BACKGROUND AND AIM:Little is known about the relation between gastroesophageal reflux (GER) episodes and sleep interruptions in infants. The aim of the study was to evaluate the relationship between GER and the incidence of sleep interruptions in infants. METHODS:Study patients included 24 infants (younger than 1 year) referred for multichannel intraluminal impedance and esophageal pH monitoring with simultaneous polysomnography. Exclusion criteria were a previous fundoplication and studies lasting <20 hours. Tests were clinically indicated to investigate suspicion of GER-related apnea (17, 70.8%), stridor (6, 25%), noisy breathing (2, 8.3%), and cyanotic spells (1, 4.2%). Most patients presented with significant comorbidities (19, 79.2%). RESULTS:The number of nonacid GER (NAGER) per hour was greater during sleep time than during daytime and awakening following sleep onset (median 0.27 vs 1.85 and 1.45, P<0.01). A total of 1204 (range 7-86 per infant) arousals in 24 infants was detected, 165 (13.7%) that followed GER episodes, and 43 (3.6%) that preceded GER episodes. Seven patients presented with a positive symptom association probability for arousals; 5 were exclusively because of NAGER. A positive symptom association probability for awakenings was detected in 9 patients; 4 were because of NAGER, 4 were because of AGER, and 1 was because of both NAGER and GER. Patients with awakenings related to GER presented longer mean clearance time of AGER during sleep (165.5 vs 92.8 seconds, P=0.03). CONCLUSIONS:GER was a frequent cause of interrupting sleep among our infant patients, and NAGER proved to be equally important as AGER for causing arousals and awakenings in infants.