Production of erythropoietin in anemia of various etiology in the elderly

Anemia is a syndrome that often occurs in the elderly and is associated with a poor prognosis. The etiological structure of anemia in the elderly (AE) is diverse. One of the most important pathogenetic mechanisms for the development of anemia of various etiologies is inadequate production of erythropoietin (EPO). Objective: to determine the prevalence of anemia of various etiologies and the adequacy of EPO production in response to anemia among elderly patients. Material and methods. A group of 210 patients, the average age was 77.54 ± 8.47 years. The exclusion criteria – malignant neoplasm or oncohematological disease. Etiological factors of AE were defined as iron deficiency (IDA), B12, folic acid, inflammation (ACD), chronic kidney disease (CKD) and their combinations. The adequacy of EPO production was assessed by the ratio of the logarithm of the determined EPO value to the logarithm of the expected EPO value (0/P lg EPO) obtained for the reference group of patients and using covariance analysis. Results. AE has one cause of development only in 35.2% of cases, in the rest it is a combination of factors. The etiologic structure of AE depending on the leading pathogenetic mechanism: IDA — 9.5%, IDA with CKD — 27%, CKD with GFR less than 60 ml/min/1.73 m2 — 13.8%, CKD with GFR less than 30 ml/min/1.73 m2 —7.6%, B 12 deficiency — 9%, ACD — 14.8%, unexplained anemia of the elderly (UAE) —18%. Inadequate EPO production was observed in the groups of patients with IDA with CKD, CKD, ACD, and UAE; in the groups with IDA and B12-deficient anemia, EPO production was adequate. Conclusions. The prevalence of UAE depends on the selection criteria. Approximately 2/3 of AE cases are polyetiologic. Due to the polyetiology of AE, it is difficult to accurately divide elderly patients by the etiologic sign of anemia. The cause of inadequate EPO production in AE is CKD and inflammation. Inadequate EPO production is observed already with a decrease in GFR to less than 60 ml/min/1.73 m2.