Prognostic implications of chronic kidney disease and anemia after percutaneous coronary intervention in acute myocardial infarction patients

Anemia is a common complication of chronic kidney disease (CKD), and a few studies suggest that both CKD and anemia have a marked impact on the prognosis of patients with cardiovascular disease. We retrospectively analyzed the prevalence of CKD and anemia in 312 patients with acute myocardial infarction (AMI). The patients were divided into four groups according to the presence of CKD and anemia. Chronic kidney disease was defined as estimated glomerular filtration rate < 60 ml/min/1.73 m(2), and anemia was defined according to the World Health Organization definition. Of 312 AMI patients, 166 (53.2%) had CKD and 87 (27.8%) had anemia. A powerful relationship was observed between both CKD and anemia and major adverse cardiac and cerebrovascular events (MACCE) or death by any cause. After adjustment for comorbidities, the hazard ratio (HR) for MACCE was significantly higher in the anemia-only group (HR 5.42, 95% confidence interval (CI) 1.38-21.27, P = 0.015), the CKD-only group (HR 6.4, 95% CI 2.09-19.58, P = 0.001), and the CKD and anemia group (HR 11.61, 95% CI 3.65-36.89, P < 0.001). With respect to death by any cause, the HR was significantly higher in the CKD-only group (HR 2.68, 95% CI 1.02-7.02, P = 0.045) and the CKD and anemia group (HR 4.40, 95% CI 1.56-12.43, P = 0.005). One-half of the patients with AMI had CKD as well. Furthermore, when anemia coexisted with CKD, these conditions had a multiplicative amplification effect on the risk of MACCE and death by any cause in patients with AMI.