A prospective study of pulmonary outcomes and chest computed tomography in the first year after COVID-19.

COVID-19 primarily affects the respiratory system. We aimed to evaluate how pulmonary outcomes develop after COVID-19 by assessing participants from the first pandemic wave prospectively 3 and 12 months following hospital discharge. Pulmonary outcomes included self-reported dyspnoea assessed with the modified Medical Research Council dyspnoea scale, 6-min walk distance (6MWD), spirometry, diffusing capacity of the lung for carbon monoxide (D LCO), body plethysmography and chest computed tomography (CT). Chest CT was repeated at 12 months in participants with pathological findings at 3 months. The World Health Organization (WHO) ordinal scale for clinical improvement defined disease severity in the acute phase. Of 262 included COVID-19 patients, 245 (94%) and 222 (90%) participants attended the 3- and 12-month follow-up, respectively. Self-reported dyspnoea and 6MWD remained unchanged between the two time points, while D LCO and total lung capacity improved (0.28 mmol·min-1·kPa-1, 95% CI 0.12-0.44, and 0.13 L, 95% CI 0.02-0.24, respectively). The prevalence of fibrotic-like findings on chest CT at 3 and 12 months in those with follow-up chest CT was unaltered. Those with more severe disease had worse dyspnoea, D LCO and total lung capacity values than those with mild disease. There was an overall positive development of pulmonary outcomes from 3 to 12 months after hospital discharge. The discrepancy between the unaltered prevalence of self-reported dyspnoea and the improvement in pulmonary function underscores the complexity of dyspnoea as a prominent factor of long-COVID. The lack of increase in fibrotic-like findings from 3 to 12 months suggests that SARS-CoV-2 does not induce a progressive fibrotic process in the lungs.

A prospective study of pulmonary outcomes and chest CT the first year after COVID-19

COVID-19 primarily affects the respiratory system. We aimed to evaluate how pulmonary outcomes develop after COVID-19 by assessing participants from the first pandemic wave prospectively 3- and 12-months following hospital discharge. Pulmonary outcomes included self-reported dyspnoea assessed with the modified Medical Research Council dyspnoea scale (mMRC), 6-minute walking distance (6MWD), spirometry, diffusion capacity of the lungs for carbon monoxide (DLCO), body plethysmography, and chest computed tomography (CT). Chest CT was repeated at 12 months in participants with pathological findings at 3 months. The WHO ordinal scale for clinical improvement defined disease severity in the acute phase. Of 262 included COVID-19 patients, 245 (94%) and 222 (90%) participants attended the 3- and 12-month follow-up, respectively. Self-reported dyspnoea and 6MWD remained unchanged between the two time points, while DLCO and total lung capacity improved (0.28 mmol min−1 kPa−1, 95% CI (0.12–0.44), and 0.13 L, 95% CI (0.02–0.24), respectively). The prevalence of fibrotic-like findings on chest CT at 3 and 12 months in those with follow-up chest CT was unaltered. Those with more severe disease had worse dyspnoea, DLCO,å and TLC values than those with mild disease. There was an overall positive development of pulmonary outcomes from 3 to 12 months after hospital discharge. The discrepancy between the unaltered prevalence of self-reported dyspnoea and the improvement in pulmonary function underscores the complexity of dyspnoea as a prominent factor of long-COVID. The lack of increase in fibrotic-like findings from 3 to 12 months suggests that SARS-CoV-2 does not induce a progressive fibrotic process in the lungs. Even though an overall positive development of lung function was observed between 3 and 12 months after hospitalisation for COVID-19, the prevalence of dyspnoea and fibrotic CT-findings remained unaltered, independent of disease severity in the acute phase.