Abdominothoracic Muscular Tone in Functional Dyspepsia

Background. Patients with functional dyspepsia report symptoms after eating without detectable cause. A recent proof-of-concept study demonstrated that in healthy subjects, the activity of the abdominal walls influences perception of digestive sensations, specifically, intentional abdominal distension (by a maneuver of diaphragmatic contraction) increased bloating sensation in response to a probe meal.

Aim. To determine the role of the abdominothoracic muscular activity on symptoms of functional dyspepsia.

Design. Parallel study in dyspeptic patients who have an abnormal somatic response to a probe meal (experimental group), and patients who do not (control group), comparing the effect of abdominophrenic biofeedback on dyspeptic symptoms. The probe meal will consist in stepwise ingestion of a comfort meal (hot ham and cheese sandwich plus orange juice) up to maximal satiation.

Intervention. A standard biofeedback technique (3 sessions over a 4-week period) directed at controlling the muscular activity (postural tone) of the abdominal walls, will serve as active intervention in the experimental group, and as a sham intervention in the control (active comparator) group.

The study outcomes will be measured before, immediately after and at 6 months after biofeedback: 1) Clinical symptoms measured by scales during 7 consecutive days. 2) Responses to the probe meal: (a) sensations measured by scales; (b) changes in girth by adaptive belts; (c) diaphragmatic position by abdominal ultrasound.

Relevance. The identification of a pathophysiological mechanism of dyspeptic symptoms could serve as an objective marker for diagnosis and as a target for the development of mechanistic treatments.