A Novel Biofeedback Treatment to Offset Abdominal Distention

 I'm Dr David Johnson, professor of medicine and chief of gastroenterology at Eastern Virginia Medical School in Norfolk, Virginia. 

The bothersome and sometimes profound symptoms of abdominal bloating and distention are quite prevalent. 

In the general population, about 1 in 7 persons experience symptoms of bloating each week. 

It's important to delineate bloating from distention. Distention is an objective and visible increase in the abdominal girth. I've had patients come in with pictures where postprandially, they suddenly look like they're extremely pregnant. Bloating, however, is a gaseous sensation. 

Patients can describe having one or the other, yet they're not mutually exclusive. In fact, approximately 50% of patients with bloating also have abdominal distention. 

These symptoms occur more often with disorders of the brain-gut interaction, such as functional constipation, irritable bowel syndrome, and functional dyspepsia. 

When working on a differential diagnosis, an astute clinician will want to consider and exclude other potential causes of postprandial distention beyond those this discussion will focus on, such as malabsorption, maldigestion, celiac disease, dysbiosis, and insufficiency or motility disorders. 

Abdominophrenic Dyssynergia 

During normal circumstances, intraluminal ingestion triggers distention, particularly in the stomach but in the small intestine as well. In turn, this initiates a series of events leading to relaxation and ascension of the diaphragm. Basically, the abdominal cavity is made larger to accommodate the distention related to the ingestion, with a concomitant reflex contraction of the abdominal muscles to limit any of that distention-related consequence of abdominal girth. This is a physiologic event called "abdominal accommodation," which provides a built-in way to protect against distention.

When this process is disjointed, there's a maladaptive response called "abdominophrenic dyssynergia." In abdominophrenic dyssynergia, an abnormal somatic response occurs, which causes paradoxical contraction of the chest and abdominal walls that results in abdominal distention and is frequently triggered by a sensation of bloating. 

This can be quite dramatic. It typically occurs postprandially, with the peak event of maximal distention setting in approximately 45 minutes after a meal.

Biofeedback Approach for Distention

Recently, results were published from a randomized controlled trial conducted in Spain, in which investigators validated a biofeedback procedure for treating abdominal distention. 

Investigators enrolled patients with visible abdominal distention following meal ingestion. They excluded patients with other common causes of distention. Eligible patients were not constipated.

A group of 42 patients (38 women and six men) were randomized to receive the biofeedback technique or placebo (ingestion of a capsule before breakfast, lunch, and dinner). All participating women were in the follicular phase of their menstrual cycle, meaning between 5 and 15 days after the onset of their last menstrual period. Patients were not allowed to be on any type of neuromodulators or have a history of psychiatric comorbidity or psychotropic treatment. 

In the biofeedback group, patients were trained during three separate sessions over 4 weeks. Abdominal plethysmography using adaptable belts was used, with the results shown to the patients to teach them how to effectively mobilize their diaphragm by contraction (chest down, abdomen out) and relaxation (chest up, abdomen in). Over a 6-month follow-up period, patients were requested to perform biofeedback exercises at home 5 minutes before and 5 minutes after breakfast, lunch, and dinner.

At the end of the 4-week training interval, there was dramatic response to an offending meal. Only one patient in the biofeedback group did not respond. Intercostal activity decreased by a mean of 82%, and clinical symptoms improved by a mean of 66%. 

At the end of the 4-week period, patients receiving placebo were allowed to cross over and receive biofeedback training. Similar to results in the treatment arm, all but one of those patients responded; one patient was lost to follow-up. 

Improvements following biofeedback treatment in both groups were maintained at 6-month follow-up, indicating what seems to be very durable effects. There was really no downside to the biofeedback treatment. 

Overall, I think this is a provocative study. Even though it was performed using complex plethysmography and required special training, it offers a very easy technique to use. 

A Different Approach to Diaphragmatic Breathing

It should be noted that the training was done in a very different manner to diaphragmatic breathing, which I've described in a previous video. In this process, which I call "belly breathing," the chest stays in, your abdomen goes out, and you relax the abdominal muscles. That's important to differentiate when we start to talk about this with our patients. 

Some of us have tried diaphragmatic breathing for abdominophrenic dyssynergia, with mixed results. However, with the biofeedback technique described in this study, I think we now have a much more direct approach. 

Abdominophrenic dyssynergia is also different from the conditions we would treat with diaphragmatic breathing, which would include things like rumination syndrome — for which this is pretty much the first approach you'd consider — singultus (hiccups), and chronic belching. I've had excellent success using diaphragmatic breathing in those conditions. 

But again, the approach outlined in this new study is different. It's simple and easy to teach your patients. To help you learn it, the authors helpfully provided an instructional video supplementary to their article, which I would invite you all to take a look at. 

This is a simple thing we can use in brain-gut disorders causing abdominophrenic dyssynergia, but nonetheless, its results may be revolutionary. 

Certainly, it's way overdue, and quite welcome that we now have something that we can recommend with strong supporting evidence. Although additional studies are needed to corroborate this, I see no downside to start considering this for your patients right now.

I'm Dr David Johnson. Thanks for listening.

David A. Johnson, MD, a regular contributor to Medscape, is professor of medicine and chief of gastroenterology at Eastern Virginia Medical School in Norfolk, Virginia, and a past president of the American College of Gastroenterology. His primary focus is the clinical practice of gastroenterology. He has published extensively in the internal medicine/gastroenterology literature, with principal research interests in esophageal and colon disease, and more recently in sleep and microbiome effects on gastrointestinal health and disease. 

https://www.medscape.com/viewarticle/novel-biofeedback-treatment-offset-abdominal-distention-2024a1000fuq