Exercise intolerance in post-coronavirus disease 2019 survivors after hospitalisation

• Published in: ERJ open research Vol. 9; no. 3; p. 538
• Main Authors: Lafetá, Mariana L, Souza, Vitor C, Menezes, Thaís C F, Verrastro, Carlos G Y, Mancuso, Frederico J, Albuquerque, André Luis P, Tanni, Suzana E, Izbicki, Meyer, Carlstron, Júlio P, Nery, Luiz Eduardo, Oliveira, Rudolf K F, Sperandio, Priscila A, Ferreira, Eloara V M
• Format: Journal Article
• Language: English
• Published: England European Respiratory Society 01-05-2023
• Subjects: Original s
• ISSN: 2312-0541; 2312-0541
• DOI: 10.1183/23120541.00538-2022

Post-coronavirus disease 2019 (COVID-19) survivors frequently have dyspnoea that can lead to exercise intolerance and lower quality of life. Despite recent advances, the pathophysiological mechanisms of exercise intolerance in the post-COVID-19 patients remain incompletely characterised. The objectives of the present study were to clarify the mechanisms of exercise intolerance in post-COVID-19 survivors after hospitalisation.
This prospective study evaluated consecutive patients previously hospitalised due to moderate-to-severe/critical COVID-19. Within mean±sd 90±10 days of onset of acute COVID-19 symptoms, patients underwent a comprehensive cardiopulmonary assessment, including cardiopulmonary exercise testing with earlobe arterialised capillary blood gas analysis.
87 patients were evaluated; mean±sd peak oxygen consumption was 19.5±5.0 mL·kg
·min
, and the tertiles were ≤17.0, 17.1-22.2 and ≥22.3 mL·kg
·min
. Hospitalisation severity was similar among the three groups; however, at the follow-up visit, patients with peak oxygen consumption ≤17.0 mL·kg
·min
reported a greater sensation of dyspnoea, along with indices of impaired pulmonary function, and abnormal ventilatory, gas-exchange and metabolic responses during exercise compared to patients with peak oxygen consumption >17 mL·kg
·min
. By multivariate logistic regression analysis (receiver operating characteristic curve analysis) adjusted for age, sex and prior pulmonary embolism, a peak dead space fraction of tidal volume ≥29 and a resting forced vital capacity ≤80% predicted were independent predictors of reduced peak oxygen consumption.
Exercise intolerance in the post-COVID-19 survivors was related to a high dead space fraction of tidal volume at peak exercise and a decreased resting forced vital capacity, suggesting that both pulmonary microcirculation injury and ventilatory impairment could influence aerobic capacity in this patient population.