Profile of adult patients hospitalized with COVID-19 before and after introduction of SARS-CoV-2 vaccines

Background: During the COVID-19 pandemic, the early prioriti-zation of SARS-CoV-2 vaccines for older adults may have affected the characteristics of hospitalized COVID-19 patients over time. Aim: To compare the clinical characteristics and outcomes of adult patients admitted for COVID-19 before (PER1) and after (PER2) the initiation of mass vaccination for SARS-CoV-2. Methods: Data on age, gender, comorbidities, complications, and outcomes of adult patients hospitalized for COVID-19 in a private clinic of Santiago, Chile, were collected. Scores for COVID-19 severity and nutritional risk were calculated. Results: In PER2, patients were younger but had similar comorbidities, except for a higher prevalence of overweight and obesity compared to PER1. Unvaccinated COVID-19 patients in PER2 required more invasive ventilatory support (38.9% vs. 14.3%, p = 0.03) and had a higher severity score (six) than vaccinated patients (five, p = 0.048). The variables that best predicted mortality were age > 60 years (OR 28,995) and the presence of nutritional risk (OR 5,246). Discussion: Changes in the profile and outcomes of hospita-lized patients during the COVID-19 pandemic are associated with the prioritization of SARS-CoV-2 vaccines and their protective effect in and disease in older adults.