What is the real predictive value of red cell distribution width for the mortality in non-ST elevation acute coronary syndrome?

To the Editor,

I have read the recently published article by Bekler et al. (1) “Relationship between red cell distribution width and long-term mortality in patients with non-ST elevation acute coronary syndrome” entitled with great interest in Anatol J Cardiol 2014 Jun 23. In their study, authors reported that high red cell distribution width (RDW) level on admission is a predictor of long-term mortality in patients with non-ST elevation acute coronary syndrome (NST-ACS). In this paper, I would like to emphasize the possible effects of medical treatment of patient groups on the endpoints of this study. In the present study by Bekler et al. (1), there are no data regarding patient groups’ medications. It is well known that optimal medical therapy reduces the early and long-term mortality in patients with NST-ACS. Based on our previous knowledge and according to the current guideline, it is recommended to use oral beta-blockers, long-term treatment with aspirin, and dual antiplatelet therapy for at least 12 months as well as to use statins and angiotensin-converting enzyme inhibitors (ACEI)/angiotensin-receptor blockers (ARB) to reduce mortality and major adverse cardiovascular events (MACE) in NST-ACS patients (2). Also, it has been reported that dual antiplatelet therapy with ticagrelor significantly reduced the mortality and MACE in NST-ACS patients as opposed to the patients treated with aspirin and clopidogrel (3, 4). Hence, authors should comment on the incidence of patients treated with optimal medical therapy in both high RDW and low RDW groups and compare the groups regarding beta-blockers, ACEI/ARB, statins, dual antiplatelet usage rates, and the type of dual antiplatelet therapy. Because the results of the present study by Bekler et al. (1) may not be due to high RDW level, less medications rates with optimal medical therapy in high RDW level group may be the main reason for higher mortality.

In conclusion, the statistical data of the present study by Bekler et al. (1) may be improved. Authors should report the patients’ medications in both groups. High RDW level may indicate poor prognosis in NST-ACS patients. However, to define its exact role on mortality, conventional medical treatments that are known to reduce the mortality should be considered.