There isn't enough evidence yet to say whether widespread screening for celiac disease makes sense, according to draft guidelines proposed by U.S. physicians.
The draft recommendations issued by the U.S. Preventive Services Task Force (USPSTF) today conclude that more research is needed on the potential health benefits of screening people without symptoms, particularly for individuals at increased risk for celiac disease due to diabetes or a family history of celiac disease.
"In the face of unclear evidence, doctors should use their clinical judgment when deciding whom to screen," said task force member Dr. Alex Krist, a researcher in family medicine and population health at Virginia Commonwealth University in Richmond.
"The Task Force encourages people with an increased risk of celiac disease to talk to their doctor about what tests are best for them," Krist added by email.
About one in 133 Americans have the disease, according to the University of Chicago Celiac Disease Center. That fraction rises to one in 22 among first-degree relatives of people with celiac disease, the center says.
Celiac disease can be detected with a blood test for antibodies that show an immune response to gluten in the gastrointestinal tract, and may also be confirmed by a biopsy of the small intestine.
People with celiac disease are advised to go on a gluten-free diet to ease symptoms such as abdominal pain, bloating, gas, diarrhea, anemia and weight loss. The draft guidelines don't apply to people who have these symptoms.
The USPSTF, a government-backed independent organization that reviews medical evidence, issues recommendations that are closely watched by doctors and insurers. This is the first time the USPSTF has weighed in on screening for celiac disease, and the task force will accept public comments until May 30 before releasing final guidelines.
One concern with widespread screening is that biopsies aren't risk-free and may confirm cases of celiac disease that weren't causing problems for patients and didn't necessarily require treatment, Krist noted.
While the blood test is simple, widely available and inexpensive, an expensive and invasive intestinal biopsy is typically needed to confirm the diagnosis, said Dr. Joseph Murray, director of the celiac disease program at the Mayo Clinic in Rochester, Minnesota and an author of screening guidelines issued by the American College of Gastroenterology.
Guidelines for gastroenterologists recommend celiac screening for people with a close relative with celiac and for diabetics who are at increased risk for the disease, Murray said by email.
The most controversial aspect of the USPSTF draft recommendations is the lack of recommendation for this subset of people with an increased risk, Murray added.
"In my experience as a clinician, as well as some studies that have been undertaken, many of the individuals who are family members have symptoms, though they may not have complained of those symptoms to their doctors, sometimes because they did not realize they were an abnormality and sometimes because they were never asked," said Murray, who wasn't involved in drafting the USPSTF recommendations.
"In that circumstance, I often find in my practice that patients who go on a gluten-free diet, who themselves did not even appreciate the symptoms, often feel better," Murray added.
A lack of data shouldn't stop screening of people with an increased risk, said Alice Bast, chief executive officer of Beyond Celiac, a patient advocacy organization that contributed comments to the USPSTF to help shape the screening recommendations.
"There is a lack of evidence from randomized trials with clinical outcomes to guide the USPSTF," Bast said by email.
"But lack of data doesn't mean that there is no need for screening at-risk populations," Bast added. "The risk posed by the potential long-term health complications far outweighs the inconvenience and potential downsides."
The complications of untreated celiac disease, according to the Mayo Clinic's web site, can include malnutrition, low bone density, lactose intolerance and infertility.