Platelet to lymphocyte ratio is associated with the severity of coronary artery disease and clinical outcomes of percutaneous coronary intervention in the Chinese Han population

The aim of the present study was to evaluate whether the ratio of the absolute number of platelets to the number of lymphocytes (PLR) correlates with the severity of coronary artery disease (CAD) and major adverse cardiovascular disease (CVD) events in Chinese patients with CAD. PLR was calculated as follows: PLR=platelet count/lymphocyte count, using the complete blood counts of 854 Chinese Han subjects. CAD severity was determined using angiographic evidence by cardiologists unaware of the study aims. The association between PLR and CAD severity was analyzed by logistic regression. Clinical endpoints were evaluated during a median follow-up period of 42 months. The association between PLR and CVD events was assessed using Cox regression models. Patients with PLR>171 exhibited more severe coronary artery stenosis [odds ratio, 2.393; 95% confidence intervals (CI), 1.394-4.108; P=0.002] and worse prognoses, with a higher rate of major adverse CVD events during five years of follow-up (hazard ratio, 1.982; 95% CI, 1.329-2.957; P=0.001). A Kaplan-Meier curve demonstrated that the CVD event rate of 34.27% in patients with PLR>171 was significantly higher than that in patients with PLR<100 (P<0.001). These findings suggest that PLR is independently associated with CAD severity and long-term major adverse CVD events; therefore, high PLR may predict poor prognosis of CAD in the Chinese Han population.