A condition associated with diabetes, in which the emptying of the stomach is slowed. Normally, the digestion of food is facilitated by steady, rhythmic contractions of the stomach muscles that break down food into smaller particles. These muscle contractions are also what push food into the small intestine, where it is further digested and its nutrients absorbed.
After having diabetes for many years, some people develop a condition known as diabetic autonomic neuropathy, in which the nerves that control automatic functions in the body, such as heartbeat and digestion, are damaged. If the vagus nerve, which controls the movement of food through the digestive tract, is damaged, the stomach and intestinal muscles may not function properly, and the passage of food through the digestive tract may be slowed.
The most common symptoms of gastroparesis are heartburn, nausea, vomiting, bloating, and an early feeling of fullness when eating. Some other signs and symptoms include weight loss, erratic blood glucose levels, lack of appetite, gastroesophageal reflux (stomach contents backing up into the esophagus), and spasms of the stomach wall.
When a doctor suspects gastroparesis based on a person’s symptoms, he may use one or more of the following tests to confirm it:
- In a barium x-ray test, a person fasts for 12 hours and then drinks a thick liquid containing barium, an element that appears bright white in x-rays. Normally, the stomach would be empty after a 12-hour fast, so if the x-ray reveals food in the stomach, the person is probably affected by gastroparesis. If no food shows up in the stomach but the doctor still suspects gastroparesis, the test may need to be repeated on another day since the rate of digestion may vary from day to day.
- In a barium beefsteak meal, a person eats food that contains barium, allowing the radiologist to observe the stomach in the process of digestion. If it takes a long time for the stomach to digest the meal and for the food to leave the stomach, gastroparesis is a likely cause.
- In the radioisotope gastric-emptying scan, a person eats food containing a harmless amount of a radioactive substance. Using a machine that can detect the substance, doctors create an image of the food to see how quickly it leaves the stomach.
- In gastric manometry, a wire that measures the stomach’s electrical and muscular activity is placed in a thin tube and inserted down the throat into the stomach. Doctors monitor the results during digestion to see how well the stomach is working.
Other tests may be performed to rule out other conditions or causes of gastroparesis other than diabetes.
- Certain breath tests can rule out conditions such as peptic ulcer. Studies are also being done to assess the accuracy of the hydrogen breath test in diagnosing gastroparesis. The concentration of hydrogen in the breath several hours after a meal can be an indicator of digestion speed.
- An upper endoscopy allows a doctor to see the lining of the stomach and to look for any abnormalities that may be causing slowed stomach emptying. After the person receives a sedative, the doctor passes a long, thin tube called an endoscope through the mouth into the stomach.
- If a doctor suspects that gallbladder disease or pancreatitis might be the cause of gastroparesis, he may use an ultrasound test to investigate those possibilities. The ultrasound test uses sound waves to outline the shape of the gallbladder and pancreas.
Although the exact cause of neuropathy (and hence gastroparesis) isn’t known, it is clearly associated with high blood glucose levels. In addition, high blood glucose can directly cause delayed gastric emptying. Good blood glucose control, therefore, is the mainstay of treatment for gastroparesis. However, because gastric emptying can be so unpredictable, maintaining blood glucose control can be difficult. It may involve frequent blood glucose monitoring and additional insulin injections.
In the United States, there are a few drugs either available or in development to treat gastroparesis. The antibiotic erythromycin increases the muscle contractions that push food through the stomach and is sometimes prescribed to treat gastroparesis. Metoclopramide (brand name Reglan) is a “prokinetic” drug, which means it stimulates stomach muscle contractions; it also reduces nausea and vomiting. Unfortunately, it can have troubling side effects such as depression, anxiety, and movement disorders. Domperidone, a prokinetic drug like metoclopramide, helps with stomach muscle contraction and eases nausea. It has been used elsewhere in the world and is currently under review by the U.S. Food and Drug Administration.
Dietary changes may also help alleviate symptoms of gastroparesis. In some cases, people are instructed to eat five or six small meals a day rather than fewer large ones to prevent the stomach from becoming too full. Sometimes a doctor or dietitian prescribes special liquid meals until the gastroparesis resolves, because liquid meals pass through the stomach more easily. Doctors often recommend avoiding foods high in fat or high in fiber because fat and fiber are difficult to digest.
For cases of gastroparesis that don’t respond adequately to lifestyle changes and medication, some more invasive procedures might help:
- A feeding tube, called a jejunostomy tube, may be inserted through an incision in the abdomen and into the small intestine. The feeding tube allows nutrients to reach the small intestine without going through the stomach. The feeding tube is temporary for most people and is removed once the gastroparesis becomes less severe.
- Parenteral nutrition involves delivering nutrients directly into the bloodstream through a catheter inserted in a chest vein. It is usually a temporary measure used during very severe bouts of gastroparesis.
- A new device called a gastric neurostimulator is sometimes used to improve the symptoms of gastroparesis in people who don’t respond adequately to medication. It is surgically implanted and emits electrical pulses that help control nausea and vomiting.
- Recent studies also show that botulinum toxin (Botox) injections to the pylorus muscle, which regulates food passage from the stomach, can temporarily paralyze the muscle, allowing food to move from the stomach into the small intestine more easily.
Diabetic gastroparesis can be a very difficult condition to treat. However, by making lifestyle changes and taking steps to get medical help, many people eventually find relief from its symptoms.