This is general health information only and is not a substitute for advice from your GP or healthcare professional.
1. What is abdominophrenic dyssynergia?
Abdominophrenic dyssynergia is an abnormal coordination between the diaphragm and abdominal wall muscles that can contribute to visible abdominal distension. Instead of the abdominal wall relaxing and the diaphragm responding appropriately when intestinal contents increase, the diaphragm may contract downward while the abdominal wall relaxes, causing the abdomen to protrude.
2. Is abdominophrenic dyssynergia the same as bloating?
No. Bloating is the subjective sensation of abdominal fullness, pressure, or swelling, whereas abdominal distension is a visible increase in abdominal size. Abdominophrenic dyssynergia is one mechanism that can contribute to visible distension, particularly in people with disorders of gut–brain interaction.
3. What causes abdominophrenic dyssynergia?
The exact cause is not completely understood. It appears to involve abnormal gut–brain signalling and altered reflex control of the diaphragm and abdominal muscles. It can occur in conditions such as irritable bowel syndrome (IBS), functional abdominal bloating and distension, constipation, and other disorders of gut–brain interaction.
4. Why does the abdomen become visibly distended?
When intestinal contents, gas, or other stimuli increase abdominal pressure, the normal abdominal accommodation response may become abnormal. The diaphragm can descend rather than relax upward, while the abdominal wall becomes less contracted. This combination pushes the abdominal contents forward, producing a visibly distended abdomen.
5. Does abdominal distension always mean there is excessive gas?
No. Visible distension does not necessarily mean that a large amount of gas has accumulated. Some people with severe distension have relatively normal amounts of intestinal gas. Abnormal muscle coordination and altered perception of intestinal sensations can contribute significantly to the appearance and sensation of distension.
6. Is abdominophrenic dyssynergia related to the gut–brain axis?
Yes. It is considered an example of altered gut–brain interaction. Signals from the gastrointestinal tract are processed by the nervous system and can influence the coordinated activity of the diaphragm and abdominal wall. Stress and heightened visceral sensitivity may therefore worsen symptoms in some individuals.
7. How is abdominophrenic dyssynergia diagnosed?
There is no single routine test that confirms the condition. Diagnosis is generally based on the characteristic pattern of bloating and visible abdominal distension after excluding other important causes. Specialist investigations can sometimes assess abdominal wall and diaphragm movement, but these are not routinely required.
8. How is abdominophrenic dyssynergia treated?
Treatment focuses on the underlying disorder and reducing the abnormal abdominal muscle response. Dietary management, treatment of constipation or other gastrointestinal disorders, and brain–gut behavioural therapies may be helpful. Diaphragmatic breathing and targeted physiotherapy techniques may also help some patients improve coordination between the diaphragm and abdominal wall.
9. Can abdominophrenic dyssynergia be mistaken for SIBO?
Yes. Significant abdominal distension can occur in both conditions, and the symptoms can overlap. However, visible distension does not by itself indicate SIBO. If SIBO is suspected, the diagnosis should be based on the overall clinical picture and appropriate testing rather than abdominal distension alone.
10. When should I see a doctor about persistent abdominal distension?
Persistent or recurrent abdominal distension should be assessed if it is severe, new, progressively worsening, or associated with unexplained weight loss, gastrointestinal bleeding, persistent vomiting, fever, anaemia, severe abdominal pain, or a significant change in bowel habits. These features may indicate another gastrointestinal condition that requires investigation.