Characteristics and Prognostic Factors of Pulmonary Fibrosis After COVID-19 Pneumonia

Abstract

BackgroundFew is known about the long-term pulmonary sequelae after COVID-19 infection. Hence, the aim of this study is to characterize patients with persisting pulmonary sequelae at follow-up after hospitalization. We also aimed to explore clinical and radiological predictors of pulmonary fibrosis following COVID-19.MethodsTwo hundred and 20 consecutive patients were evaluated at 3–6 months after discharge with high-resolution computed tomography (HRCT) and categorized as recovered (REC) or not recovered (NOT-REC). Both HRCTs at hospitalization (HRCT0), when available, and HRCT1 during follow-up were analyzed semiquantitatively as follows: ground-glass opacities (alveolar score, AS), consolidations (CONS), and reticulations (interstitial score, IS).ResultsA total of 175/220 (80%) patients showed disease resolution at their initial radiological evaluation following discharge. NOT-REC patients (45/220; 20%) were mostly older men [66 (35–85) years vs. 56 (19–87); p = 0.03] with a longer in-hospital stay [16 (0–75) vs. 8 (1–52) days; p < 0.0001], and lower P/F at admission [233 (40–424) vs. 318 (33–543); p = 0.04]. Moreover, NOT-REC patients presented, at hospital admission, higher ALV [14 (0.0–62.0) vs. 4.4 (0.0–44.0); p = 0.0005], CONS [1.9 (0.0–26.0) vs. 0.4 (0.0–18.0); p = 0.0064], and IS [11.5 (0.0– 29.0) vs. 0.0 (0.0–22.0); p < 0.0001] compared to REC patients. On multivariate analysis, the presence of CONS and IS at HRCT0 was independent predictors of radiological sequelae at follow-up [OR 14.87 (95% CI: 1.25–175.8; p = 0.03) and 28.9 (95% CI: 2.17–386.6; p = 0.01, respectively)].ConclusionsIn our population, only twenty percent of patients showed persistent lung abnormalities at 6 months after hospitalization for COVID-19 pneumonia. These patients are predominantly older men with longer hospital stay. The presence of reticulations and consolidation on HRCT at hospital admission predicts the persistence of radiological abnormalities during follow-up.

Multidimensional 3-Month Follow-Up of Severe COVID-19: Airways beyond the Parenchyma in Symptomatic Patients

“…About half of the patients complained of respiratory symptoms at follow-up, and unlike what was assumed, we observed a discrepancy between respiratory symptom with lung volumes/alveolar-capillary diffusion and residual radiological parenchymal impairment. These findings were consistent with previous studies that observed only a weak correlation between post-COVID respiratory symptoms and functional-radiological parenchymal impairment at follow-up [ 13 , 14 , 15 ]. Indeed, there is still a lack of evidence regarding the mechanisms of post-COVID respiratory syndrome.…”

“…Several studies have analysed CT parenchymal imaging of patients hospitalized for COVID-19 in a short- and medium-term follow-ups [ 2 , 3 , 13 , 14 , 15 , 19 , 20 , 21 , 22 ]. The methodological differences of these previous studies make a direct comparison among data difficult.…”

Post–Coronavirus Disease 2019 Pulmonary Fibrosis: Wait or Needs Intervention

“…Several risk factors for post-COVID-19 pulmonary fibrosis associated with an individual and disease itself have been proposed in previous studies (Table 2). 6,7,11,12,14,16,[20][21][22][23][24] Alu median days from discharge to last follow-up: 9 day), fibrosis was observed in 44% of patients, and patients with fibrosis showed more frequent abnormal radiological features including interstitial thickening, air bronchogram, irregular interface, coarse reticular pattern, and parenchymal bands on worst CT images than those without fibrosis. 22 Although it is not known to be directly related to the development of fibrosis, cigarette smoking and alcohol consumption are potential risk factors for post-COVID-19 pulmonary fibrosis because of their association with the progression of severe pneumonia.…”

Case Report: Pirfenidone in the Treatment of Post-COVID-19 Pulmonary Fibrosis

“…The common pattern of pulmonary interstitial lesions, also known as post-COVID-19 pulmonary fibrosis or COVID-19 pulmonary fibrosis-like ( 7 ), were ground glass opacities (GGOs), ground-glass attenuation and reticular abnormalities ( 8 ). At the same time, chest imaging showed bilateral diffuse interstitial lung disease among patients who complicated acute respiratory distress syndrome (ARDS) during acute phase ( 9 ). Relatedly, these survivals suffered from more serious ‘Long COVID' ( 10 , 11 ), a condition described by signs and symptoms of COVID-19 that last longer than 12 weeks and are not explained by an alternative diagnosis, with the most common symptoms of dyspnea, fatigue and ‘brain fog'.…”