July 1 (HealthDay News) -- Celiac disease, a serious digestive system disorder, has become far more common in recent years, a new Mayo Clinic study has found.

According to a report in the July issue of Gastroenterology, the disease is four times more prevalent in the United States today than in the 1950s. In addition, the researchers found that the death rate was four times higher during the 45 years of the study among people who had the disease but did not know it than it was among those who did not have celiac disease.

"Celiac disease has become much more common in the last 50 years, and we don't know why," said Dr. Joseph Murray, a Mayo Clinic gastroenterologist who led the study. "It now affects about 1 in 100 people."

Celiac disease is caused by an intolerance to gluten in wheat, barley and rye. An autoimmune reaction damages the small intestine and can cause severe diarrhea, abdominal discomfort, weight loss, anemia, unexplained infertility, loss of teeth and even premature or severe osteoporosis. Treatment is mainly a lifelong adherence to a diet free of gluten, a protein.

The Mayo researchers tested blood samples gathered at Warren Air Force Base in Wyoming between 1948 and 1954. They compared the results with those from two recently collected sets of blood samples from people in Olmsted County, Minn.

Murray said the findings were important because they show the need to educate more people, patients and health-care providers alike, about the disease, which he said might be emerging as a public health issue.

Celiac disease is sometimes misdiagnosed or undiagnosed because symptoms are similar to diseases such as irritable bowel syndrome.

"Something has changed in our environment to make [celiac disease] much more common," Murray said. "This study suggests that we may need to consider looking for celiac disease in the general population, more like we do in testing for cholesterol or blood pressure."

SOURCE: Mayo Clinic, news release, July 1, 2009