Impact of Cardiorespiratory Fitness on COVID-19-Related Outcomes: The Exercise Testing and Health Outcomes Study (ETHOS).

Objective: To assess the association between cardiorespiratory fitness (CRF) and COVID-19-related health outcomes including mortality, hospitalization, and mechanical ventilation.

Patients And Methods: In a retrospective analysis of 750,302 patients included in the Exercise Testing and Health Outcomes Study, we identified 23,140 who had a positive result on COVID-19 testing between March 2020 and September 2021 and underwent a maximal exercise test in the Veterans Affairs Health Care System between October 1, 1999 to September 3, 2020. The association between CRF and risk for severe COVID-19 outcomes, including mortality, hospitalization due to COVID-19, and need for intubation was assessed after adjustment for 15 covariates.