CLINICAL, RADIOLOGICAL AND FUNCTIONAL PULMONARY SEQUELAE IN RECOVERED COVID-19 PATIENTS: AN 18-MONTH DESCRIPTIVE FOLLOW-UP STUDY
Main Article Content
Keywords
COVID-19, pulmonary sequelae, DLCO, HRCT chest, long COVID, pulmonary fibrosis
Abstract
Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is primarily a respiratory illness but is increasingly recognized to result in persistent post-recovery sequelae, particularly involving the lungs. Survivors of moderate and severe COVID-19 frequently report prolonged dyspnoea, reduced exercise tolerance, and radiological abnormalities suggestive of residual interstitial lung disease.
Objectives: To assess clinical, radiological, and functional pulmonary sequelae in discharged COVID-19 patients and to evaluate factors influencing the severity and persistence of these abnormalities.
Methods: This descriptive observational study was conducted over 18 months at a tertiary respiratory care centre in Western Maharashtra. Fifty-seven adult patients previously hospitalized with moderate or severe COVID-19 pneumonia and hypoxaemia (SpO₂ <94%) were followed at 12, 24, and 48 weeks post-discharge. Clinical evaluation, 6-minute walk test (6MWT), pulmonary function tests (spirometry, lung volumes, DLCO), inflammatory markers, chest radiography, and HRCT chest were performed as per protocol.
Results: The mean age was 53.5 years; 70.1% were males. At 12 weeks, 95% of patients reported exertional dyspnoea, 79% fatigue, and 72% anxiety. Significant improvement was observed by 48 weeks, though 40% continued to report dyspnoea. At 12 weeks, 57.9% demonstrated desaturation on 6MWT, which reduced to 12.3% at 48 weeks. DLCO impairment was present in 80% at 12 weeks and persisted in 26% at 48 weeks. HRCT chest revealed residual reticulations in 26.3% patients at 48 weeks, suggesting post-COVID fibrotic changes.
Conclusion: Persistent pulmonary sequelae following moderate to severe COVID-19 are common and may persist up to one year post-recovery. Severity of acute illness, age, smoking history, and elevated inflammatory markers were associated with delayed recovery. Structured long-term respiratory follow-up is essential for early identification and management of post-COVID lung disease.
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Dr. Veena. H.N
Assistant professor1, Department of Respiratory Medicine, KMC&RI, Hubli, India.
Dr. H N Madhusudana
Professor2, Department of Anaesthesia, Classified Specialist, No 6 Air Force Hospital
Coimbatore, India.
Dr. Sudipta Adhikari
Assistant professor3, Department of Anaesthesia, Command Hospital Airforce Bengaluru, India.
Dr. Nikhil Kumar
Assistant Professor4*, Department of Anaesthesia, Command Hospital Airforce Bengaluru, India.
