mise à jour du
1 mars 2009
Journal of Psychosomatic Research
Air swallowing as a tic
Rimona S. Weil, Andrea E. Cavanna
John M.T. Willoughby, Mary M. Robertson
Institute of Neurology, Queen Square, London, UK


A tic is a brief involuntary movement that can be suppressed by the individual but at the expense of mounting inner tension, often with subsequent rebound [11. Gilles de la Tourette syndrome (GTS) is a neurodevelopmental disorder characterized by multiple motor tics and one or more vocal tics that usually begin before the age of 18. Estimates of the prevalence of GTS vary. The generally accepted figure was 0.5/1000, but recent research suggests that between 1% and 3% of school children are affected. The nature and phenomenology of tics vary widely, even in documented familial cases. They may take the form of a movement, a vocalization (phonic tic), or a complex phenomenon such as an echophenomenon or coprolalia (the inappropriate.utterng of obscenities) which is a rare manifestation of GTS. Tics can be increased in conditions of stre$s, boredom, or fatigue. Patients often report that tics are preceded by distinct premonitory feelings or sensations, they are temporarily suppressible, and patients experience relief after the tic has occurred. Tics can also fluctuate in severity and change character within the same person.
It is increasingly recognized that tics can be unusual in their manifestations and even self-injurious with reports of teeth grinding, vomiting, and retching, and other selfinjurious behaviors.
Aerophagy is a pattern of repetitive air swallowing and troublesome belching that is objectively observed and has been present for the last 3 months with symptom onset at least 6 months before diagnosis. It may be undetected until the patient develops a distended abdomen. It is often associated with abdominal discomfort and distension and patients may present to gastroenterologists with pseudoobstruction or malabsorption, although life-threatening complications are rare. Aerophagy has been described as a cause of irritable bowel syndrome and is frequently reported in association with neurological disorders and learning disabilities, with a high incidence in institutionalized patients. In particular, it has been linked with Huntington's disease and Rett syndrome in which it is particularly common and is thought to be due to abnormal feeding patterns during feeding or to specific oropharyngeal problems. Adults with aerophagy have recently been shown to have an increased prevalence of anxiety, and anxiety per se has been linked to increased swallowing rates in normal subjects [18], which may suggest a possible precipitating factor in predisposed individuals. Zella et al. reported incessant "eructation" as the presenting symptom of obsessive-compulsive disorder, the latter being a comorbid psychopathology in 30-60% of patients with GTS. Aerophagy has also been described as a phenomenon in children with no neurological abnormalities.
Although air swallowing can be secondary to a surgical or interventional procedure, as in nasal intermittent positive pressure ventilation, and latyngectomy [231, usually no organic cause is found. The exact mechanism of air swallowing in aerophagy is not fully understood, but a recent study has shown that distraction and attention have a significant effect on belching in patients with aerophagia. This may provide some insight into a possible mechanism for air swallowing in GIS and also has important implications for behavioral therapy.
To the best of our knowledge, there have been very few reports of air swallowing as a tic in the literature, apart from one recent report of air swallowing in GIS leading to ileus. The lack of documentation of air swallowing as a tic may suggest that it is a rare phenomenon, but it is also likely that it is an unrecognized and underreported feature of GIS. We are therefore documenting this patient with air swallowing as a tic in GIS to highlight the importance of unusual features of GIS which may be amenable to treatment.
Case report
A 22-year-old man with mild learning disability was referred to the National Hospital for Neurology and Neurosurgery where he was diagnosed with GIS. The patient was assessed with the National Hospital Interview Schedule, the Yale Global Tic Severity Scale, the MOVES self-rating scale for GIS, and the burette Syndrome Diagnostic Confidence Index. The first tic that the patient exhibited took the form of barely audible muttering, a complex tic, at the age of 14. This was followed by a wide variety of tics. He had at least 47 motor tics including frowning, blinking, facial grimacing, and smelling things, as well as some complex movements such as hopping and skipping. He had at least 17 vocalization tics which included yawning, barking, snorting, and saying "yes" very loudly. He also had mental coprolalia, echolalia, palilalia, forced touching, aggression, and some obsessive compulsive behaviors. On the Yale Global Tic Severity Scale h scpred 48/55, and on the Diagnostic Confidence Index he scored 69%, suggesting that there was no doubt at all about the diagnosis and that he had GIS of moderate seventy. Family history of note included a maternal aunt with facial tics in childhood, lasting into adulthood. He had been prescribed clomipramine 85 mg daily since the age of 16 for depressive symptoms associated with his GIS. Treatment with clonidine had previously been attempted for his tics, but as it had no effect on them it was withdrawn.
At the age of 18, the patient presented with longstanding constipation and 5 weeks of bloating, abdominal distension, and repeated regurgitation associated with profuse belching.
This was relieved by the passage of flatus. He also had reduced appetite and had lost half a stone (3.2 kg) in weight. His parents had noticed the sounds of air swallowing. We enquired and it appeared that he was probably not able to suppress the air swallowing, but it was unclear if air swallowing increased in times of anxiety: his being learning disabled made the subjective history less clear.
On examination, the abdomen was distended and resonant to percussion. Bowel sounds were normal but continuous. Plain abdominal X-ray revealed a grossly distended stomach, air in the intestine but no mechanical obstruction. A small bowel meal, which followed the initial plain abdominal film by 1 week, was within normal limits, excluding a volvulus. Blood tests were normal and the patient was diagnosed with a "windy abdomen" due to air swallowing. The air swallowing and associated symptoms resolved spontaneously, within 7 weeks of onset.
The symptoms of abdominal distension and discomfort recurred more mildly 5 months later and resolved within 6 weeks, soon after stopping clomipramine. Although the gastrointestinal symptoms and air swallowing improved, other motor and vocal tics worsened and he was treated with sulpiride and paroxetine. He continued on these medications until he suffered a further relapse of air swallowing 3 years later. This was also milder than the initial episodes and associated with abdominal distension, but far less than on the earlier occasions. Supine abdominal X-ray showed generalized distension of the gastrointestinal tract. The distension resolved with conservative management. The patient has remained well on the same treatment for the past 7 years. He has had no further periods of air swallowing or abdominal distension. His motor and vocal tics are also well controlled and he has been able to work in a supermarket for the past 3 years.
This patient with GTS was noted to be swallowing air. The symptoms lasted longer than 12 weeks in total, but were not consecutive and so do not quite fulfil the latest diagnostic criteria for aerophagy [11, although he fulfils the previous diagnostic criteria. In this case, there were several possible causes for the air swallowing. Our patient was learning disabled, which has been linked to air swallowing. However, our patient was able to articulate the sensation of air swallowing and his parents gave a very clear description. It was felt overall that this was a tic rather than any other clinical phenomenon.
The patient was also taking clomipramine, which has been linked to aerophagy. However, that report only links tricyclic antidepressants with air swallowing caused by increased water consumption due to a dry mouth. This was not a feature of the presenting case, who was noted by his parents to be swallowing air at times both when he was and was not drinking fluids. Moreover, the patient had been stable on clomipramine for 2 years, without air swallowing, and the air swallowing resolved whilst he was still taking clomipramine. Other causes of air swallowing such as excessive talking whilst eating, drinking carbonated drinks, and rapid eating were ruled out as they were not present in this case. We thus suggest that this air swallowing may have been a tic.
There are three descriptions of possible air swallowing as a tic in the literature. The first is in the form of a debate in which an apparent sequence of hiccups was identified by the author as possible aerophagy as a tic. Alternative diagnoses were pharyngeal dystonia and branchial myoclonus. The second is in the Shapiro et al. series of patients with GTS where several demonstrated hiçcupping and one demonstrated belching as vocal tics, suggesting that air swallowing may have been previously associated with GTS.
More recently, Frye and Hait described a 16-year-old boy diagnosed with GTS at the age of 7, who developed clinically significant air swallowing over a 2-month perio& The air swallowing was paralleled by an acute increase in vocal tics and psychological stressors, and resulted in abdominal cramping, eructation, and flatus, eventually leading to "aeroenteria" and recurrent ileus. Of note, according to the authors the air swallowing resulted from the aggravation of already present tics, rather than representing a newly developed and isolated tic, as in our patient.
In most cases, air swallowing resolves spontaneously within weeks or months. Where symptoms persist, treatment may be difficult. Some groups have successfully used carbon tablets and others have attempted behavioral therapy with some success. However, in cases where air swallowing is suspected to be a tic, it could be treated pharmacologically, as for GTS, with neuroleptic drugs such as haloperidol, pimozide, and sulpiride [341, or the newer atypical antipsychotics risperidone and aripiprazole. Of these, risperidone could prove particularly useful in this context, since it is associated with fewer gastrointestinal side effects compared to aripiprazole.