Bronchopulmonary dysplasia and very low birthweight: Lung function at 11 years of age

Objective: To determine the relationship between lung function at 11 years of age and bronchopulmonary dysplasia (BPD) in very low birthweight (VLBW) children. Methodology: This study comprised 154 consecutive surviving VLBW children, divided into three groups with respect to their neonatal respiratory morbidity: group I developed BPD; group II required assisted ventilation but did not develop BPD; and group III required no assisted ventilation. Lung function tests were measured on 120/154 (77.9%) children at II years of age. The relationship between various lung function variables and neonatal lung disease was analysed by multiple linear regression. Results: Several lung function variables reflecting airflow were significantly diminished in the BPD group (n = 15), and residual volume was significantly higher. Despite poorer lung function overall, few children in the BPD group had lung function abnormalities in the clinically significant range (n = 2 [13.3%] with a forced expired volume in 1 s < 75% predicted; n = 2 [13.3%] with a forced vital capacity < 75% predicted; n = 1 [6.7%] with a residual volume/total lung capacity > 35%). There were no significant differences in lung function variables between group II (n = 41) and group III (n = 64). Changes in lung function tests between 8 and 11 years did not vary significantly between the three groups. Conclusions: VLBW children with BPD in the newborn period have poorer lung function at II years of age than other surviving VLBW children without BPD, although few have lung function abnormalities in the clinically significant range.