Impact of the COVID-19 pandemic in mortality due to respiratory diseases: A comparative analysis of 2021 and 2020 vs 2019 in Spain

Introduction: We previously reported an increase in respiratory mortality in 2020 in Spain after COVID-19. It is unclear if this rise is sustained in the longer-term. We aimed to determine whether respiratory mortality in 2021 in Spain returned to pre-pandemic levels. Material and Methods: In an observational, large study using official INE data, we explored deaths due to respiratory diseases, that is, all causes of death by the standard WHO list of diseases of the respiratory system plus COVID-19, tuberculosis and lung cancer. Using the latest available official data of Spain, we analysed changes in the mortality pattern in Spain from January 2019 to December 2021. We endorsed STROBE guidance for observational research. Results: There were 98,714 deaths due to respiratory diseases in 2021 in Spain, corresponding to 21.9% of all deaths, becoming second in the ranking of causes of death. Respiratory diseases mortality in Spain has not returned to pre-pandemic levels in 2021, still with an increase of 30.3% (95% C.I. 30.2-30.4) compared to rates in 2019. All respiratory-specific causes of death decreased in 2021, except for lung cancer, that increased in women and decreased in men compared to 2019 (both p <0.05). In a multivariate analysis some established risk factors for respiratory diseases mortality were confirmed, such as male gender and older age; further, an association with reduced mortality in rural Spain was observed, still with a large geographical variability. Conclusions: The COVID-19 pandemic has had a lasting impact on deaths due to respiratory diseases and certain specific causes of death in 2021, and it has disproportionately affected certain regions.