Final step in diagnosing celiac disease often doesn’t occur even when blood tests indicate the need

Children least likely to get endoscopy and biopsy that confirms celiac disease, Beyond Celiac research shows

By Amy Ratner, director of scientific affairs

Overall, about 30 percent of people who have had a positive blood test for celiac disease don’t go on to get a confirming endoscopy and biopsy, but in children that number jumps to about 50 percent, according to new research by Beyond Celiac.

In addition to age, gender and race led to disparities in determining who gets appropriate follow-up care after having a positive blood test result, according to an analysis of a US-based insurance claims database. The results were presented this week by Beyond Celiac as a poster at Digestive Disease Week (DDW), the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery.

The reason children get an endoscopy and biopsy less frequently than adults is not certain, but it may be due to parents’ worry about children having the invasive procedure, the study says. Children from one to 10 were the least likely to have the follow-up procedure.

During an endoscopy, a very thin, flexible tube is snaked from the mouth to the small intestine, and a small tool is used to take tissue samples, called biopsies, from the wall of the intestine. Patients are sedated, with the type and amount of sedation dependent on age and any other co-existing medical conditions.

When endoscopies should be done

Guidelines from US organizations for gastroenterologists recommend that a positive blood test should lead to an endoscopy and biopsy, currently the gold standard for diagnosis of celiac disease in the United States for adults and children.

However, European guidelines for very young children do not always require an endoscopy and biopsy, allowing a celiac disease diagnosis to be made based on very high levels of celiac disease antibodies in several blood tests. Physicians who treat young children in the United States may use these guidelines as a reason not to do an endoscopy and biopsy, the study says.

“Similarly in adults, physicians may be comfortable diagnosing celiac disease based on a positive [celiac disease] screening test and don’t proceed with the endoscopy in some patients,” the authors wrote.

Private health insurance claims used

Beyond Celiac used a database of private health insurance and Medicare Advantage claims to determine whether the guidelines were being followed and if there were any differences by demographics. The study was based on about 19 million patients, a 25 percent representative sample of the database. Those with claims that indicated they had not been previously diagnosed with celiac disease were included in the analysis.

Nearly 9000 patients had a positive celiac disease blood test but only about 70 percent of those had the recommended endoscopy and biopsy. More women than men had the proper follow up, 72 percent compared to 67 percent.

Significantly more non-Hispanic Whites, at about 73 percent, and significantly fewer non-Hispanic Asians, at about 59 percent, had the endoscopy and biopsy. It’s not clear why non-Hispanic Asians are not followed up appropriately, the study notes. Those who had unknown or missing race data also were significantly less likely to be followed up correctly. About 71 percent of Non-Hispanic Black people received proper diagnostic follow up.

Among those with positive diagnostic celiac disease blood tests, non-Hispanic whites made up the largest group, at 71 percent, followed by Hispanics at about 10 percent, non-Hispanic Black people at about 7 percent and non-Hispanic Asians at about 3 percent. More than 8 percent of those with positive blood tests had missing or unknown race data. More women than men also had a positive blood test result.

While celiac disease affects about one percent of the population worldwide, 50 to 80 percent of patients are estimated to be undiagnosed. Lack of thorough follow-up with an endoscopy and biopsy could be a contributing factor to low diagnosis rates because these procedures are needed to confirm celiac disease in those with positive blood test results. Patients who go on a gluten-free diet without a definitive diagnosis have to eat gluten again for about six weeks before endoscopy and biopsy results are accurate.

Why follow-up is not done

While the study highlights some demographic disparities in who gets proper diagnostic follow-up, the reasons are not clear, the authors wrote.

“This dataset does not allow for conclusions to be drawn about whether it was the patients, their healthcare provider or another cause the led to the missed follow-up endoscopy and biopsy after a positive celiac disease screening test,” the authors wrote.

The study calls for more research to understand disparities. It was funded by Takeda Pharmaceuticals.

Similar results were presented recently at ISPOR, a meeting of the Professional Society for Health Economics and Outcomes Research.

Studies presented at DDW are sometimes preliminary and give an early look at investigations that are likely to include more details as they progress toward publication in a peer reviewed scientific journal. Studies selected to be presented at DDW go through a review process.