Gastroesophageal reflux in infants < 32 weeks gestational age at birth: lack of relationship to chronic lung disease.

The objective of this study was to determine the incidence of gastroesophageal reflux (GER) as documented by extended esophageal pH monitoring in symptomatic premature infants and to identify its relationship with chronic lung disease (CLD). This was a retrospective study of 629 infants born < 32 weeks gestational age and admitted to the neonatal intensive care unit during the study period. Univariate analyses were done on the 137 infants undergoing the test for the association of the following risk factors with acid reflux: birth weight, gestational age, race, sex, length of stay, bronchopulmonary dysplasia (BPD; O2 requirement at 28 days), and severe CLD (O2 requirement at 36 weeks postmenstrual age). Eighty-seven of 137 infants were positive for GER. There was no association of GER with the risk factors studied, nor were there correlations with BPD or severe CLD. GER is common (63%) in premature infants < 32 weeks gestational age but clinical symptoms and CLD are poorly correlated with this diagnosis.