The potential value of the neutrophil to lymphocyte ratio for early differential diagnosis and prognosis assessment in patients with aortic dissection

Objectives: The aim of the study was to assess the diagnostic performance and clinical utility of the neutrophil to lymphocyte ratio (NLR) in patients with suspected aortic dissection (AD) and investigate its role in predicting in-hospital mortality in AD.

Methods: NLR values were calculated and compared in 467 consecutive patients with initially suspected AD. A receiver operating characteristic (ROC) curve analysis with the area under the curve (AUC) was used to evaluate the discriminative accuracy and predictive capability of the NLR for AD. Clinical utility was determined by decision curve analysis (DCA). The association between NLR and in-hospital mortality was investigated by logistic regression analyses in patients diagnosed with AD.

Results: The NLR was significantly elevated in patients with AD, and the optimal cut-off point for the NLR to distinguish AD from other acute chest pain diseases was 5.67 [AUC (95% CI): 0.877 (0.844-0.905)]. We recommended an NLR of 2.43 as the appropriate cut-off point with 96.9% sensitivity and a negative likelihood ratio (LR) of 0.09 to satisfy clinical requirements for diagnosis. DCA showed that the use of NLR had a positive net benefit. The deceased patients with AD had a higher NLR than the discharged patients. Moreover, the NLR was an independent predictor of in-hospital mortality for AD [adjusted odds ratio (OR): 1.084 (1.029-1.142)], and patients with higher NLR values tended to have a higher risk of in-hospital mortality. The optimal cut-off point for the NLR to predict in-hospital mortality was 9.20 [AUC (95% CI): 0.695 (0.619-0.765)].

Conclusions: As an easily available and inexpensive parameter, the NLR could serve as a valuable clinical biomarker for early differential diagnosis and prognosis assessment of AD.