Indices of the peripheral blood cellular immunity elderly in the patients with malnutrition

The complex dynamic process of immunosenescence is characterized by significant changes in compartments and functions of both innate and acquired defense of the organism associated with continuous depletion of immune cells. The imbalance resulting from insufficient nutrient intake, malnutrition, affects the pathogenesis of chronic diseases. The aim of the study: to determine the subpopulations of CD4⁺ and CD8⁺T lymphocytes, B cells, naive and memory cells in malnutrition. Total number of lymphocytes, cytotoxic and T helper subsets, percentage of CD45RA⁺ naive and CD45RO⁺ memory cells, neutrophils and monocytes were determined in peripheral blood of healthy individuals < 60 years old (20 people) and older persons (22 people), and in patients with moderate (22 people) and severe malnutrition (20 people). Positive correlations were established for patients with malnutrition between the parameters of standard evaluation scales and bioimpedance analysis, namely, lean mass (r = 0.654, p < 0.001), active cellular (r = 0.875, p < 0.001) and muscle mass (r = 0.679, p < 0.001). In elderly individuals, a significantly increased percentage of total CD3⁺ cells of cytotoxic T lymphocytes and neutrophils was observed, and, conversely, the number of B lymphocytes and NK cells was decreased (p < 0.05). Moreover, the number of naive cells (CD45RA) was decreased and the number of memory cells (CD45R0) increased. A negative correlation was established between the presence of malnutrition in patients and the number of CD45RA⁺ from CD3⁺ cells and their CD4⁺ subpopulation (rCD3⁺ = -0.692, rCD4⁺ = -0.595). On the contrary, a positive correlation was revealed with levels of CD45R0⁺T lymphocytes (rCD3⁺ = 0.714, rCD4⁺ = 0.718, respectively). With increased severity of malnutrition, the neutrophil-to-lymphocyte ratio were found to be significantly decreased (p < 0.05). In elderly people, compared to young persons, we have found an increased number of neutrophils, cytotoxic T lymphocytes, and, conversely, lower numbers of B lymphocytes and NK cells (p < 0.05). In elderly patients with malnutrition, compared to young people, the number of naive lymphocytes and CD8⁺T memory cells is decreased, and the number of CD4⁺T memory cells is significantly higher. The indexes of systemic inflammation in elderly patients correlate with degree of malnutrition.