Erratum: Anemia of Chronic Disease in Chronic Obstructive Pulmonary Disease: A Case-Control Study of Cardiopulmonary Exercise Responses
datasetposted on 25.07.2017 by Boutou A.K., Stanopoulos I., Pitsiou G.G., Kontakiotis T., Kyriazis G., Sichletidis L., Argyropoulou P.
Datasets usually provide raw data for analysis. This raw data often comes in spreadsheet form, but can be any collection of data, on which analysis can be performed.
Background: Anemia may be present in patients with chronic obstructive pulmonary disease (COPD) and further impair their functional capacity. Objectives: This study investigated the prevalence of anemia of chronic disease (ACD) in COPD patients and its impact on dyspnea and exercise capacity, utilizing cardiopulmonary exercise testing (CPET). Methods: ACD prevalence was assessed in 283 consecutive patients with stable COPD (263 males, 60 females; age 60.31 ± 5.34 years; percent forced expiratory volume in 1 s 46.94 ± 6.12). ACD diagnosis was based on a combination of clinical and laboratory parameters [hemoglobin (Hb) <13 g/dl for males, <12 g/dl for females; ferritin >30 ng/ml; total iron-binding capacity <250 µg/dl, and transferrin saturation rate between 15 and 50%]. Twenty-seven patients who were identified with ACD (cases) and 27 matched nonanemic patients (controls) completed maximal CPET, and data were compared between the groups. Results: ACD was diagnosed in 29 patients, which represents a prevalence of 10.24%; the severity of anemia was generally mild (mean Hb: 12.19 ± 0.66 g/dl). Patients with ACD had a higher Medical Research Council dyspnea score compared to controls (2.78 ± 0.44 vs. 2.07 ± 0.55; p <0.001) and lower peak O2 uptake (VO2) (59.54 ± 17.17 vs. 71.26 ± 11.85% predicted; p <0.05), peak work rate (54.94 ± 21.42 vs. 68.72 ± 20.81% predicted; p <0.05) and peak VO2/heart rate (69.07 ± 17.26 vs. 82.04 ± 18.22% predicted; p <0.05). There was also a trend for a lower anaerobic threshold (48.48 ± 15.16 vs. 55.42 ± 9.99% predicted; p = 0.062). No exercise parameter indicative of respiratory limitation differed between the groups. Conclusions: ACD occurs in approximately 10% of stable COPD patients and has a negative impact on dyspnea and circulatory efficiency during exercise.