Supplementary Material for: Structural Pulmonary Abnormalities Still Evident in Schoolchildren with New Bronchopulmonary Dysplasia

Background: A new pattern of bronchopulmonary dysplasia (BPD) has emerged with the improved survival of preterm children. Objectives: Our aim was to characterize structural abnormalities associated with new BPD and to evaluate whether the severity of high-resolution computed tomography (HRCT) changes is associated with lung function. Methods: HRCT scans were performed on 21 schoolchildren with a history of new BPD (mild, n = 9; moderate, n = 4; and severe, n = 8) with a mean age of 12.7 years (range: 8.7-16.7). Scans were interpreted by 2 radiologists using a structured scoring system. Spirometry (forced expiratory volume in 1 s [FEV₁] and maximum mid-expiratory flow [MMEF]) and the diffusion capacity of the lung for carbon monoxide (DLCO) were measured. Results: At least 1 HRCT abnormality was evident in 17 children (81%), including linear-to-triangular subpleural opacities (71%), air trapping (29%), mosaic perfusion (24%), peribronchial thickening (14%), and emphysema (14%). The HRCT score was higher in the severe BPD group (11.50; 95% CI 2.86-20.14) than in the mild or moderate BPD group (1.39; 95% CI 0.24-2.54, and 2.75; 95% CI 0.28-5.22, respectively). HRCT scores were inversely related to FEV₁ (β -4.23; 95% CI -6.97 to -1.49, p = 0.004) and MMEF (β -3.45; 95% CI -6.10 to -0.80, p = 0.013) but not to DLCO. The duration of the initial mechanical ventilation was associated with HRCT scores (p = 0.014). Conclusions: Structural lung abnormalities are common among schoolchildren with a history of new BPD, resembling abnormalities described in the presurfactant era. HRCT abnormalities are associated with the duration of early mechanical ventilation and the severity of BPD and they are correlated with spirometry.