Structural abnormalities do not explain the reduced exercise capacity in preterm children

Background: Children born preterm have a reduced exercise capacity and structural lung disease. Aim: To identify the effect of structural lung disease on the exercise response in children aged 9-11, who were born preterm. Methods: Preterm children ( Results: Abnormalities on HRCT were noted in 68/78 (87 %) children. The most common abnormalities were linear subpleural triangular opacities (82 %), decreased pulmonary attenuation on expiration (40 %) and peribronchial thickening (38 %). Subpleural linear triangular opacities were associated with an increased peak (45.7 +/-6.98) vs. 40.05 +/-6.29 ml/kh/min; p=0.011), peak tidal volume (25.1 +/-4.72 vs. 21.8 +/-5.33 mL/kg; p=0.014 and peak minute ventilation (1.45 +/-0.3 vs. 1.22 +/-0.1 L/kg. p=0.02). The presence of peribronchial thickening was associated with increased incidence of dynamic flow limitation (40 % vs. 15 %, p=0.027), change in end expiratory lung volume at peak exercise (62.9 +/-216 vs. -97 +/-299 mL, p=0.023) and an increased tidal volume at peak exercise (26.5 +/-5.3 vs. 23.4 +/-4.3 mL/kg, p=0.018). Decreased pulmonary attenuation on expiration was not associated with any changes in exercise outcomes. Conclusion: In this study, structural lung disease was common in preterm children. The presence of structural lung damage was associated with dynamic flow limitation and gas trapping during exercise but did not contribute to a reduced exercise capacity.