A gluten-free diet (GFD) can benefit asymptomatic patients who test positive for celiac disease based on detection of with endomysial antibodies (EMA), researchers report in the September issue of Gastroenterology. This finding supports screening of patients at risk for celiac disease.
Celiac disease is a lifelong disorder caused by ingested gluten in predisposed individuals. The prevalence in the European and North American population is estimated to be 1%–2%. Celiac disease is diagnosed based on detection of antibodies against transglutaminase 2 and (EmA) in serum samples and demonstration of small-bowel mucosal damage.
Since the disorder is common but difficult to detect, some people have proposed screening the entire population, using serologic tests. However, the tests can detect individuals who are asymptomatic, with only mild enteropathy or even normal small-bowel mucosa. Because the only treatment for celiac disease is a lifelong strict GFD, which is restrictive and difficult to maintain, it is not clear if screening would benefit these individuals.
Kalle Kurppa et al. investigated whether asymptomatic adults who test positive for EmA benefit from screening and subsequent GFDs.
Celiac disease runs in families, so Kurppa et al. tested more than 3000 family members of patients with celiac disease for EMA. Of the 140 (4.6%) who tested positive, 40 were randomly assigned to GFDs or normal diets for 1 year.
The 40 subjects denied having prominent symptoms of celiac disease when the study began. However, most had evidence of enteropathy of the small intestine, based on biopsy analysis. Interestingly, the EMA-positive individuals also had higher Gastrointestinal Symptom Rating Scale scores at diagnosis, indicating that people with some symptoms and clear risk factors for celiac disease go undiagnosed.
These individuals improved with the GFD. Kurppa et al. found that after 1 year on the GFD, subjects’ ratios of villous height:crypt depth increased, levels of celiac-associated antibodies decreased, and gastrointestinal symptoms improved to a greater extent than in patients on gluten-containing diets. The GFD group also had reduced indigestion, reflux, anxiety, and better health, based on the visual analog scale, than the gluten-containing diet group. Kurppa et al. say that these results support screening of patients at risk for celiac disease.
In an editorial that accompanies the article, Daniel A. Leffler and Ciarán P. Kelly conclude that screening detects patients with undetected celiac disease whose symptoms improve on the GFD.
They state that the findings of Kurppa et al. provide some of the strongest data to support screening of family members of patients with celiac disease. However, the editorial also points out that the study was confined to Finland, which is the most accommodating for individuals on GFDs. Most restaurants provide well-labeled, gluten-free options, the government provides stipends to help cover the costs of GFDs, and clinicians are well trained in celiac disease management. It is not clear if GFDs would be as easy to maintain in other countries.
Furthermore, even in Finland, individuals who learned they had celiac disease through screening reported a modest but significant deterioration of social function. SF-36 social functioning scores decreased in the GFD group.
Leffler and Kelly state that it is therefore not clear whether offering a diagnosis that could improve gastrointestinal symptoms, but simultaneously worsens socialization and offers limited overall change in health-related quality of life, is helpful to patients.
They conclude that these uncertainties, along with the expense to the health care system of a screening program, currently make the cost of identifying individuals with asymptomatic celiac disease too high, unless and until additional more substantial benefits can be demonstrated.
Kurppa et al. state that their results support active screening of celiac disease in at-risk groups, but prospective studies are needed to determine whether seropositive subjects with normal small-bowel mucosal histology should be placed on GFDs.