Eosinophil count predicts mortality following percutaneous coronary intervention

IntroductionSeveral inflammatory markers have been shown to be independent predictors for both the development of clinically significant atherosclerosis and for adverse outcome in patients with symptomatic coronary artery disease (CAD). We investigated the prognostic role of eosinophil count in low to intermediate risk patients with CAD.MethodsWe studied 909 patients admitted for elective or urgent percutaneous coronary intervention (PCI) from April 2002 to December 2004, and measured pre-procedural total and differential white blood cell (WBC) counts. Inter-tertile WBC differences in short (6 months) and long term (up to 74 months) mortality were analysed after adjusting for differences in baseline characteristics.ResultsOver a median period of 54 months (inter-quartile range 47–65), a total of 138 deaths (15.2%) occurred, of which 24 were in the first 6 months of follow-up. Cox regression analysis showed that high pre-procedural eosinophil count (top tertile) was associated with improved outcome within the first 6 months (OR = 0.23 [0.06–0.84]; p = 0.03) but after this period there was an increased risk of mortality (OR = 2.21, [1.26–3.88]; p = 0.006).ConclusionsEosinophil count is a novel biomarker for risk stratification of CAD patients, which was associated initially with reduced mortality, but after 6 months with increased mortality.