Comparative analysis of Covid-19 course and post-covid syndrome caused by early strains and omicron strain in patients with rheumatic diseases

Abstract

Aim. To conduct a comparative analysis of the course of a new coronavirus infection (NCI) and post-Covid syndrome (PCS) caused by the Omicron strain and earlier strains in patients with rheumatic diseases (RD).Materials and methods. 271 patients with NCI were included in the study. For a comparative analysis of the course of Covid-19 and PCS, two periods were defined: the first period was from March 2020 to December 2021 – early strains, the 2nd period was the appearance of the Omicron strain. In the analysed group, there were 214 (79 %) people who had early strains of Covid-19 and 57 (21 %) of Omicron. A comparative assessment of the presence of PCS and its characteristics was carried out 3, 6, 9, 12 months after Covid-19.Results. Among patients who underwent NCI caused by early strains, CT-verified lung damage was recorded more often, which determined a higher frequency of hospitalizations. At the same time, the onset of Covid-19 presented with such symptoms as general weakness, lack of taste and smell; patients oftener bothered by periodic sensations of heat, increased body temperature, and shortness of breath. In the group of patients with NCI caused by the Omicron strain, comorbid pathology was determined oftener. PCS in groups of patients with NCI caused by early strains and the Omicron strain occurred with a frequency of 50.8% and 33.3%, respectively. In both groups, musculoskeletal manifestations remained the most common, with depression being commoner in the NCI group caused by early strains. The frequency of complaints characteristic of PCS remained at a high level for 6 months, a downward trend was noted by the 9th month after Covid-19. An increase in RD activity was found 3 months after the NCI in both groups.Conclusions. In NCI caused by early strains, a moderate and severe course of the disease, as well as the development of PCD within 12 months, was more common. PCS symptoms were most severe between 3 and 6 months and decreased by the 9th month of follow-up. RD activity increased and oftener observed 3 months after Covid-19, regardless of the transferred strain, with a tendency to decrease activity 9 months after the NCI.