Functional dyspepsia includes pain or burning in the epigastrium, early satiety, and fullness during or after a meal, without an organic cause. It affects 5 to 11% of the population. Suitable workup and treatment are summarized in this new review article.
Dyspepsia is a constellation of symptoms referable to the gastroduodenal region of the upper gastrointestinal tract. Functional dyspepsia, a relapsing and remitting disorder, is the most common cause of these symptoms.
• What are the diagnostic criteria for functional dyspepsia and how is it classified?
The Rome III criteria for functional dyspepsia consist of a sensation of pain or burning in the epigastrium, early satiety (inability to finish a normal-sized meal), fullness during or after a meal, or a combination of these symptoms. Symptoms must be chronic, occurring at least weekly and over a period of at least 6 months, in the absence of an organic explanation. In the past 10 years, the terminology used to describe functional dyspepsia has changed, moving away from grouping patients according to the predominant reported symptom as having ulcer-like, reflux-like, or dysmotility-like functional dyspepsia and instead describing them as having one of two newly defined syndromes, the epigastric pain syndrome and the postprandial distress syndrome. These two syndromes were proposed because as many as 80% of persons with dyspepsia report that their symptoms are aggravated by the ingestion of a meal.
• What is the role of upper gastrointestinal endoscopy in patients with dyspepsia?
Symptoms do not reliably distinguish between organic and functional forms of the disease, so the challenge for the physician evaluating a patient with dyspepsia lies in discriminating between functional dyspepsia and organic conditions of the stomach or duodenum that may provoke similar symptoms. Given that upper gastrointestinal endoscopy is associated with a relatively low rate of identification of organic disease, it is neither desirable nor realistic to perform this test in all patients with dyspepsia. Guidelines recommend that patients with dyspepsia who report so-called alarm symptoms (see Table 2), which may indicate an underlying gastroesophageal cancer, be referred urgently for upper gastrointestinal endoscopy. For patients with simple dyspepsia who do not have alarm symptoms, in whom the likeliest diagnosis is functional dyspepsia, the requirement for any further diagnostic testing depends on the background prevalence of Helicobacter pylori infection. In populations in which the prevalence of infection is at least 10%, noninvasive testing for H. pylori, with either carbon-13-labeled urea breath testing or stool antigen testing, is recommended. In practice, however, because it is unlikely that the physician will be aware of the local prevalence of H. pylori, it is reasonable to use one of these tests as a first-line strategy, given that the testing is neither invasive nor prohibitively expensive.
Morning Report Questions
Q: What mechanisms are thought to produce the symptoms of functional dyspepsia?
A: An overarching disease model postulates that, in genetically predisposed persons, an allergen or infection leads to antigen presentation, barrier disruption, immune activation, and a type 2 helper T-cell response in functional dyspepsia, in which eosinophils are recruited that degranulate in some patients. In some patients, this process can lead to tissue injury and symptoms, whereas in others eosinophils may be protective and promote healing. An inflamed duodenum may be sensitive to acid and induce reflex responses and cytokine release that alter gastroduodenal function and esult in meal-related symptoms.
Q: Is there any novel therapy for the treatment of functional dyspepsia?
A: A substantial proportion of patients with functional dyspepsia have abnormalities in gastric motility and fundal accommodation. Partly as a result of the lack of efficacy of existing prokinetic drugs, new agents have been developed and tested in recent years. Acotiamide is an acetylcholinesterase inhibitor that accelerates gastric emptying and enhances gastric accommodation. In a double-blind, placebo-controlled trial involving 897 patients with functional dyspepsia in Japan, symptoms improved in 52% of those ssigned to active therapy, as compared with 35% of those assigned to placebo (P<0.001). When the effect of acotiamide on individual dyspeptic symptoms was studied, significant improvements were identified in postprandial fullness, upper abdominal bloating, and early satiety but not in upper abdominal pain or discomfort. The drug has now been approved for the treatment of the postprandial distress syndrome in Japan, and phase 3 trials are ongoing in Western populations.