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.

Keywords

• COVID-19
• vaccine
• mortality
• morbidity

References

1. WHO Coronavirus (COVID-19) Dashboard. Available online: https://covid19.who.int/ 2022
2. Guan WJ, Liang WH, Zhao Y, et al. Comorbidity and its impact on 1590 patients with COVID-19 in China: a nation wide analysis. Eur Respir J 2020; 55: 2000547.
3. Ersan G, Rollas K, Atalay S, et al. [Analysis of 65 years old and over patients with full dose vaccination by inactive vaccine and without vaccination admitted to hospital with SARS-Cov-2 PCR positivity]. Klimik Derg 2022; 35: 64-7.
4. Chen Y, Klein SL, Garibaldi BT, et al. Aging in COVID-19: Vulnerability, immunity and intervention. Ageing Res Rev 2021; 65: 101205.
5. Tregoning JS, Flight KE, Higham SL, Wang Z, and Pierce BF. Progress of the COVID-19 vaccine effort: viruses, vaccines and variants versus efficacy, effectiveness and escape. Nat Rev Immunol 2021; 21: 626-36.
6. Gavriatopoulou M, Stathopoulos IN, Korompoki E, et al. Emerging treatment strategies for COVID-19 infection. Clin Exp Med 2021; 21: 167-79.
7. Wang Q, Yang L, Jin H, Lin L.Vaccination against COVID-19: A systematic review and meta-analysis of acceptability and its predictors. Prev Med 2021; 150: 106694.
8. Johnson AG, Amin AB, Ali AR, et al. COVID-19 ıncidence and death rates among unvaccinated and fully vaccinated adults with and without booster doses during periods of delta and omicron variant emergence—25 U.S. Jurisdictions, April 4–December 25, 2021. MMWR Morb Mortal WklyRep 2022; 71: 132-8.

9. Xu S, Huang R, Sy LS, et al. COVID-19 Vaccination and Non-COVID-19 Mortality Risk - Seven Integrated Health Care Organizations, United States, December 14, 2020-July 31, 2021. MMWR Morb Mortal Wkly Rep 2021; 70: 1520-4.
10. Bernal JL, Andrews N, Gower C, et al. Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on COVID-19 related symptoms, hospital admissions, and mortality in older adults in England: test negative case-control study. BMJ 2021; 373: n1088.
11. Haas EJ, Angulo F, McLaughlin JM, et al. Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalisations, and deaths following a nationwide vaccination campaign in Israel: an observational study using national surveillance data. Lancet 2021; 397: 1819-29.
12. Tenforde MW, Self WH, Adams K, et al. Association between mRNA vaccination and COVID-19 hospitalization and disease severity. JAMA 2021; 326: 2043-54.
13. Onder G, Rezza G, Brusaferro S. Case-fatality rate and characteristics of patients dying in relation to COVID-19 in Italy. JAMA 2020; 323: 1775-6.
14. Wu Z, Mc Googan JM. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: Summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention. JAMA 2020; 323: 1239-4.
15. Wu C, Chen X, Cai Y, et al. Risk factors associated with acute respiratory distress syndrome and death in patients with coronavirus disease 2019 pneumonia in Wuhan, China. JAMA Intern Med 2020; 180: 934-43.
16. Garibaldi BT, Fiksel J, Muschelli J, et al. Patient trajectories among persons hospitalized for COVID-19: a cohort study. Ann Intern Med 2021; 174: 33-41.
17. Durusu-Tanriover M, Doğanay HL, Akova M, et al. Efficacy and safety of an inactivated whole-virion SARS-CoV-2 vaccine (CoronaVac): interim results of a double-blind, randomised, placebo-controlled, phase 3 trial in Turkey. Lancet 2021; 398: 213-22.
18. Mok CKP, Cohen CA, Cheng SMS, et al. Comparison of the immunogenicity of BNT162b2 and CoronaVac COVID-19 vaccines in Hong Kong. Respirology 2021; 7: 301-10.
19. Dagan N, Barda N, Kepten E, et al. BNT162b2 mRNA COVID-19 vaccine in a nationwide mass vaccination setting. N Engl J Med 2021; 384: 1412-23.
20. Bernal JL, Andrews N, Gower C, et al. Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on COVID-19 related symptoms, hospital admissions, andmortality in older adults in England: test negative case-control study. BMJ 2021; 373: n1088.
21. Mhawish H, Mady A, Alaklobi F, et al. Comparison of severity of immunized versus non-immunized COVID-19 patients admitted to ICU: A prospective observational study. Ann Med Surg (London) 2021; 71: 102951.
22. Olson SM, Newhams MM, Halasa NB, et al. Effectiveness of BNT162b2 vaccine against critical COVID-19 in adolescents. N Engl J Med 2022; 386: 713-23.
23. Muthukrishnan J , Vardhan V , Mangalesh S, et al. Vaccination status and COVID-19 related mortality: A hospital based cross sectional study. Med J Armed Forces India 2021; 77: 278–82.