Despite many short-term studies, the data on the long-term effects of the new coronavirus infection (COVID-19) is still scarce. Long-term respiratory symptoms and radiological and functional changes in COVID-19 survivors warrant the need for longitudinal studies to understand the process and timing of recovery better.
OBJECTIVE
To study clinical and functional changes of the body one year after the acute phase of COVID-19 in patients with severe and extremely severe disease associated with lung damage, with an assessment of functional and radiological abnormalities of the respiratory system, as well as parameters of physical endurance and quality of life.
MATERIALS AND METHODS
The study included 65 patients who were examined at 3, 6, and 12 months after the acute phase of COVID-19 with severe and extremely severe lung damage. Patients underwent multislice computed tomography (MSCT) of the lungs, a comprehensive study of respiratory function (spirography, body plethysmography, and diffusion test), a 6-minute step test with a quantitative assessment of dyspnea both during exercise and in everyday life; quality of life was assessed using the EuroQol EQ-5D-5L questionnaire.
RESULTS
MSCT showed a gradual regression of abnormalities; however, radiological changes of varying severity persisted after 12 months in 63% of patients. After a year of observation, the most significant radiological abnormalities were «frosted glass» and reticular changes. After 12 months, restrictive disorders persisted in 20% of patients, and the diffusion capacity of the lungs was reduced in 51% of patients. After 3 months, a significant proportion of patients (94%) experienced physical restrictions and anxiety-depressive disorders (68%), significantly reducing their quality of life. After 12 months, a mild restriction of physical activity persisted in 46% of patients, and the rate of anxiety-depressive disorders decreased by more than twice (29%).
CONCLUSION
Survivors of severe COVID-19 have persistent impairment of the diffusion capacity of the lungs and radiological changes throughout the year after COVID-19. Over time, the physical and psychological status recovered; however, after 12 months, half of the patients had a mild restriction of physical activity and difficulty in daily activities, and 1/3 of the patients still experienced moderate anxiety and depression.
