Functional Dyspepsia: Digestive Disorders

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Functional dyspepsia

You're having trouble with your stomach. You feel uncomfortable. It's not heartburn, but it may be related to eating. You feel bloated and full. You complain of nausea, or sometimes you even vomit. You think you might be having "indigestion."

Doctors call it dyspepsia — literally, "bad digestion." The word is derived from the Greek dys, which means bad, and peptein, which means "to cook" or "to digest."

The term functional dyspepsia (FD) is used to describe persistent upper abdominal pain that's often related to eating, and for which there is no identifiable cause such as peptic ulcer disease. Because peptic ulcer disease produces similar symptoms, functional dyspepsia is sometimes called nonulcer dyspepsia.

In most cases, the uncomfortable upper abdominal symptoms appear after eating, but there's no difficulty in swallowing. Sometimes the discomfort begins during the meal, sometimes about half an hour later. It tends to come and go in spurts over a period of about three months.

This condition affects about a quarter of the population — twice as many as have peptic ulcer disease — and it hits men and women equally. It's responsible for a significant percentage of visits to primary care doctors. Many people suspect they're suffering from ulcers, but are found not to be. The cause of FD is unknown. Even more frustrating, there's no surefire cure.

The first question on most people's minds is, "Do I have an ulcer?" It's not an unreasonable question, considering that 10% of Americans develop a peptic ulcer at some time in their lives. And it's important to answer it quickly. Ulcers can have serious complications, while FD generally does not. Ulcers can be treated with medications, while in most cases medications don't do much to remedy FD.

Peptic ulcers are raw, crater-like breaks in the mucosal lining of the digestive tract. They occur in the stomach and duodenum and are linked to the erosive action of gastric acid and sometimes to a reduction in protective mucus. In essence, the stomach, which is designed to digest foods, is digesting a part of its own lining. These localized, generally circular craters are rarely more than an inch in diameter.

In the early 1980s, researchers made a major discovery. They identified Helicobacter pylori, a spiral bacterium with an affinity for the stomach, as a major culprit in ulcer disease. H. pylori is the cause of many peptic ulcers (see Figure 7). At least 90% of people with duodenal ulcers and 75%–85% of those with gastric (stomach) ulcers are infected with this organism.

Figure 7: How an ulcer starts The corkscrew-shaped bacterium Helicobacter pylori attaches to the surface of the stomach by twisting through the mucus that protects the stomach lining from corrosive gastric juices.

The percentage of ulcers that are not caused by H. pylori has increased; researchers are not yet sure why. Other causes of ulcers include irritating substances such as aspirin, ibuprofen, and other NSAIDs. Cigarette smoking impairs the healing of ulcers, and stress appears to aggravate ulcer symptoms. Studies show there's also a genetic component, as peptic ulcers sometimes run in families. They occur more often in people with type O blood than in those with other blood types. Sometimes there is no known cause.

Last updated:	August 21, 2007