Severity does not impact on exercise capacity in COVID-19 survivors

Area of Science:

• Pulmonology
• Cardiology
• Exercise Physiology

Background:

• Limited data exists on how acute illness severity impacts long-term exercise capacity and ventilatory efficiency in COVID-19 survivors.
• Cardiopulmonary exercise testing (CPET) is crucial for evaluating these functional outcomes.

Purpose of the Study:

• To assess the influence of acute COVID-19 severity on exercise capacity, pulmonary function, and chest imaging in survivors.
• To analyze post-COVID-19 functional recovery based on initial disease classification (mild-to-moderate, severe, critical).

Main Methods:

• A post-hoc analysis of a prospective cohort study involving 75 COVID-19 survivors.
• Patients were categorized by acute illness severity: mild-to-moderate (18), severe (18), and critical (39).
• Evaluated outcomes included cardiopulmonary exercise test (CPET) parameters, pulmonary function tests (PFTs), and chest CT scans at a mean follow-up of 97 days.

Main Results:

• Pulmonary function tests and CT findings showed similar residual involvement across all severity groups.
• Exercise capacity, measured by peak oxygen consumption, was comparable among groups (mean % predicted: 83-84%).
• Ventilatory efficiency, assessed by the ventilation-to-carbon dioxide output slope, was preserved and similar across groups (mean: 27.1-29.8).

Conclusions:

• Acute COVID-19 severity does not significantly impact exercise capacity or ventilatory efficiency in survivors at approximately three months post-discharge.
• COVID-19 survivors exhibit a ventilatory response within normal limits, irrespective of initial disease severity.
• These findings suggest a generally good functional recovery concerning exercise physiology, independent of initial illness severity.