COPD, 11:475–476, 2014 ISSN: 1541-2555 print / 1541-2563 online Copyright © Informa Healthcare USA, Inc. DOI: 10.3109/15412555.2013.813449
LETTER TO THE EDITOR
Red Cell Distribution Width: A Novel and Simple Predictor of Mortality in Chronic Obstructive Pulmonary Disease Sevket Balta,1 MD, Mehmet Aydogan,2 MD, Sait Demirkol,1 MD, Assistant Professor of Cardiology, Mustafa Cakar,3 MD, Emin Ozgur Akgul,4 MD, Associate Professor of Cardiology, Hakan Sarlak,3 MD 1
Department of Cardiology, Gulhane Medical Academy Ankara/Turkey
2
Department of Pulmonary Medicine, Gulhane Medical Academy Ankara/Turkey
3
Department of Internal Medicine, Gulhane Medical Academy Ankara/Turkey
4
Department of Clinical Biochemistry, Gulhane Medical Academy Ankara/Turkey
Correspondence to: Dr Sevket Balta, Department of Cardiology, Gulhane School of Medicine, Tevfik Saglam St., 06018 Etlik-Ankara, Turkey, tel: +90-312-3044281, fax: +90-312-3044250, email: [email protected]
Dear Editor, We have read with great interest the recently published article entitled, ‘‘Red Blood Cell Distribution (RDW) and Survival in Patients with Chronic Obstructive Pulmonary Disease (COPD),’’ by Seyhan and coworkers (1). In this very well presented article the authors aimed to evaluate whether RDW is effective as a prognostic marker in a population with COPD. They demonstrated that elevated RDW levels in patients with COPD are associated with an increased risk for mortality. They suggested that an elevated RDW may be an indicator of underlying inflammation and oxidative stress in COPD and it could be a useful, inexpensive, and CVD associated prognostic factor in COPD patients. COPD is one of the most important causes of morbidity and mortality in the world, and is characterized by irreversible airway obstruction due to narrowing of small airways, bronchiolitis, and destruction of the lung parenchyma (2). COPD is complicated by frequent and recurrent acute exacerbations which cause unfavorable results for patients and healthcare providers, such as a negative impact on health-related quality of life, pulmonary function, utilization of healthcare resources and survival. The increased level of inflammatory markers in serum play important roles in the pathogenesis of COPD (3). Red cell distribution width is a measure of the variability in the size of circulating red blood cells and is a part of the complete blood count panel. It is frequently used as a technique for the differential diagnosis of anemia and could be elevated in any condition where reticulocytes are released into circulation. RDW is a standard laboratory parameter that indicates variation in red blood cell size on a standard hemogram and is usually used in assessing blood diseases. It is associated with mortality in the general population. RDW has recently been demonstrated to highly correlate with short- and long-term outcomes in different clinical settings (4). However, conditions in the differential diagnosis of anemia might affect RDW, and so this parameter might be changed in the presence of any abnormalities such as coronary artery disease, hypertension, diabetes mellitus, thyroid disease, renal or hepatic dysfunction, inflammatory diseases, the use of any medications, and is related to nutritional deficiency and ethnicity. Additionally, not only RDW, but also mean platelet volume (5), neutrophil lymphocyte ratio (6), platelet distribution width, uric acid and a gamma-glutamyltransferase are easy methods to assess trauma patients. These markers might be useful in clinical practice. Finally, because the authors evaluated trauma patients retrospectively in the present study, the authors might not accurately define how much time they specified on measuring RDW levels due to delayed blood sampling that can cause abnormal results in RDW measurements. 475
476
Balta et al.
In conclusion, we believe that the findings obtained from the present study will lead to further large-scale prospective studies evaluating the relationship between RDW and COPD patients. However, RDW alone without other inflammatory markers may not give proper information to researchers about the inflammatory status and prognostic indication of patients. So, from that point of view we think that it should be evaluated in association with other serum inflammatory markers.
Declaration of Interest Statement There is no conflict of interest.
References 1. Seyhan EC, Ozgül MA, Tutar N, Omür I, Uysal A, Altın S. Red Blood Cell Distribution and Survival in Patients with Chronic Obstructive Pulmonary Disease. COPD 2013 Mar 28;1–9.
2. Lyngsø AM, Gottlieb V, Backer V, Nybo B, Ostergaard MS, Jørgensen HL, et al. Early Detection of COPD in Primary Care: The Copenhagen COPD Screening Project. COPD 2013 Apr; 10(2):208–15. 3. Zhang L, Cheng Z, Liu W, Wu K. Expression of Interleukin (IL)-10, IL-17A and IL-22 in Serum and Sputum of Stable Chronic Obstructive Pulmonary Disease Patients. COPD. 2013 Mar 28; 2013; 10(4):459–65. 4. Balta S, Demirkol S, Aydogan M, Unlu M. Red cell distribution width is a predictor of mortality in patients undergoing coronary artery bypass surgery. Eur J Cardiothorac Surg 2013 Feb 21; 2013; 44(2):396–7. 5. Demirkol S, Balta S, Unlu M, Yuksel UC, Celik T, Arslan Z, et al. Evaluation of the mean platelet volume in patients with cardiac syndrome X. Clinics (São Paulo, Brazil). 2012 Sep; 67(9):1019–22. 6. Demirkol S, Balta S, Unlu M, Arslan Z, Cakar M, Kucuk U, et al. Neutrophils/Lymphocytes Ratio in Patients With Cardiac Syndrome X and Its Association With Carotid Intima-Media Thickness. Clin Appl Thromb Hemost 2012 Nov 26;
Copyright © 2014 Informa Healthcare USA, Inc
Copyright of COPD: Journal of Chronic Obstructive Pulmonary Disease is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
LETTER TO THE EDITOR
Red Cell Distribution Width: A Novel and Simple Predictor of Mortality in Chronic Obstructive Pulmonary Disease Sevket Balta,1 MD, Mehmet Aydogan,2 MD, Sait Demirkol,1 MD, Assistant Professor of Cardiology, Mustafa Cakar,3 MD, Emin Ozgur Akgul,4 MD, Associate Professor of Cardiology, Hakan Sarlak,3 MD 1
Department of Cardiology, Gulhane Medical Academy Ankara/Turkey
2
Department of Pulmonary Medicine, Gulhane Medical Academy Ankara/Turkey
3
Department of Internal Medicine, Gulhane Medical Academy Ankara/Turkey
4
Department of Clinical Biochemistry, Gulhane Medical Academy Ankara/Turkey
Correspondence to: Dr Sevket Balta, Department of Cardiology, Gulhane School of Medicine, Tevfik Saglam St., 06018 Etlik-Ankara, Turkey, tel: +90-312-3044281, fax: +90-312-3044250, email: [email protected]
Dear Editor, We have read with great interest the recently published article entitled, ‘‘Red Blood Cell Distribution (RDW) and Survival in Patients with Chronic Obstructive Pulmonary Disease (COPD),’’ by Seyhan and coworkers (1). In this very well presented article the authors aimed to evaluate whether RDW is effective as a prognostic marker in a population with COPD. They demonstrated that elevated RDW levels in patients with COPD are associated with an increased risk for mortality. They suggested that an elevated RDW may be an indicator of underlying inflammation and oxidative stress in COPD and it could be a useful, inexpensive, and CVD associated prognostic factor in COPD patients. COPD is one of the most important causes of morbidity and mortality in the world, and is characterized by irreversible airway obstruction due to narrowing of small airways, bronchiolitis, and destruction of the lung parenchyma (2). COPD is complicated by frequent and recurrent acute exacerbations which cause unfavorable results for patients and healthcare providers, such as a negative impact on health-related quality of life, pulmonary function, utilization of healthcare resources and survival. The increased level of inflammatory markers in serum play important roles in the pathogenesis of COPD (3). Red cell distribution width is a measure of the variability in the size of circulating red blood cells and is a part of the complete blood count panel. It is frequently used as a technique for the differential diagnosis of anemia and could be elevated in any condition where reticulocytes are released into circulation. RDW is a standard laboratory parameter that indicates variation in red blood cell size on a standard hemogram and is usually used in assessing blood diseases. It is associated with mortality in the general population. RDW has recently been demonstrated to highly correlate with short- and long-term outcomes in different clinical settings (4). However, conditions in the differential diagnosis of anemia might affect RDW, and so this parameter might be changed in the presence of any abnormalities such as coronary artery disease, hypertension, diabetes mellitus, thyroid disease, renal or hepatic dysfunction, inflammatory diseases, the use of any medications, and is related to nutritional deficiency and ethnicity. Additionally, not only RDW, but also mean platelet volume (5), neutrophil lymphocyte ratio (6), platelet distribution width, uric acid and a gamma-glutamyltransferase are easy methods to assess trauma patients. These markers might be useful in clinical practice. Finally, because the authors evaluated trauma patients retrospectively in the present study, the authors might not accurately define how much time they specified on measuring RDW levels due to delayed blood sampling that can cause abnormal results in RDW measurements. 475
476
Balta et al.
In conclusion, we believe that the findings obtained from the present study will lead to further large-scale prospective studies evaluating the relationship between RDW and COPD patients. However, RDW alone without other inflammatory markers may not give proper information to researchers about the inflammatory status and prognostic indication of patients. So, from that point of view we think that it should be evaluated in association with other serum inflammatory markers.
Declaration of Interest Statement There is no conflict of interest.
References 1. Seyhan EC, Ozgül MA, Tutar N, Omür I, Uysal A, Altın S. Red Blood Cell Distribution and Survival in Patients with Chronic Obstructive Pulmonary Disease. COPD 2013 Mar 28;1–9.
2. Lyngsø AM, Gottlieb V, Backer V, Nybo B, Ostergaard MS, Jørgensen HL, et al. Early Detection of COPD in Primary Care: The Copenhagen COPD Screening Project. COPD 2013 Apr; 10(2):208–15. 3. Zhang L, Cheng Z, Liu W, Wu K. Expression of Interleukin (IL)-10, IL-17A and IL-22 in Serum and Sputum of Stable Chronic Obstructive Pulmonary Disease Patients. COPD. 2013 Mar 28; 2013; 10(4):459–65. 4. Balta S, Demirkol S, Aydogan M, Unlu M. Red cell distribution width is a predictor of mortality in patients undergoing coronary artery bypass surgery. Eur J Cardiothorac Surg 2013 Feb 21; 2013; 44(2):396–7. 5. Demirkol S, Balta S, Unlu M, Yuksel UC, Celik T, Arslan Z, et al. Evaluation of the mean platelet volume in patients with cardiac syndrome X. Clinics (São Paulo, Brazil). 2012 Sep; 67(9):1019–22. 6. Demirkol S, Balta S, Unlu M, Arslan Z, Cakar M, Kucuk U, et al. Neutrophils/Lymphocytes Ratio in Patients With Cardiac Syndrome X and Its Association With Carotid Intima-Media Thickness. Clin Appl Thromb Hemost 2012 Nov 26;
Copyright © 2014 Informa Healthcare USA, Inc
Copyright of COPD: Journal of Chronic Obstructive Pulmonary Disease is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
