The role of red cell distribution width as a predictor of bronchopulmonary dysplasia in preterm infants

Correspondence (İletişim): Pelin Doğan, M.D. Bursa Yuksek Ihtisas Egitim ve Arastirma Hastanesi, Yildirim, 16120 Bursa, Turkey Phone (Telefon): +90 505 316 42 68 E-mail (E-posta): pelin_akbas@yahoo.com Submitted Date (Başvuru Tarihi): 09.10. 2019 Accepted Date (Kabul Tarihi): 04.11. 2019 Copyright 2019 Haydarpaşa Numune Medical Journal OPEN ACCESS This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/). 358 Doğan, The Role of Red Cell Distribution Width as a Predictor of Bronchopulmonary Dysplasia in Preterm Infants / doi: 10.14744/hnhj.2019. 53824 struction may alter the size of the erythrocytes, causing a change in RDW. The systemic inflammatory response also affects erythrocyte destruction and erythropoiesis, and increased RDW values may indicate an underlying inflammatory reaction [7]. RDW is a marker that has been used in the meta-analysis for the follow-up of cardiac, renal, and pancreatic pathologies, especially in adults, and for the follow-up critical patients and predicting mortality [7–10]. In recent years, there are limited studies on the role of RDW in the follow-up of various diseases, such as patent ductus arteriosus (PDA), pulmonary hypertension and mortality in newborns with RDW [6, 11, 12]. The present study aims to investigate the role of RDW value in predicting BPD in preterm infants at birth. Materials and Methods Cases that were hospitalized at ≤32 gestational weeks and treated for six months in the Neonatal Intensive Care Unit (NICU) of the University of Health Sciences, Bursa Yuksek Ihtisas Teaching Hospital, were included in this retrospective cohort study. The study group was divided into two groups as preterm infants who developed BPD or the control group that did not develop BPD during the follow-up period in NICU. Depending on the gestational age at birth, the definition of BPD was made as postmenstrual (PM) when BPD occurs at 36th weeks for those with gestational week of <32 weeks, and BPD requiring ≥21 O2. for those with gestational age of ≥32 weeks when BPD emerges at postnatal 28th day or earlier and persists at discharge time [13, 14]. Patients with moderate/severe maternal anemia, pregnant patients using drugs affecting fetal hematopoietic system, patients with a history of familial hematological disease, such as thalassemia, major congenital anemia, hydrops fetalis, patients undergoing intrauterine transfusion, patients whose maternal and neonatal data could not be reached and cases exited during follow-up period were excluded from this study. Data concerning maternal medical history, antenatal steroid use, early membrane rupture and/ or chorioamnionitis, maternal preeclampsia or infection, neonatal features including gestational age, birth weight, sex, mode of delivery, Apgar scores at 1st and 5th minutes, duration of invasive mechanical or non-invasive ventilation, oxygen use and hospitalization were recorded. Within the first three hours after birth, 2 ml samples of blood were drawn from peripheral veins of all patients included in this study and placed in the tube containing tripotassium ethylenediaminetetraacetic acid within the first three hours after birth, and blood count was performed within one hour after blood collection. Hematological parameters were defined by the Sysmex-XT-2000i blood counter (Sysmex, Kobe, Japan). Complete blood count parameters, including RDW of the blood samples of all patients, were recorded. BPD and control groups were compared concerning RDW and other complete blood count parameters. Statistical Analysis Statistical analysis was performed using IBM SPSS 20.0 (SPSS Inc., Chicago, IL, USA) statistical package program. The fitness to normal distribution was evaluated by the Kolmogorov-Smirnov Test. Numerical variables were given as mean +/standard deviation and median (25th percentile to 75th percentile). Categorical variables were expressed as numbers and percentages. Differences between the groups were evaluated with the Student t-test and one-way analysis of variance (ANOVA). Mann-Whitney U Test was used for numerical variables with nonnormal distribution. Fisher's Exact and chi-square analyses were used for categorical variables. Logistic regression analysis was performed to investigate the relationship between RDW and BPD and factors affecting BPD were added to the model. ROC analysis was performed to evaluate the predictive power of different values. P-value of <0.05 was considered statistically significant.