DOES COVID 19 VACCINATION PREVENT LIVER INJURY? – A LONGITUDINAL COMPARISON BETWEEN COVID 19 VACCINATED PATIENTS AND COVID 19 UNVACCINATED PATIENTS

ABSTRACT

Background: The 2019 novel coronavirus (COVID-19) has been associated with elevated liver enzymes, which has seen to be associated with a higher mortality rate in COVID-19 infected patients. With a global vaccination rate under 50%, as of November 2021, we will continue to see patients admitted for COVID-19 infection. We have done this study to further evaluate the relationship between development of transaminitis and its relation to vaccination status and to see if vaccination prevented liver injury in COVID-19 patients. Methods: A retrospective study was performed between October 2019 and October 2021 on patients infected with COVID-19. A total of three hundred and fifty patient charts were included in the study. Patient data regarding age, sex, comorbidities, vaccination status, vaccine manufacturer, mortality, and length of stay data were reviewed. Patients were then divided into two groups (Vaccinated vs Unvaccinated ), data was then matched for their age, sex, and comorbidities using propensity score matching. Results: Each group had thirty-nine patients after propensity score matching. The average age in both groups was 58.4±13.3. Twenty-one females were in a non-vaccinated group and twenty females in the vaccinated group. The average number of days to infection from the last COVID-19 vaccine was 132±57. The vaccinated group showed a significant reduction in the incidence of liver injury with respect to AST (42±13 vs. 93.3±35, P< 0.02, 95% CI), ALT (50±10 vs. 97.4±45.5 P<0.04), and ALP 65±15.2 vs. 93±35.6 P<0.01) compared to unvaccinated patients. The vaccinated patient group showed a reduced length of stay compared to the unvaccinated group ( 10.6 ± 4.8 vs. 18.1 ± 8.1, P<0.05). The vaccinated patient group showed a decrease in mortality as compared to the unvaccinated group (17 vs. 8, P<0.05). Conclusion: After a thorough review of COVID infected patients, liver enzyme abnormalities were evaluated in vaccinated and unvaccinated patients. ALT, AST, and ALP in vaccinated patients were found to be significantly lower in as compared to unvaccinated patients. Hospital length of stay and mortality rate were both found to be lower in vaccinated patients compared to unvaccinated patients. Recent vaccination status leading to decreased infection severity may relate to the lack of significant and dramatic increase in liver enzyme levels and may present as confounding factors. Major limitation in the study was the small sample size and future studies with a larger sample size can deliver a better perspective.