Background: The term brief resolved unexplained events (BRUE) is a description of the acute event occurring in infants less than 1-year-old that includes at least one of the following characteristics: cyanosis or pallor; absent, decreased, or irregular breathing; marked change in tone or altered level of responsiveness. An investigative proceeding is required to identify the triggering phenomenon in those who are at high risk of complications. Prolonged esophageal pHmetry has been used as a tool in searching for gastroesophageal reflux disease (GERD) as one of the underlying etiologies.
Objective: The study aims to verify the frequency of GERD in infants up to 1-year-old, when pHmetry has been performed for investigating high-risk BRUE (HR-BRUE) and to analyze if clinical characteristics or any particular symptom related by caregivers during BRUE could be correlated to GERD.
Methods: It was performed a cross-sectional study. The data was collected retrospectively of patients less than 1-year-old, who had performed pHmetry in a tertiary hospital for investigating HR-BRUE between October 2008 and January 2018. For the analysis of medical records, a data collection protocol included: gender, age at the first HR-BRUE episode, age at the time of the pHmetry, gestational age, type of delivery (normal or caesarean) and birth weight and symptoms associated to HR-BRUE related by caregivers. Relation between variables were assessed using Fisher's exact test and Mann-Whitney test. The significance level was set at 0.05.
Results: A total of 54 infants were included (preterm 25, term 29), 62.9% males, median age at the HR-BRUE was 36 days, 53.7% HR-BRUE episodes had occurred during or right after feeding. According to pHmetry results: nine pHmetry results were considered inconclusive, physiological reflux (n=30) and GERD (n=15). The frequency of GERD diagnosed by pHmetry was 33%. GERD was not statistically related to gender (P-value=0.757), age at first HR-BRUE episode (P-value=0.960), age at the time of the pHmetry (P-value=0.720), prematurity (P-value=0.120) or type of delivery (P-value=0.738). GERD was statistically related to low birth weight (P-value=0.023). There was no association between symptoms reported by caregivers during HR-BRUE and GERD.
Conclusion: GERD diagnosed by the pHmetry was found in one third of infants that experiencing a HR-BRUE, showing the importance of properly investigation. In half of infants BRUE occurred during or right after feeding. Besides low birth weight, it was not possible to select other data from the clinical history that suggest that these patients would be more likely to have GERD.