ABSTRACT
Introduction: Italy was one of the first countries to be affected because of a severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) due to COVID-19 infection. However, the cases spread has not been consistent, featuring different tendencies over the months: in some periods cases escalated speedily and in others their expansion was indeed under restraint. Materials and methods: Based on Kaplan-Meier survival curves, the descriptive study includes the COVID-19 hospitalization in the Bolzano Province from February 2020 to March 2022 to analyze the frequency of such hospitalizations and the association between risk factors as age, sex, pandemic's wave, and the 30-day in-hospital mortality. Results: According to the results, starting from the first hospitalization, the 91.6% of in-hospital deaths occurred within 30 days, with an estimated 30-day's survival probability of 0.675 (95% CI: 0.649-0.699) for patients over 85 years of age;the estimate for male patients is 0.833 (95% CI: 0.820-0.846) and that for patients admitted during the initial wave is to 0.784 (95% CI: 0.751-0.813). Discussion and conclusions: The results of the study are in line with other studies in the literature at national and international level supporting the hypothesis that the rising age, the male sex and the first wave have played an important role in the COVID-19 mortality rate.