Symptoms Associated with Hypersensitivity to Gastric Distention in Functional Dyspepsia
Abstract & Commentary
Synopsis: Hypersensitivity to gastric distention is present in a subset of dyspeptic patients, and this finding will ultimately affect the diagnosis of such patients as well as provide a rationale for more effective therapy.
Source: Tack J, et al. Gastroenterology. 2001;121:526-535.
Functional dyspepsia is a syndrome that includes chronic upper abdominal discomfort with no anatomic basis. Eating frequently provokes dyspeptic symptoms that may entail epigastric pain or burning, bloating, early satiety, eructations, nausea, and vomiting. Many speculations exist regarding potential pathophysiology for dyspepsia including Helicobacter pylori infection, gastric and/or intestinal motor abnormalities, central nervous system dysfunction, and visceral hypersensitivity. Previous studies have demonstrated sensitivity to gastric distention in many dyspeptic patients, but there has been no certainty that these findings were related to symptom etiology. This study evaluated 80 healthy controls and 160 patients with functional dyspepsia (symptomatic for at least 12 weeks in the last 12 months). No anatomic basis for dyspepsia was present in the patients, and esophageal acid exposure was normal. A distending balloon capable of measuring pressures and compliance was used to distend the stomach in all participants. Gastric emptying studies were performed with a 14C octanoic acid breath test. Results indicated that dyspeptic patients were more sensitive to distention than the controls, and accommodation to the distending balloon was less in patients. It was found that 37% of all dyspeptic patients studied were hypersensitive. Symptoms associated with documented hypersensitivity included postprandial pain, belching, and weight loss.
Comment by Malcolm Robinson, MD, FACP, FACG
Dyspepsia can be a difficult clinical problem. It is extremely difficult to know exactly how aggressive we should be with diagnosis, and guidelines for therapy have been similarly obscure. Understanding the basis for any illness seems important for refining diagnoses and for selection of optimal therapy. This study, elegantly performed by the superb team of Tack and colleagues in Leuven, Belgium, helps us to understand dyspepsia in a significant subset of patients. For individuals with this type of dyspepsia, therapy should undoubtedly be focused on lessening the hypersensitivity present. Promotility agents and acid inhibitors would not be helpful in these patients, and we currently might try tricyclic and other antidepressants and perhaps the next generation of 5HT3 antagonists similar to the recently released and withdrawn alosetron will also provide relief for these troubled patients and their physicians.
Dr. Robinson, Medical Director, Oklahoma Foundation for Digestive Research; Clinical Professor of Medicine, University of Oklahoma College of Medicine Oklahoma City, OK, is Associate Editor of Internal Medicine Alert.