Dietary influence on electrogastrography and association of alterations in gastric myoelectrical activity with symptoms in patients with functional dyspepsia

Background and Aim: It is unclear which type of meal is adequate in measuring electrogastrography and which parameter of electrogastrography is of clinical relevance. The aims of the present study were to compare the influence of water and a nutrient drink on electrogastrography in patients with functional dyspepsia (FD) and in healthy volunteers, and to investigate the association of alterations of electrogastrography with symptoms. Method: In 30 patients with FD and 12 healthy volunteers, the recording of electrogastrography with symptom assessments was performed preprandially and postprandially. Subjects ingested the same volume of water and a nutrient drink at a fixed rate, which was performed in a randomized cross-over design. Results: Unlike water, the power ratio after/before a nutrient drink was significantly lower in patients compared to controls. Patients had more severe bloating and epigastric pain after nutrient ingestion than after water intake. Absent postprandial increase of power was observed in seven of the 30 patients after nutrient intake, and in three of the 30 patients after water intake. The former patients had significantly more severe fullness and bloating. Irrespective of a test meal, the percentage rates of normogastria significantly decreased postprandially in the patient group, but not in the control group. No differences in symptom severity were observed between patients with and without abnormally low percentage rates of normogastria. Conclusions: Decreased postprandial rates of normogastria and absent postprandial increase of power are electrogastrographic abnormalities found in a subset of patients with FD. A nutrient drink is more adequate for the detection of such alterations than water. The lack of a postprandial increase of power is associated with the severity of some dyspeptic symptoms, but decreased postprandial rates of normogastria are not.