative neutrophil-to-lymphocyte ratio (NLR) is associated with new-onset post-operative atrial fibrillation (POAF) in adults undergoing cardiac surgery. Across 27 studies excluding patients with pre-operative atrial fibrillation, POAF was associated with higher pre-operative NLR (standardized mean difference [SMD] 0.51; 95% CI 0.34-0.67; P < .001). Post-operative NLR was also higher in POAF patients. Diagnostic analysis found moderate predictive accuracy, with an area under the curve of 0.713. No significant association was found in studies including patients with prior atrial fibrillation.
Key findings
- Across 27 studies excluding pre-operative atrial fibrillation, pre-operative NLR was higher with POAF (SMD = 0.51; 95% CI: 0.34-0.67; P < .001; I 2 = 94.0%).
- Post-operative NLR was also elevated in POAF patients (SMD = 0.30; 95% CI: 0.13-0.47; P < .001; I 2 = 70.7%).
- In 4 studies including patients with prior atrial fibrillation, NLR was not significantly associated with POAF (SMD = 0.04; P = .21).
- Across 12 diagnostic studies, pooled sensitivity was 0.52, specificity 0.71, and AUC 0.713.
Why it matters
NLR is a readily measured inflammatory marker, and its association with new-onset POAF suggests it may contribute to risk assessment after cardiac surgery. However, the diagnostic results indicate only moderate accuracy, and the findings differ when patients with prior atrial fibrillation are included. These distinctions matter when interpreting NLR evidence and evaluating its potential role alongside other clinical information.
What to keep in mind
The pre-operative association showed substantial heterogeneity (I 2 = 94.0%), and diagnostic accuracy was moderate. The abstract also notes that surgical type should be accounted for when evaluating NLR.