Characterizing Nighttime Acid Reflux in Children - Abstract
Background: In adults, it has been demonstrated that nighttime gastroesophageal reflux (GER) occurs primarily in the first half of sleep. It is unknown if the same reflux pattern occurs in children with GER.
Objective: To characterize the association between age and GER symptoms with the frequency and severity of nighttime GER in children.
Study Design: Esophageal pH monitoring studies performed in 135 symptomatic children were analyzed retrospectively. Children were divided into 3 age groups: Children <1 year of age, children between 1 and 3 years of age, and children greater than 3 years of age. Nighttime was defined as the period from 6 pm to 6 am, and sub-divided into early and late nighttime (6 pm to 12 midnight, 12 midnight to 6 am, respectively). The total number of acid reflux episodes, reflux index (RI), and esophageal acid clearance time (AC) was monitored and compared between different periods throughout the monitoring period. We also examined the association between clinical symptoms of acid reflux and objective measures of GER severity.
Results: Children <3 years of age had a higher frequency of acid reflux during the daytime (63.5 versus 33.0, p<0.01), nighttime (46.0 versus 19.0, p<0.01), early nighttime (29.0 versus 13.0, p<0.01) and late nighttime (14.5 versus 2.0, p<0.01) compared to children ?3 years of age. Children less than 1 year of age had similar acid reflux episodes during the early and late-night, whereas children 1-3 and ?3 years of age had more frequent early nighttime acid reflux than late nighttime acid reflux. We found no consistent association between clinical symptoms and severity of acid reflux, other than a higher frequency of acid reflux episodes among children with complaints of vomiting.
Conclusions: There are a significantly more episodes of nighttime GER among children <3 years of age compared to children ?3 years of age, and more frequent acid reflux during the early nighttime compared to the late nighttime only among children ?3 years of age. This may be a result of more frequent nighttime feeding among younger children and infants. We also found that the RI and AC were not significantly different between the early and late nighttime periods among all patient age groups, which contrast with data from adult studies.