BPD in association to lung function at school age
At 12 years of age, children born very preterm with a former diagnosis of BPD had more airflow obstruction, higher airway resistance and a lower diffusion capacity than preterm infants without BPD (Tables 2 and 3, and Figure 1).
More airway obstruction was read as a lower FEV1/FVC and FEF25-75 in children with than in children without BPD (p=0.022 and p=0.021, respectively), but there was no difference in FEV1, FVC, or in static volumes. However, the dysanapsis ratio were lower in children with than in children without BPD (p=0.023, Table 2).
Children with a history of BPD had an increased peripheral resistance (measured as R5-R20 and R5-R20 % of predicted by IOS) compared to children born without BPD. The higher airway resistance in children born preterm versus term was mainly explained by specifically higher resistance among children with BPD.
Diffusion capacity was lower in children with BPD compared to children with no BPD, both as DLCO and DLCO % of predicted. The lower level of diffusion capacity in very preterm born children compared to term born was mainly explained by the lower values in children with BPD (Table 3).
Children with a history of BPD also had a larger ventilation inhomogeneity of the conductive airways, measured as Scond than in children without BPD. In addition, preterm-born children with a diagnosis of BPD, but not children without BPD, had worse LCI5.0, Scond and Sacin than children born at term (Table 3).