Effect of vaccination on the course of new coronavirus infection in patients over 50 years of age: a retrospective study

INTRODUCTION. The new coronavirus infection (NCI) COVID-19 has brought significant changes in the structure of morbidity and mortality of the whole mankind, especially it affected people of middle, old and elderly age, which is associated both with the peculiarities of age-related changes in the human body and onset of many comorbidities in patients of older age group. That is why timely vaccination and regular revaccination against NCI play a particularly important role in the course of the disease and prevention of complications in this category. Due to the inclusion of COVID-19 in the list of sea-sonal diseases, the abolition of mandatory revaccination against SARS-CoV-2 coronavirus is currently being discussed, but it should most likely remain mandatory for certain high-risk groups, including those over 50 years of age. In this study, we evaluated the impact of vaccination on the course of COVID-19 in patients exactly at this age, taking into account all the main indicators of the clinical course of the disease. Comparison of the results and determination of their statistical significance indicate that vaccination, indeed, reduces the risks of moderate and severe course, decreases the average duration of hospitalization and positively affects a number of indicators of the course of COVID-19 in people over 50 years of age.

OBJECTIVE. To evaluate the course of NСI in vaccinated and unvaccinated patients over 50 years of age.

MATERIALS AND METHODS. In the course of the study, a retrospective evaluation of the COVID-19 course in vaccinated and unvaccinated patients over 50 years of age was carried out. A homogeneous sample of 56 people (age median of both samples - 63 years, from 50 to 83 years) from the patients treated at the Clinic of Naval Therapy of the Kirov Military Medical Academy in the period from April 2020 to February 2021 was determined for the study. The total sample was divided into two subgroups: homogeneous according to the criterion of vaccine receipt. Thus, a group of vaccinated (group 1) of 27 people and unvaccinated (group 2) of 29 people was distinguished. The groups were compared according to the main significant indicators of the disease course, including period of hospitalization, main complaints, clinical and biochemical blood tests, results of instrumental investigations and treatment outcomes.

RESULTS. The data obtained in the course of the study indicate the ambiguity of the problem of the vaccination effect on the course of NCI in patients over 50 years of age, since at this age the disease inevitably enters the synergy with concomitant somatic pathology and general age-related changes. Despite this, statistically significant differences were found between the course of the disease in the studied groups, indicating a beneficial effect of vaccination on the rate of patients’ recovery from the infection and on its development in general.

CONCLUSION. Vaccination against NCI in people over 50 years of age facilitates recovery from the disease and reduces the risks of complications, making it essential for this age group. Making vaccination mandatory for people over 50 years of age will help reduce the burden on health care and the economic costs of medical support.

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