The platelet-to-lymphocyte ratio as a predictor of all-cause mortality in patients with coronary artery disease undergoing elective percutaneous coronary intervention and stent implantation

BACKGROUND: There is no data regarding the association between the platelet-to-lymphocyte ratio (PLR) and long-term mortality in patients with stable coronary artery disease (SCAD). The aim of this study is to evaluate the utility of the pre-procedural PLR for predicting long-term, all-cause mortality in patients with SCAD undergoing percutaneous coronary intervention (PCI) and stent implantation. METHODS: We analyzed a total of 2959 consecutive patients with SCAD who underwent PCI (balloon angioplasty followed by stent implantation or direct stenting) between July 2006 and December 2011 at our institution. The patients were stratified into tertiles according to their admission PLR. The association between the PLR value and the outcomes was assessed using Cox proportional regression analysis after adjusting for clinical angiographic and laboratory data. RESULTS: During median follow-up of 1124 days, mortality was highest in patients with PLR within the 3rd tertile as compared to the 2nd and the 1st tertile (11.0% vs 8.7% vs. 9.6%, respectively, p = 0.03). PLR remained associated with mortality in multivariable analysis including clinical variables, ejection fraction and angiographic parameters HR (per 10 units increase) = 1.02 [95%CI,1.01 ÷ 1.04, p = 0.006]. After adjustment for the eGFR and hemoglobin levels, PLR was however no longer significantly associated with mortality. CONCLUSION: PLR has potential predictive value in patients with SCAD, which has not been reported previously, but statistical significance disappears after adjusting for estimated glomerular filtration rate (eGFR) and hemoglobin levels as a potential confounding variable.