Internações por covid-19 no estado do Maranhão: análise da gravidade, situação vacinal e fatores associados ao óbito

Abstract

Studies identifying the characteristics of hospitalizations and deaths from COVID-19 compared to vaccination status are scarce, especially in the state of Maranhão. The objective of this study is to analyze the severity of hospitalizations and factors associated with in-hospital death from COVID-19 in the years 2021 and 2022 in the state of Maranhão. This is a retrospective cohort study, based on secondary data and covering the state in the years 2021 and 2022. Extreme Gradient Boosting (XGBoost) machine learning algorithm was used for data analysis, and the SHapley Additive exPlanations (SHAP) metric was used to assess the relevance of each predictor variable. The TRIPOD protocol was also used to standardize the development of learning algorithms. For the purpose of classifying vaccination status, individuals who received the complete basic schedule (two doses of the Coronavac, Pfizer, or AstraZeneca vaccines) or a single dose (Janssen vaccine), with an interval of 14 days after completing the schedule, were considered vaccinated. For classification of the severity of the hospitalization outcome, death, non-severe discharge (when ventilatory support and/or intensive care unit (ICU) admission were not required), and severe discharge (when ventilatory support and/or ICU admission were required) were considered. Regarding hospitalizations, in the year 2021, 13,257 individuals were hospitalized with COVID-19, of which 6,425 (48.46%) were discharged after non-severe hospitalization, 1,573 (11.87%) were discharged after severe hospitalization, and 5,259 (39.67%) died. In all three outcomes of hospitalization evolution (non-severe discharge, severe discharge, and death), the number of unvaccinated individuals is much higher when compared to vaccinated individuals, being respectively 5,836, 1,398, and 4,704. Regarding factors associated with death from COVID-19 following the onset of vaccination, the study identified that in the years 2021 and 2022, Maranhão recorded 14,323 hospitalizations for COVID-19, with 90.97% occurring only in 2021. The majority of hospitalized individuals were aged 60 to 69 years (19.47%), male (57.15%), and self-declared brown race/color (77.02%). The main variables related to death were: ICU admission, followed by advanced age, location of hospitalization in the interior of the state, vaccination status, use of ventilatory support, and male sex. Our results reinforce the important role of vaccination in reducing the severity of hospitalizations for COVID-19. With the immunization of the state's population, few individuals who were hospitalized and vaccinated progressed to severe discharge and death. Additionally, our results can be used as evidence and support for decision-making regarding the provision of health services and prognosis of COVID-19 patients requiring intensive care,

contributing to the improvement of clinical management and ultimately informing decision- making regarding other potential health crises in the country.