Recurrent respiratory illnesses are frequent in infants following repair of esophageal atresia and functional abnormalities of respiratory and esophageal function are often seen in older children. Recurrent aspiration is a potential cause of these respiratory abnormalities, but a relationship between abnormalities of gastrointestinal and respiratory mechanics has not been adequately investigated. We sought an association between lower esophageal sphincter (LES) incompetence, gastroesophageal reflux (GER), and respiratory function abnormalities in 18 subjects (age 12 to 21 years) following repair of esophageal atresia (Vogt type 111B). In each subject, measurements were made of spirometry, lung volumes assessed by plethysmography, esophageal manometry recorded using a constantly infused fluid-filled trilumen catheter to assess LES pressure and esophageal motility, and esophageal pH monitoring to detect GER. Subjects were grouped according to the presence or absence of a radiologically supported diagnosis of pneumonia in the first 4 years of life. Lung volumes were mildly but significantly decreased in the "pneumonia" group compared with the "nonpneumonia" group. There was no association between abnormalities of respiratory function and abnormal LES pressure or the presence of GER. These data suggest that pneumonia in esophageal atresia infants is associated with mild long-term lung damage. LES dysfunction and GER do not appear to play a major role in this process.