Risk factors and the impact of vaccination on mortality in COVID-19 patients

Abstract

INTRODUCTION:The novel coronavirus disease (COVID-19) pandemic has had a profound global impact economically, socially, and in many other areas. As vaccines are developed and introduced, their effect on the disease on both, the global and individual scale is a subject of intense curiosity. This study aimed to evaluate the relationship between risk factors for hospitalization, disease severity, and vaccination status in COVID-19 inpatients in a pandemic hospital. METHODOLOGY: Patients hospitalized for COVID-19 between June and September 2021 were retrospectively analyzed in three groups: unvaccinated, incompletely vaccinated, and fully vaccinated. Disease severity was classifi ed as moderate, severe, or critical according to World Health Organization criteria, and mortality risk factors and the prognostic effect of vaccination were analyzed. RESULTS: The study included 486 patients, 228 women (46.9 %) and 258 men (53.1 %), with a mean age of 55.4 ± 16.5 years. Of these, 264 patients (54.3 %) were unvaccinated, 147 (30.2 %) were incompletely vaccinated, and 75 (15.4 %) were fully vaccinated. Older age, higher Charlson Comorbidity Index, greater disease severity, and being unvaccinated or incompletely vaccinated were associated with higher mortality. CONCLUSIONS: The results of our study indicate that age, disease severity, comorbidities, and vaccination status were factors affecting COVID-19 mortality. Our fi ndings support that full vaccination reduces COVID-19 -related mortality rates, disease severity, and length of hospital stay. However, large-scale studies with larger patient populations are needed (Tab. 2, Ref. 22).

Evaluation of clinical outcomes of vaccinated and unvaccinated patients with hospitalization for COVID-19

“…Moreover, while age, CCI, and vaccination status were the independent factors associated with mortality in general cohort, CCI was the only independent factor in vaccinated patients. Similarly, in the study of Sezen et al, mortality was found to be significantly higher in patients with CCI ≥1 [15].…”

“…However, studies comparing the mortality rates of vaccinated and unvaccinated patients, which take into account the demographic and clinical characteristics of patients in the delta variant dominant period, are limited. In the study of Sezen et al, mortality rates were higher in patients with advanced age, high CCI, and incomplete vaccination [15]. Alsaffar et al reported that vaccination significantly reduced the need for ICU admission (P 5 0.063, OR 5 0.476) and death (P 5 0.034, OR 5 0.378).…”

Comparison of Clinical Outcomes of Coronavac Vaccinated and Unvaccinated Older Adults With Hospitalized Covid-19

“…Many studies have revealed that COVID-19 patients with underlying diseases have increased risk of poor prognosis (15)(16)(17)(18). In the study of Yavuz et al, chronic pulmonary disease, malignancy, chronic kidney disease, and cardiovascular diseases were reported as independent risk factors for mortality (17).…”

International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC). A new collaborative global platform for global clinical trials targeting post-COVID19 patients.

“…hypertensive, immunosuppressed, and with chronic lung or heart diseases before COVID-19 are at greater risk of developing the severe condition and having a poor prognosis, requiring intensive care (8)(9)(10) .…”

“…Despite the rapid development, production of vaccines, and effective treatments, COVID-19 continues to generate serious and widespread repercussions for health (8,11,12) . In cases considered to be symptomatic, the manifestations usually appear on the fifth day of infection, with a higher rate of hospitalization on the seventh day and worsening of the infection, evolving to ARDS on the eighth day (13) .…”