Investigating clinical and laboratory findings and mortality rates among vaccinated and unvaccinated COVID-19 inpatients

Abstract

Aim: COVID-19 is an important public health problem in world and Turkey. The present study aimed to compare the clinical and laboratory findings and mortality rates among vaccinated and unvaccinated COVID-19 inpatients.Material and Method: We included patients receiving inpatient treatment in COVID-19 wards of our hospital between April 25 and October 22, 2021. The patients were divided into two groups: those with and without the COVID-19 vaccine. We extracted patient information from anamnesis files and the hospital information system. Then, we recorded the patients’ epidemiological and laboratory findings and vaccination status. Patients with at least two doses of the COVID-19 vaccine were considered “vaccinated.” We performed Fisher’s exact test and Chi-square test to analyze the data. All statistical analyses were performed in SPSS, and a p-value <0.05 was accepted as statistically significant.Results: The study included 63 vaccinated and 83 unvaccinated patients. With a mean age of 71.4±12.3 years, thirty (47.6%) of the vaccinated patients were females, and 33 (52.3%) were males. Of the unvaccinated ones, 40 (48.1%) were females, while 43 (51.8%) were males (mean age=52.2±14.4 years). The mean age was significantly higher in the vaccinated group than in the unvaccinated group (p<0.01). While 82.5% of the vaccinated patients received two doses, 17.5% received three doses of the COVID vaccine. Besides, 95.3% of the patients received their first dose of inactivated vaccine (Sinovac, China) and 4.7% of an mRNA vaccine (BioNTech, Germany). We found that comorbidities were significantly more prevalent in the vaccinated group than in the unvaccinated group (44 (69.8%) vaccinated and 34 (40.9%) unvaccinated patients had a comorbid disease, p<0.01). Among the accompanying diseases, hypertension was significantly more prevalent in the vaccinated group than in the unvaccinated group (p<0.01). Considering their laboratory findings, the vaccinated patients had significantly higher leukocyte, troponin, and ferritin values than the unvaccinated patients (p=0.008). Consequently, five (57.9) of the vaccinated patients and 4 (4.8%) of the unvaccinated patients died (p=0.05). Conclusion: Similar mortality rates between our vaccinated and unvaccinated patients may be attributed to the fact that the vaccinated group was relatively older, had more comorbid diseases, and received their second dose after an average of 100.6 days following their first dose of inactivated vaccine. In conclusion, further clinical research involving more cases that received different COVID-19 vaccines is needed to uncover the factors affecting mortality and morbidity among vaccinated patients.