Two-year diffusion capacity trajectory in COVID-19 pneumonia survivors

Area of Science:

• Pulmonology
• Infectious Diseases
• Respiratory Medicine

Background:

• Reduced diffusion capacity (DLCO) is a known post-COVID-19 pneumonia complication.
• Long-term respiratory sequelae require further investigation in COVID-19 survivors.

Purpose of the Study:

• To assess the restoration of DLCO over 24 months in COVID-19 pneumonia survivors.
• To compare DLCO recovery across different COVID-19 severity groups (moderate, severe, critical).

Main Methods:

• Longitudinal study of 317 COVID-19 pneumonia survivors.
• Categorization into moderate, severe, and critical disease based on clinical parameters.
• DLCO measurements at 3, 6, and 24 months post-discharge for patients with initial DLCO < 80%.

Main Results:

• DLCO impairment was more severe in critical cases at 3 months.
• All subgroups showed similar improvement trajectories, with no significant differences in recovery over time.
• At 24 months, 65% of patients still had DLCO < 80%, and 40% had DLCO < 70%.

Conclusions:

• COVID-19 survivors show DLCO improvement over 24 months, irrespective of initial disease severity.
• A majority of patients with initial DLCO impairment do not achieve normal DLCO levels by 24 months.
• Persistent DLCO reduction highlights the need for ongoing respiratory monitoring and rehabilitation in post-COVID-19 patients.