Abstract
Introduction: Bronchopulmonary dysplasia (BPD) is a risk factor for respiratory disease in children born preterm.
Aims: To extensively evaluate lung function in prematurely born adolescents with and without BPD in infancy and to assess change over time from school age.
Methods: Fifty-one individuals born between gestational weeks 24 to 31 in Stockholm, Sweden, were examined in adolescence (12-15 years of age) using spirometry, impulse oscillometry, plethysmography, multiple breath wash-out and ergospirometry. Comparison with spirometry and impulse oscillometry data from school age (6-8 years of age) was also made. Twenty-three infants were diagnosed with respiratory distress syndrome but not BPD, while 28 were graded as mild (n=17), moderate (n=7) and severe (n=4) BPD.
Results: Adolescents with a history of BPD, had lower forced expiratory volume in 1 sec (-0.80 vs. -0.02 z-scores, p <0.05), higher frequency dependence of resistance, R5-20, (0.11 vs. 0.063 kPa/L/s, p <0.05) and higher lung clearance index (9.6 vs. 7.1, p<0.05) compared to those without BPD.Between school age and adolescence, FEV1/FVC z-scores decreased for all groups, especially in the group with severe BPD (-2.95 z-scores, 95%CI -3.42;-1.42 at 12-15 years). Conclusions: Lung function reflecting the central and the peripheral airways were affected in adolescents previously diagnosed with BPD. The further reduction of the FEV1/FVC-ratio over time in the group with severe BPD might implicate a route towards chronic airway obstruction. Our results suggest the need for follow up of lung function in adulthood.
- Copyright ©the authors 2016
