Long COVID and Post-exertional Pulmonary Diffusion

Completed

• Conditions: Alveolar Lung Disease; Exercise Intolerance; Long COVID; Breathlessness; Pulmonary Gas Exchange
• Interventions: Diagnostic Test: Lung volumes, spirometry and standard single-breath DLCO were measured at rest while combined DLNO and DLCO were measured at rest and post-exercise

• Registration Number: NCT05430503
• Lead Sponsor: IRCCS Azienda Ospedaliera Universitaria San Martino - IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy

Brief Summary

Aim of investigators was to study whether abnormalities of lung diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) in long COVID may have a clinical impact in relation to exercise intolerance.

Detailed Description

Prolonged recovery from acute coronavirus disease 2019 (long COVID) is characterized in about 30% of subjects from breathlessness and fatigue also during daily activities often associated to decreased lung diffusing capacity for carbon monoxide (DLCO) at rest. Aim of investigators was to study whether abnormalities of lung diffusing capacity for nitric oxide (DLNO) and DLCO in long COVID may have a clinical impact in relation to exercise intolerance. Combined DLNO and DLCO were simultaneously measured at rest and immediately after a short bout of treadmill walking in 32 dyspneic subjects ≥3 months after the COVID-19 acute phase. A group of healthy subjects served as a control group.

Study Timeline

• Study Start: 2022-05-24
• Status Verified: 2022-06
• Primary Completion: 2022-06-15
• Study Completion: 2022-06-15
• Study First Submitted: 2022-06-19
• Study First Submitted QC: 2022-06-23
• Last Update Submitted: 2022-06-23
• Study First Posted: 2022-06-24
• Last Update Posted: 2022-06-24

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 32

Inclusion Criteria

• History of dyspnea, fatigue, and exercise intolerance persisting or occurring at least 3 months after the COVID-19 acute phase and lasting ≥2 months.

Exclusion Criteria

• History of diseases potentially causing dyspnea or affecting pulmonary gas transport, i.e., bronchial asthma, lung bullous disease, chronic obstructive pulmonary disease, pulmonary interstitial fibrosis or vasculitis, hematological diseases, systemic collagen diseases, congestive heart failure, liver or renal diseases, and morbid obesity.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Healthy controls	Lung volumes, spirometry and standard single-breath DLCO were measured at rest while combined DLNO and DLCO were measured at rest and post-exercise	Anthropometrically-matched healthy subjects, without history of COVID-19 and vaccinated against SARS-CoV-2 infection.
Long COVID	Lung volumes, spirometry and standard single-breath DLCO were measured at rest while combined DLNO and DLCO were measured at rest and post-exercise	Caucasian subjects with a history of SARS CoV-2 infection confirmed by nasopharyngeal swab with real-time polymerase-chain reaction were included in the study. They were referred to investigators' pulmonary function laboratory after being tested negative for SARS-CoV-2, because of dyspnea, fatigue, and exercise intolerance persisting or occurring at least 3 months after the COVID-19 acute phase and lasting ≥2 months.

Primary Outcome Measures

Name	Time	Method
Combined DLNO and DLCO changes after mild exercise	through study completion, an average of 6 months	pulmonary gas exchange abnormalities in dyspneic long COVID subjects

Trial Locations

Locations (1)

Ospedale Policlinico San Martino IRCCS - S.S. Fisiopatologia Respiratoria; 🇮🇹 Genoa, Italy