The Long-Term Effects of COVID-19 on Pulmonary Function

Authors

• Emily Russell, Texas State UniversityFollow
• Chris Russian, Texas State UniversityFollow
• Kevin Collins, Texas State UniversityFollow

Abstract

Background: The COVID-19 pandemic has resulted in millions of hospitalizations and significant long-term health consequences. While acute COVID-19 symptoms are well-documented, the long-term pulmonary effects remain incompletely understood, particularly in patients with mild or asymptomatic infections. This review examines the long-term effects of COVID-19 on pulmonary function, including spirometry, lung volumes, diffusion capacity, and related outcomes such as exercise capacity and quality of life. Methods: A comprehensive literature search was conducted using CINAHL Ultimate, Google Scholar, and PubMed databases, yielding 10 articles for review (6 cohort studies, 3 review articles, and 1 systematic review and meta-analysis). Studies were assessed for quality using National Heart, Lung and Blood Institute Quality Assessment tools. Results: The most common pulmonary function impairment observed post-COVID-19 was reduced diffusion capacity (DLCO), occurring across all infection severity levels. Restrictive lung patterns were frequently observed in early recovery but showed improvement by 6-12 months post-infection. However, a subset of patients demonstrated persistent impairments beyond one year. Common patient-reported symptoms included fatigue (35-76%), dyspnea on exertion (35-65%), and cough (18-24%) at follow-up assessments. Mental health concerns, including anxiety and depression, were reported in 23-26% of patients. Notably, even patients with mild or asymptomatic infections demonstrated measurable functional impairments. Conclusions: COVID-19 causes multifaceted long-term effects on pulmonary function, physical capacity, and mental health. Comprehensive follow-up protocols including pulmonary function testing, muscle strength assessment, mental health screening, and pulmonary rehabilitation are warranted for all severity levels. Further research is needed to clarify pathophysiological mechanisms, optimize rehabilitation strategies, and evaluate the role of telemedicine in post-COVID care.

Author Bio(s)

Emily Russell, MSRC, RRT, RPFT, AE-C, is the Director of Clinical Education at Calhoun Community College. She is a licensed respiratory therapist in Alabama and holds advanced credentials in respiratory therapy, pulmonary function testing, and asthma education. Emily was an MSRC student at Texas State University during the preparation of this review paper.

Chris Russian, PhD, RRT, RRT-NPS, RPSGT, is the Interim Chair for the Department of Respiratory Care at Texas State University and the Program Coordinator for the Master of Science in Respiratory Care program. He is a licensed respiratory care practitioner in Texas.

Kevin Collins, PhD, RRT, RPFT, AE-C, is an Associate Professor in the Department of Respiratory Care at Texas State University. He is Director of the NIOSH Program and holds specialty credentials in pulmonary function testing and asthma education. He is a licensed respiratory care practitioner in Texas.

Recommended Citation

Russell E, Russian C, Collins K. The Long-Term Effects of COVID-19 on Pulmonary Function. The Internet Journal of Allied Health Sciences and Practice. 2026 Sep 01;24(3), Article 21.