Longitudinal post-discharge growth according to bronchopulmonary dysplasia severity in very preterm infants: a cohort study.

To evaluate the association between bronchopulmonary dysplasia (BPD) severity and post-discharge growth during the first year of corrected age in very preterm infants, including recovery from established growth failure at hospital discharge. This retrospective cohort included 1,106 infants born before 32 weeks' gestation, classified using the Jensen BPD definition as no BPD (n = 768), mild (n = 142), moderate (n = 154), or severe BPD (n = 42). Weight, length, and head circumference z-scores were assessed from birth to 12 months corrected age. Longitudinal growth trajectories and time to recovery from discharge growth failure were evaluated using adjusted models. Increasing BPD severity was associated with progressively poorer anthropometric outcomes at discharge and 12 months (all p < 0.001). At 12 months, severe BPD remained independently associated with lower weight (β - 0.596, 95% CI - 1.134 to - 0.057; p = 0.030), length (β - 0.800, 95% CI - 1.443 to - 0.156; p = 0.015), and head circumference (β - 1.177, 95% CI - 2.001 to - 0.353; p = 0.005) z-scores. Among infants with growth failure at discharge, severe BPD was associated with slower recovery of weight (HR 0.40, 95% CI 0.19-0.81; p = 0.011), length (HR 0.25, 95% CI 0.14-0.48; p < 0.001), and head circumference (HR 0.23, 95% CI 0.08-0.72; p = 0.012). Median recovery was not reached for any anthropometric domain in severe BPD; corresponding 12-month recovery probabilities were 41.3%, 42.6%, and 30.1%, respectively. Conclusion: Severe BPD was independently associated with persistent impairment in weight, length, and head circumference and substantially delayed recovery from established growth failure during infancy. These findings support structured longitudinal growth monitoring and targeted nutritional follow-up after discharge.