Air swallowing in Rett syndrome

Abstract

The possible causes of excessive swallowing of air leading to bloating, which is common in Rett syndrome (RS), were investigated during feeding and at rest. Seven individuals with RS aged between 4 and 33 years (three with air bloat) underwent feeding videoflouroscopy and concurrent respiration monitoring. The results were compared with a randomly selected group of 11 individuals, aged between 2 and 16 years, with quadriplegic cerebral palsy and feeding problems, some of whom had mild air bloat. All individuals from both groups had isolated pharyngeal swallows and several mouth breathed; this may account for some air swallowing but not the severe air bloat characteristic of RS. Thirty-three individuals with RS aged between 3 and 44 years were monitored for nasal respiration, chest movements, swallowing, and vocal cord position at rest (between feeding). Twenty had air bloat, 17 of whom swallowed air during breath-holding in the same way, and three gulped air during hyperventilation. Of the 13 without air bloat, eight did not have recurrent breath-holding and five did, but without concurrent air swallowing. Several methods for reducing air swallowing in apnoea were investigated. The most successful was a dummy with an air leak, but this was poorly tolerated and could only be used for short periods of time. Apnoeas and air bloat are often worse when individuals are distressed and may in some individuals be reduced by anxiolytic medications.

Autonomic breathing abnormalities in Rett syndrome: caregiver perspectives in an international database study

“…This differential between parent-report studies and clinical studies may in part result from the small sample size of the clinical studies ( n  < 48) [9, 10, 15, 29] or because some breathing irregularities are very subtle and thus not observable by family members or carers. By contrast, the proportion of patients with Rett syndrome reported with abdominal bloating in a small clinical study ( n  = 33, 61%) [31] was broadly comparable to the prevalence found in this parent-report study (42.2%). Ours is the largest genetically confirmed sample to compare the individual prevalences of breath-holding, hyperventilation and abdominal bloating across all age groups, giving strength to the findings.…”

“…We also found that abdominal bloating commonly co-occurred with both hyperventilation and breath-holding. Consistently, a study ( n  = 33) monitoring respiration and swallowing at rest determined that air swallowing could occur concurrently with both breath-holding and hyperventilation [31]. Of the 20 individuals with abdominal bloating, 17 swallowed air during breath-holding and the remaining three “gulped” air during hyperventilation.…”

“…In a population-based study on outcomes following gastrostomy, 39 of 66 with a gastrostomy also experienced abdominal bloating and 55% of those caregivers observed reduced impact following gastrostomy [41]. Abdominal bloating can be extremely uncomfortable, and gastrostomy has also been recommended in individual cases for venting and relief of pain [31, 32, 41]. Girls and women with a p.Arg294* mutation were perceived to be substantially affected by autonomic disturbances more often than girls and women in any other mutation group.…”

“…Abdominal bloating is thought to be related to the autonomic dysfunction and associated air swallowing in Rett syndrome [31, 32]. It is reported to affect between 50 and 60% of individuals with Rett syndrome [7, 27, 31].…”

“…It is reported to affect between 50 and 60% of individuals with Rett syndrome [7, 27, 31]. Although abdominal bloating is believed to be associated with pain and discomfort [32], these symptoms do not appear to be consistently reported by caregivers [32].…”