ABSTRACT
Whether vaccination confers a protective effect against progression after hospital admission for COVID-19 remains to be elucidated. Observational study including all the patients admitted to San Paolo Hospital in Milan for COVID-19 in 2021. Previous vaccination was categorized as: none, one dose, full vaccination (two or three doses >14 days before symptoms onset). Data were collected at hospital admission, including demographic and clinical variables, age-unadjusted Charlson Comorbidity index (CCI). The highest intensity of ventilation during hospitalization was registered. The endpoints were in-hospital death (primary) and mechanical ventilation/death (secondary). Survival analysis was conducted by means of Kaplan-Meier curves and Cox regression models. Effect measure modification by age was formally tested. We included 956 patients: 151 (16%) fully vaccinated (18 also third dose), 62 (7%) one dose vaccinated, 743 (78%) unvaccinated. People fully vaccinated were older and suffering from more comorbidities than unvaccinated. By 28 days, the risk of death was of 35.9% (95%CI: 30.1-41.7) in unvaccinated, 41.5% (24.5-58.5) in one dose and 28.4% (18.2-38.5) in fully vaccinated (p = 0.63). After controlling for age, ethnicity, CCI and month of admission, fully vaccinated participants showed a risk reduction of 50% for both in-hospital death, AHR 0.50 (95%CI: 0.30-0.84) and for mechanical ventilation or death, AHR 0.49 (95%CI: 0.35-0.69) compared to unvaccinated, regardless of age (interaction p > 0.56). Fully vaccinated individuals in whom vaccine failed to keep them out of hospital, appeared to be protected against critical disease or death when compared to non-vaccinated. These data support universal COVID-19 vaccination.
ABSTRACT
BACKGROUND: Mortality rate from COVID-19 in Italy is among the world's highest. We aimed to ascertain whether there was any reduction of in-hospital mortality in patients hospitalised for COVID-19 in the second-wave period (October 2020-January 2021) compared to the first one (February-May 2020); further, we verified whether there were clusters of hospitalised patients who particularly benefitted from reduced mortality rate. METHODS: Data collected related to in-patients' demographics, clinical, laboratory, therapies and outcome. Primary end-point was time to in-hospital death. Factors associated were evaluated by uni- and multivariable analyses. A flow diagram was created to determine the rate of in-hospital death according to individual and disease characteristics. RESULTS: A total of 1561 patients were included. The 14-day cumulative incidence of in-hospital death by competing risk regression was of 24.8% (95% CI: 21.3-28.5) and 15.9% (95% CI: 13.7-18.2) in the first and second wave. We observed that the highest relative reduction of death from first to second wave (more than 47%) occurred mainly in the clusters of patients younger than 70 years. CONCLUSIONS: Progress in care and supporting therapies did affect population over 70 years to a lesser extent. Preventive and vaccination campaigns should focus on individuals whose risk of death from COVID-19 remains high.
ABSTRACT
OBJECTIVE: We aimed to document data on the epidemiology and factors associated with clinical course leading to death of patients hospitalised with COVID-19. METHODS: Prospective observational cohort study on patients hospitalised with COVID-19 disease in February-24th/May-17th 2020 in Milan, Italy. Uni-multivariable Cox regression analyses were performed. Death's percentage by two-weeks' intervals according to age and disease severity was analysed. RESULTS: A total of 174/539 (32.3%) patients died in hospital over 8228 person-day follow-up; the 14-day Kaplan-Meier probability of death was 29.5% (95%CI: 25.5-34.0). Older age, burden of comorbidities, COVID-19 disease severity, inflammatory markers at admission were independent predictors of increased risk, while several drug-combinations were predictors of reduced risk of in-hospital death. The highest fatality rate, 36.5%, occurred during the 2nd-3rd week of March, when 55.4% of patients presented with severe disease, while a second peak, by the end of April, was related to the admission of older patients (55% ≥80 years) with less severe disease, 30% coming from long-term care facilities. CONCLUSIONS: The unusual fatality rate in our setting is likely to be related to age and the clinical conditions of our patients. These findings may be useful to better allocate resources of the national healthcare system, in case of re-intensification of COVID-19 epidemics.