Objective: Coronary heart disease is the most common cause of death in most countries and also in Iran. Among novel prognostic markers suggested in recent studies for coronary heart disease, red blood cell distribution width (RDW) has been found to be associated with poor prognosis. Therefore, we aimed to evaluate the relationship between RDW and 6-month mortality and cardiovascular events after the initial attack of myocardial infarction (MI).
Methods: Medical records of 642 patients with MI were investigated for basic and clinical characteristics, as well as patients' first hemoglobin, RDW, and mean corpuscular volume at the time of admission. Then based on patients' time of hospitalization, they were followed up by telephone for readmission and mortality 6 months later.
Results: Mean ± SD age of patients was 62.7 ± 12.7 years. In 6-month telephone follow-up, 443 patients (69%) had readmission. Six-month mortality occurred in 70 patients (10.9%). Patients with RDW level of 14.6% and higher were significantly older (P < 0.001). Three percent of patients with low RDW and 14.8% in high RDW group had renal failure (P < 0.001). Six-month mortality was observed in 24.3% of patients with high RDW and 7.9% of those with low RDW (P < 0.001). In multivariate logistic regression analysis, RDW (odds ratio: 1.98, 95% confidence interval: 1.06-3.68, P = 0.03), age, and ejection fraction were significant independent prognostic factors for mortality.
Conclusions: Six-month mortality was significantly higher in patients with MI with high RDW. Thus given that RDW is an inexpensive and available laboratory test, it could be used for mortality risk assessment and follow up the patients for stricter control of other modifiable risk factors.