380 - Oxygen Requirement– vs Respiratory Support–Based BPD Classification at 36 Weeks PMA: Associations with School-Age Pulmonary Function

Publication Number: 1364.380

Jihye Yoon, Seoul national university, Jongrogu, Seoul-t'ukpyolsi, Republic of Korea; Ji Soo Park, Seoul National University Hospital, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Seung Han Shin, Seoul National University Children's Hospital, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Dong In Suh, Seoul National University Hospital, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Han-Suk Kim, Seoul National University Children's Hospital, Jongno-Gu, Seoul-t'ukpyolsi, Republic of Korea; Ee-Kyung Kim, Seoul National University Children's Hospital, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Ju Sun Heo, Seoul National University College of Medicine, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Seh Hyun Kim, Seoul National University Children’s Hospital, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Baek Sup Shin, Seoul National University Children's Hospital, Jongno-gu, Seoul-t'ukpyolsi, Republic of Korea; Gyeong Eun Yeom, Seoul National University Children's Hospitsl, Seoul, Seoul-t'ukpyolsi, Republic of Korea; Dabin Kim, Seoul Nationl University, Seoul, Seoul-t'ukpyolsi, Republic of Korea

Background: With rising survival rates of extremely preterm infants, accurate diagnosis of bronchopulmonary dysplasia (BPD) is increasingly important. The 2001 NIH definition is based on oxygen use at 36 weeks PMA, while the 2019 Jensen classification focuses on the mode of respiratory support. The optimal predictor for long-term pulmonary outcomes remains uncertain

Objective: This study compares the predictive value of both definitions for school-age pulmonary function and aims to determine the optimal predictors for long-term outcomes.

Design/Methods: This cohort included preterm infants ( < 32 weeks GA or < 1500 g) admitted to Seoul National University Hospital (2013–2017). Of 100 eligible infants, 72 completed spirometry at school age. BPD severity was classified using both NIH 2001 and Jensen 2019 criteria. Pulmonary function test (PFT) z-scores were derived from GLI equations. Clinical data were analyzed with Kruskal-Wallis, Mann-Whitney, and multivariate logistic regression tests.

Results: This study included 72 preterm infants with a median gestational age of 27.9 weeks [IQR 26.1, 29.7] and a median birth weight of 940 g (IQR 717.5, 1140.0] , including 37 male patients (51.4%). FEV₁/FVC z-scores by the oxygen-based 36-week definition were −1.063 [−1.998, 0.617] in the no–mild group (n=41) and −1.195 [−1.945, −0.158] in the moderate–severe group (n=31). By the respiratory-support–based 36-week definition, medians were −0.979 [−1.920, 0.400] for grades 0–1 (n=55) and −1.673 [−2.343, −0.368] for grades 2–3 (n=17). Although groupwise differences across 4 severity levels were not significant in most PFT z-scores, a trend toward lower FEV₁/FVC z-scores was observed in grades 2–3 (rank-sum p=0.076). Defining abnormal pulmonary function as an FEV₁/FVC z-score < −1.64, BPD grades 2–3 by the Jensen definition were associated with increased odds of abnormal function (aOR, 4.37; 95% CI, 1.19–15.97) after adjustment for gestational-age group, SGA status, and sex, whereas moderate-to-severe BPD by the 2001 NIH definition showed no significant association. However after adjusting for gestational age < 28 weeks, SGA status, and sex, moderate-to-severe BPD defined by the Jensen classification was significantly associated with an increased likelihood of abnormal lung function (OR, 4.37; 95% CI, 1.19–15.97; p=0.026), whereas 2001 NIH definition showed no such significant association.

Conclusion(s): These findings suggest that the Jensen classification may better predict airflow limitation at school age compared with the NIH definition in this cohort.