COPD: performance of red cell distribution width in predicting the occurrence of frequent exacerbations

<bold>Introduction:</bold> Red Cell Distribution Width (RDW) is a routine laboratory parameter indicating the variability in the size of circulating erythrocytes. It is intricately linked to the prognosis of several respiratory diseases, including the occurrence of exacerbations in Chronic Obstructive Pulmonary Disease (COPD). <bold>Aims:</bold> Evaluate the performance of RDW in predicting the occurrence of frequent exacerbations in COPD. <bold>Methods:</bold> This prospective study included patients followed at the Pneumology Department of Charles Nicolle Hospital in Tunis with confirmed COPD over a 4-year period from December 2017 to December 2021. The patients were followed for 12 months. Frequent exacerbations were defined as the occurrence of 2 or more exacerbations per year. High RDW was defined as a level >13.5%. <bold>Results:</bold> In this study, 200 patients were enrolled. The mean age was 64.02±12 years. The sex ratio was 8.09. Smoking was observed in 95.5% of patients. The mean exacerbations/year were higher in patients with RDW > 13.5% (2.83 vs 1.23; p<0.001). Similarly, frequent exacerbations were observed in 75 patients (37.5%), of whom 57 had RDW > 13.5% (p<0.001). The AUC for RDW to predict frequent exacerbations was 0.85 ([0.80-0.910]; 95% CI, p<0.001). The optimal RDW cutoff was 13.7%, with a sensitivity and specificity of 80%. <bold>Conclusions:</bold> RDW, a basic marker for inflammation, seems to be a practical tool in predicting frequent exacerbations in COPD, especially when the level is at 13.7%.