Mortality due to respiratory infections: an alert study before COVID-19 pandemic.

Objective: Respiratory tract infections remain a common problem in clinical practice with high morbidity and mortality worldwide. In Portugal, pneumonia was the third leading death cause in 2018. Due to COVID-19 pandemic, there is a growing concern about the burden of respiratory diseases and preventable risk factors. The present study started before the pandemic and its aim was to determine the occurrence of pneumonia/bronchopneumonia in a postmortem series and to characterize its circumstantial context. Methods: A retrospective anatomopathological study was performed on cases with acute pneumonia/bronchopneumonia at the Medicolegal Portuguese Institute (2011-2017). Results: In an autopsy series of 737 patients, 521 were male and 675 presented comorbidities. The mean age was 63.87 ± 19.8 years. The most common acquisition site was community (65.1%), as natural death (65.5%). Concerning the manner of death, most cases (48.0%) were sudden deaths, followed by accidents (29.2%). A statistically significant association was observed between the medicolegal etiology and the place of infection acquisition, with higher prevalence of natural obitus (91.0%) in community-acquired pneumonia/bronchopneumonia versus higher prevalence of violent obitus in hospital-acquired pneumonia/bronchopneumonia (82.1%) (p < 0.001). Conclusions: Forensic anatomopathological postmortem data may contribute to better understand community and hospital pulmonary infections.