Objective:To investigate the prognostic significance of anemia in elderly patients with stable coronary artery disease treated by percutaneous coronary intervention(PCI).Methods:In this retrospective cohort study, 180 patients with stable coronary artery disease aged ≥60 years undergone percutaneous coronary intervention and with complete clinical data, admitted to Nanjing Meishan Hospital between June 2016 and December 2017, were selected.Baseline clinical data of the patients were collected, including hemoglobin, C-reactive protein, lipids, fasting glucose, glycated hemoglobin, blood creatinine, and left ventricular ejection fraction on cardiac color ultrasound.The endpoints of the follow-up included major adverse cardiac events(MACE), such as all-cause death, non-fatal myocardial infarction, and non-fatal stroke.According to the hemoglobin level, participants were divided into an anemia group(n=32)and a non-anemia group(n=148). Clinical data of the two groups were compared, and the Kaplan-Meier method and multivariate analysis with the Cox regression method were used to evaluate the effect of anemia on the occurrence of MACE in elderly patients with stable coronary artery disease treated by PCI.Results:The median duration of the follow-up of the 180 patients was 702.5 days and MACE occurred in 27(15.0%). Compared with the non-anemia group, the anemia group had a higher age, C-reactive protein level and MACE ratio, lower levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol and the glomerular filtration rate, and higher proportions of patients with smoking history and patients with dyslipidemia( P<0.05). Kaplan-Meier curves suggested that the incidence of MACE in the anemia group was higher than that in the non-anemia group[37.5%(12/32) vs.10.1%(15/148), P<0.05]. Multivariate analysis with the Cox regression method showed that the risk of MACE in the anemia group was 2.91 times higher than that in the non-anemia group( HR=2.91, 95% CI: 1.13-7.48, P<0.05). Conclusions:Anemia is an independent predictor of MACE in elderly patients with stable coronary artery disease after PCI.