Originally thought to affect only the young, celiac disease may actually develop in older people too, according to a new study out of Finland. The study was published in the June 29, 2009 issue of BMC Gastroenterology.

Celiac is an autoimmune disease that essentially causes the body to attack the small intestine when a person eats foods containing a type of protein called gluten. (Many products advertize that they are gluten−free for this reason; gluten is found in wheat, barley, and rye.) Over time, the small intestine can become so injured from these attacks that it is unable to absorb nutrients effectively, which can lead to vitamin deficiencies. Celiac disease affects about 1% of people in the Western world.

Anitta Vilppula and her colleagues at Päijät−Häme Central Hospital in Lahti, Finland had found early evidence of celiac disease in older people and wanted to determine whether it had been there undiagnosed all along or if it had developed later in life.

The team followed 2,815 randomly selected men and women over the age of 55, who had all undergone initial celiac screening (this is typically done by blood test, but the researchers also took biopsies of the participants’ small intestines to confirm the blood test results). Three years after the original test, 2,216 of the participants were retested.

The researchers found that there were five new cases of celiac disease confirmed at the second testing, and three of these individuals were symptom−free. The other two had only mild symptoms. The researchers say that their results suggest that celiac disease can actually develop in middle−age or later.

The authors urge doctors to be aware of this phenomenon, and to keep in mind that a negative celiac test in the past does not necessarily mean that a patient could not develop the disease at a later point in time.