Effect of Baseline Red Blood Cell Distribution Width on Short- and Intermediate-term Mortality of Patients Under Primary Percutaneous Coronary Intervention: A Survival Analysis.

OBJECTIVE: Considering the limited studies specifically evaluating the role of Red blood cell distribution width (RDW) in primary percutaneous coronary intervention (PCI), we aimed to investigate the role of baseline RDW in short- and intermediate-term cardiovascular events in ST-elevation myocardial infarction patients under primary PCI.

METHODS: This is a historical cohort registry analysis of 1161 patients with ST-elevation myocardial infarction under primary PCI. According to inclusion criteria, 838 patients were allocated for analysis. Patients with RDW levels of 13.6% or higher were considered as high RDW group (third tertile). All the individuals were followed up for in-hospital and 6-month mortality along with readmission and composite major adverse cardiac events.

RESULTS: In-hospital deaths occurred in 53 (6.3%) patients and at 6-month follow-up 79 (9.4%) cases of mortality were documented. In-hospital and 6-month mortalities showed a significant trend in favor of high RDW group (13.3% vs. 5.9%, P = 0.003; 19.7% vs. 7.9%, P < 0.001, respectively). Multivariate analysis showed that high RDW was significantly and independently associated with higher rates of 6-month mortality (hazard ratio: 2.909; 95% confidence interval: 1.166-7.257; P = 0.022). RDW was also a significant predictor for 6-month mortality independent of anemia (hazard ratio: 2.811; 95% confidence interval: 1.047-7.551; P = 0.040).

CONCLUSIONS: We found a significant association between high RDW and in-hospital and 6-month mortality as well as the occurrence of major adverse cardiac event. Meanwhile RDW was found to be a significant predictor for 6-month mortality independent of anemia. Thus, it would be beneficial to use RDW as a risk stratification index to identify high risk intent-to-treat patients.