Risk factors for development of the post-COVID syndrome

Aim: to study risk factors of development of the post-COVID syndrome (PCS).Material and methods. 210 patients with a history of new coronavirus infection (COVID-19) (47 men, 163 women aged 18–85 years) were examined by doctors of various specialties. Patients were divided into several groups depending on the presence of PCS, as well as the severity of the disease.Results. The risk factors of the PCS development are moderate and severe course of the pathological process in acute period of COVID-19 disease (p < 0.001). In women, PCS is seen more often than in men (30 / 135 vs. 17 / 28, p < 0 / 001), other risk factors are age over 50 years (p < 0.05), polymorbidity (p < 0.01), treatment with glucocorticoids in acute disease period (76 / 165 vs. 4 / 45, p < 0.001). In cases of mild COVID-19 course, neither age nor polymorbidity increased the risk of PCS development (p > 0.05), however a dysfunction of cellular immunity was significant, specifically the proliferative activity of lymphocytes in response to mitogen: 50.6 ± 10.4 % vs. 54.0 ± 5.1 %, p < 0.05). In cases of severe COVID-19 course, the gender differences and dysfunction of the cellular immune system are not the determinants for the PCS development (p > 0.05), however the age (56.7 ± 13.1 years vs. 42.1 ± 15.4 years, p < 0.01) its linkage to somatic pathology (a cardiovascular disease) besides glucocorticoids threatment (64 / 89 vs. 3 / 9, p < 0.05) are important risk factors for PCS.Conclusions. The main risk factor for PCS development is the moderate and severe course of the pathological process in the acute period of COVID-19 infection, female gender, age over 50 years, polymorbidity, treatment with glucocorticoids in the disease acute period. In case of mild COVID-19 course, neither age nor the polymorbidity increased the risk of PCS development, but the dysfunction of cellular immunity is significant. In case of severe COVID-19, the gender differences and dysfunction of the cellular immune system are not the determinants for the PCS development, however age, concomitant somatic pathology (a cardiovascular disease) and glucocorticoids treatment in acute period are important risk factors for the PCS development. The titer of protective IgG class antibodies to SARS-CoV-2 is not linked to risk of the PCS development.