Long Term Pulmonary Complications After COVID 19 A Study of Post Viral lung Fibrosis and Respiratory Dysfunction

Abstract

Background: Long-term pulmonary complications from COVID-19, including post-viral fibrosis and respiratory dysfunction, present significant public health challenges. Limited data exist on the prevalence and outcomes of these conditions. Objective: To investigate the prevalence, risk factors, and outcomes of post-viral pulmonary fibrosis and respiratory dysfunction in COVID-19 survivors using a multidisciplinary approach. Method: A multicenter, longitudinal cohort study was conducted at a tertiary-level hospital in Rajshahi, Bangladesh, between June 2022 and July 2024. A total of 104 patients were enrolled. Data collection included clinical assessments, high-resolution computed tomography (HRCT), pulmonary function tests (PFTs), and patient-reported outcome measures. Statistical analyses were performed to identify predictors and quantify outcomes. Results: Among the 104 patients, 62% exhibited HRCT abnormalities, including ground-glass opacities and reticulation. Persistent dyspnea was reported by 48% of patients, while 38% experienced reduced exercise tolerance. Pulmonary function tests showed a mean reduction in DLCO by 25%, and 42% of patients demonstrated restrictive ventilatory defects. Fibrotic changes persisted in 31% of cases at the 18-month follow-up. Advanced age (>60 years) and ICU admission were significant risk factors, with a relative risk of 3.2 (95% CI: 2.1–4.7). Patients requiring mechanical ventilation had a higher likelihood of developing fibrosis. Rehabilitation programs improved functional outcomes in 68% of participants, reducing dyspnea scores by 40% and improving exercise capacity by 25% on average. Conclusions: Post-viral fibrosis and respiratory dysfunction are prevalent among COVID-19 survivors, significantly impacting quality of life and healthcare utilization. Early identification and targeted interventions are essential to mitigating these complications and improving patient outcomes.