Usefulness of neutrophil-to-lymphocyte ratio for predicting acute pericarditis outcomes.

Background: In daily practice, C-reactive protein (CRP) may be used to predict recurrence and treatment response in patients with acute pericarditis; however, the predictive role of CRP might be insufficient for clinical prediction in some patients. In this study, we aimed to investigate the relationship between neutrophil-to-lymphocyte ratio (NLR) and the composite endpoint of pericarditis recurrence and/or tamponade within 1 year in patients with acute pericarditis.

Methods: A total of 104 patients diagnosed with acute idiopathic pericarditis (mean age 42.8 ± 15.2 years, 55.8% male) were included in the study. Physical examination findings of these patients, electrocardiography, echocardiography, chest X-ray and laboratory findings were evaluated and analysed. During the 1-year follow-up, the composite of cardiac tamponade and/or pericarditis recurrence was investigated as the primary endpoint of the study.

Results: Compared to the group without the composite outcome, the group with the composite outcome had significantly higher rates of moderate and severe pericardial effusion ( < 0.01) and higher white blood cell (WBC) count (p:0.001), platelet count ( = 0.003), NLR (2.14 (1.49-3.02) vs 6.60 (5.50-8.68);  < 0.001) and high-sensitivity C-reactive protein (hs-CRP) (8.01 (5.1-24.5 vs 69.5 (40.8-128); p:0.001). Higher hs-CRP ( < 0.001), WBC (p:0.001), NLR ( < 0.001) and platelets (p:0.02) were associated with pericarditis recurrence. NLR and hs-CRP were independently associated with the composite endpoint ( < 0.001 and  < 0.001, respectively).

Conclusion: NLR and hs-CRP were found to be independent predictors for the composite endpoint of tamponade and/or recurrence in acute pericarditis patients during the 1-year follow-up. Similar to hs-CRP, NLR may also be used for risk assessment in patients with idiopathic pericarditis.