Assessing Risk for Stroke in Patients with Atrial Fibrillation

David Green, MD, PhD reviewing Saliba W et al. J Thromb Haemost 2015 Nov. Shantsila E and Lip GYH. J Thromb Haemost 2015 Nov.

Although the CHA2DS2-VASc score (heart failure, hypertension, age ≥75, diabetes, stroke or TIA, vascular disease, gender) is the most widely used method for assessing stroke risk in patients with atrial fibrillation (AF), its predictive value is modest. The neutrophil lymphocyte ratio (NLR) is another predictor of adverse events in patients with various cardiovascular diseases.

To examine the value of the NLR in predicting stroke risk, investigators used the electronic medical registry of a large healthcare provider to analyze clinical data, including complete blood counts, on 32,912 AF patients without prior stroke, transient ischemic attack, or anticoagulant use.

During a 1-year period, 981 patients had a stroke (incidence rate, 3.17/100 person-years). The risk for stroke increased with higher NLR quartiles, rising from a hazard ratio of 1.11 for the lowest quartile to 1.56 for the highest quartile (P<0.001 for trend). The NLR was positively correlated with the CHA2DS2-VASc score (P<0.001), and adding the NLR to that score significantly improved its predictive ability (P=0.037). The association of the NLR with stroke was not affected by anemia, baseline comorbidities, or medication use.

Comment

Atherosclerosis and AF are accompanied by an inflammatory process that elevates neutrophil levels and depresses lymphocyte counts, thereby increasing the NLR. The NLR is a simple and readily available measure that can be combined with the CHA2DS2-VASc score to improve risk stratification for stroke in patients with AF.

CITATION(S):

  1. Saliba W et al. Neutrophil to lymphocyte ratio and risk of a first episode of stroke in patients with atrial
    fibrillation: A cohort study. J Thromb Haemost ; :. ( http://dx.doi.org/10.1111/jth.13006 )
  2.  Shantsila E and Lip GYH.Stroke in atrial fibrillation and improving the identification of ‘high­risk’ patients: The
    crossroads of immunity and thrombosis. J Thromb Haemost ; :. ( http://dx.doi.org/10.1111/jth.13121 )