Diabetes and Your Stomach: Not Always a Good Match

By John W. Jacobs , Jr. , MD

Mark Twain, the famous American author, once wrote, “Part of the secret of a success in life is to eat what you like and let the food fight it out inside.” For thousands of patients in the United States who suffer from gastroparesis (GASS-troh-puh-REEsiss), every day may feel like they are waging a constant battle in their stomachs. Gastroparesis literally means stomach paralysis, and while there is an increased awareness about the condition, many patients still suffer silently with symptoms of nausea, vomiting, bloating, heartburn and abdominal pain. Gastroparesis is also called delayed gastric emptying Normally, following a meal the wall of the stomach contracts. The vagus (VAY-ges) nerve -- one of two extremely long nerves that extend from the brain stem to the abdomen -- stimulates this process, which in turn helps to break up eaten food and mix it with powerful digestive enzymes. These contractions also propel the food forward, out of the stomach and into the small intestine. When this highly coordinated process is working properly, the stomach empties normally and our sense of fullness after a meal goes away. However, with gastroparesis the contractions do not occur, or do not occur in an orderly fashion. When this happens, the stomach empties food into the small intestine much more slowly. In some individuals, the stomach may not even empty completely between meals. When the next meal is eaten, the meal then adds to what is already in the stomach and fullness, nausea and even throwing up can occur. Slowing of stomach emptying can be a normal process seen with aging. Also, a meal that is high in fat can slow stomach emptying. When you have the flu, this too can slow how fast your stomach empties. Many medications can affect stomach emptying. But the most common known cause of gastroparesis, accounting for approximately 20 percent to 30 percent of cases, is diabetes, typically when diabetes has been poorly controlled over a long period of time. Although gastroparesis is a more common complication of type 1 diabetes (the diabetes that is an autoimmune process where antibodies are formed that attack the insulinproducing cells in the pancreas), it can also occur in patients with type 2 diabetes (the diabetes in which insulin does not act as well as it should, and in which there is a decrease in insulin production over time). Possible causes include connective tissue disorders, disorders involving the lining of the stomach itself, viral infections, neurologic or autoimmune conditions, and a history of surgery on the stomach. Despite the many possible causes of gastroparesis in diabetes, most with the condition have what medical experts believe is “idiopathic” gastroparesis, meaning the mechanism causing the problem is unknown. The symptoms of gastroparesis are quite variable from person to person. Some people have symptoms of nausea and vomiting. If these symptoms continue over a long period of time, this can lead to dehydration, weight loss and the need for hospitalization. Other individuals may present with bloating, abdominal pain, heartburn and a feeling of fullness soon after eating. And to make the picture even more confusing, for any one person, symptoms may vary from day to day and from week to week! Thus, it’s not surprising that so often the diagnosis of gastroparesis is delayed as the symptoms could be interpreted as stomach acid reflux or having eaten something that was not agreeing with a person's body. There are several steps involved when evaluating for possible gastroparesis. A full health history, physical examination, and blood tests such as blood counts, levels of chemistries such as sodium and potassium, blood sugar control, thyroid function and nutritional status are recommended. It is also important for the physician to rule out any obstructions or other structural problems which could be causing symptoms. A common test performed is an upper endoscopy, which involves placing a thin, flexible tube into the esophagus (your swallowing tube), stomach and first part of the small intestine. This allows a look at the inside of these organs and to take tissue samples if necessary. Depending on the specific symptoms and early evaluation, a physician may also recommend further imaging with either a CAT scan of the abdomen and pelvis or an upper gastrointestinal series. This latter test involves drinking a fluid called barium, which coats the inside of the organs in the upper gastrointestinal tract. A series of x-rays are then taken, which allows a physician to further evaluate function as well as the appearance of these organs. A frequently recommended test to help diagnose gastroparesis is a gastric emptying scan. Before the test, it is important to stop medications which are known to slow down the stomach, as these medications could impact the results of the test. At the start of this test the person is given a meal mixed with a very small amount of radioactive material. This material is in such low doses that it is not harmful. A machine then scans for how much of the meal is left in the stomach at one, two, three and four hours after the meal. The mixture of meal and radioactive tracer is visualized on the scan and allows a physician to calculate how quickly the food leaves the stomach. If the mixture leaves too slowly, this would support delayed gastric emptying and the diagnosis of gastroparesis. While gastroparesis is a chronic condition and there is no known cure for it, there are several treatment approaches that can significantly help control the condition. Treatment is individualized and based on overall health, type and severity of symptoms, and preferences. Often treated through dietary changes as an initial step, meals should be small and more frequent. Eating five to six smaller meals per day instead of three large can result in less bloating and nausea. Avoiding foods that are high in fat and fiber can be very helpful, as fat slows down digestion and foods that are high in fiber can be more difficult to digest. Some individuals may also benefit from a liquid or puréed diet. Treatment often also includes the use of medications not only to control symptoms of gastroparesis such as nausea and heartburn, but also to help the stomach empty more effectively. When dietary changes and medications are not effective, nutrition can be given a different way. Placing a feeding tube through the skin and into the small intestine, or placing a special catheter in a chest vein to deliver an intravenous food, results in bypassing the stomach, thereby avoiding the symptoms of delayed stomach emptying. An alternative and increasingly researched and utilized treatment is the placement of a gastric electrical stimulator. This is a small device that is surgically placed into the abdomen and sends tiny electrical pulses into the stomach. It is not well understood how this helps, but studies looking at symptom improvement suggest that nausea and vomiting might be significantly decreased over time. Managing gastroparesis for those with diabetes can be very challenging. It is extremely important to maintain good blood glucose control. However, since food is absorbed more slowly, stomach emptying can be unpredictable. As a result, a person’s blood glucose levels can fluctuate and be difficult to control. Since it will typically be necessary to adjust the dosing and timing of insulin, it is crucial to closely monitor blood glucose levels and to follow up with your endocrinologist. If you would like to learn more about gastroparesis, speak with your endocrinologist or visit the National Institute of Health’s National Digestive Disease Clearinghouse at http://digestive.niddk.nih.gov/ddiseases/pubs/gastroparesis/ or the Gastroparesis Patient Association’s website at www.g-pact.org.

Dr. John W. Jacobs, Jr. is a third-year Gastroenterology Fellow at Indiana University. He graduated from the University of Miami, Miller School of Medicine, and completed his internal medicine residency training at the University of Texas, Southwestern Medical Center in Dallas. He is board certified in internal medicine. Dr. Jacobs is interested in all aspects of general gastroenterology and has a particular research focus on diseases of the esophagus and stomach.