Red blood cell distribution width as a biomarker of chronic heart failure severity in elderly patients

. Chronic heart failure (CHF) is recognized as one of the most severe cardiovascular diseases with a high mortality rate. Early identification of patients at risk of poor outcomes is critical to optimize treatment. Aim: to conduct comparative analysis of laboratory markers, including the erythrocyte heterogeneity index (RDW) in CHF patients of different functional classes (f.cl.) according to ICD-10 codes. Materials and methods. A  retrospective cross-sectional study with an analysis of  the  electronic laboratory register (JanuaryDecember 2016). 8056 patients who underwent a clinical blood test and added CRP parameters were included. The determination of the patient’s belonging to CHF wascarried out according to the ICD-10 code indicated in the direction for analysis. Identification of CHF patients by f.cl. (NYHA) was carried out according to the ICD-10 codes: code I25.2 (Postponed myocardial infarction) – 1 f. cl.; code I11.0 (Hypertensive disease with predominant heart damage with heart failure) – 2–3 f.cl .; code I50.0 (Congestive heart failure) – 4 f.cl. Results. The proportion of patients with diseases of the circulatory system (code I) was 33.4% (n = 2686), of which 403 CHF patients were selected for the study. Distribution by f.cl. according to the code MKB-10: 1 ph.cl. – 0.83% (n = 67); 2–3 f.c. – 3.84% (n = 309); 4 ph.cl. – 0.33% (n = 27). Significant intergroup differences were obtained between ph.cl. (according to Kruskal–Wallis) for  indicators: hemoglobin (H = 9.741111, p = 0.0077), erythrocytes (H = 7.176770, p = 0.0276), RDW indicator (H = 34.78287, p = 0.0000). There were no statistically significant differences in leukocytes, platelets, ESR, CRP. Conclusions. The presence of anemia in groups of patients with CHF of different f.cl., which often accompanies the disease, has not been confirmed. But statistically significant differences were revealed depending on the severity of f.cl. CHF according to the level of hemoglobin, the number of erythrocytes, and highly significant - according to the RDW indicator. The latter allows us to discuss the role of the RDW index as a possible new laboratory biomarker of CHF severity available for routine clinical practice.