Rumination syndrome, or merycism, is a chronic motility disorder characterized by effortless regurgitation of most meals following consumption, due to the involuntary contraction of the muscles around the abdomen. There is no retching, nausea, heartburn, odour, or abdominal pain associated with the regurgitation, as there is with typical vomiting, and the regurgitated food is undigested. The disorder has been historically documented as affecting only infants, young children, and people with cognitive disabilities (the prevalence is as high as 10% in institutionalized patients with various mental disabilities). It is increasingly being diagnosed in a greater number of otherwise healthy adolescents and adults, though there is a lack of awareness of the condition by doctors, patients and the general public. Rumination syndrome presents itself in a variety of ways, with especially high contrast existing between the presentation of the typical adult patient without a mental disability and the presentation of an adult with a mental disability. Like related gastrointestinal disorders, rumination can adversely affect normal functioning and the social lives of individuals. It has been linked with depression. Little comprehensive data regarding rumination syndrome in otherwise healthy individuals exists because most people are private about their illness and are often misdiagnosed due to the number of symptoms and the clinical similarities between rumination syndrome and other disorders of the stomach and esophagus, such as gastroparesis and bulimia nervosa. These symptoms include the acid-induced erosion of the esophagus and enamel, halitosis, malnutrition, severe weight loss and an unquenchable appetite.
Breathing in this method works by physically preventing the abdominal contractions required to expel stomach contents. Supportive therapy and diaphragmatic breathing has shown to cause improvement in 56% of cases, and total cessation of symptoms in an additional 30% in one study of 54 adolescent patients who were followed up 10 months after initial treatments. Patients who successfully use the technique often notice an immediate change in health for the better. Individuals who have had bulimia or who intentionally induced vomiting in the past have a reduced chance for improvement due to the reinforced behavior. The technique is not used with infants or young children due to the complex timing and concentration required for it to be successful. Most infants grow out of the disorder within a year or with aversive training. Epidemiology
Rumination disorder was initially documented
as affecting newborns,
infants, children
and individuals with mental and functional disabilities (cognitively disabled). It has since been recognized to occur in both males and females of all ages and cognitive abilities.Among cognitively disabled people, it is described with almost equal prevalence among infants (6–10% of the population) and institutionalized adults (8–10%). In infants, it typically occurs within the first 3–12 months of age.The occurrence of rumination syndrome within the general population has not been defined. Rumination is sometimes described as rare, but has also been described as not rare, but rather rarely recognized. The disorder has a female predominance.