Screening first-degree relatives of Celiac Disease patients, does it affect gastro-intestinal symptoms and quality of life?

Celiac Disease (CD) is an affliction which occurs in genetically susceptible
individuals upon the ingestion of gluten. The prevalence of CD in the general
population is estimated to be 0.5-1%, but approaches 16% in first degree
relatives. Given this increased prevalence rate every time an index patient is
diagnosed, first degree relatives will often be screened for CD.
In symptomatic individuals, approximately half of the first degree relatives, a
gluten free diet significantly improves gastrointestinal symptoms and the
quality of life. Therefore, screening is justified in symptomatic relatives. By
contrast, in asymptomatic individuals it is unknown whether they will benefit
from a gluten free diet, either physically or psychosocially. Despite this,
symptom free relatives of an index patient with CD are often being screened for
CD

The aim of this randomized controlled trial is to determine the affect of
screening on the Gastrointestinal symptoms (GIS) and Health Related Quality of
Life (HRQL) in asymptomatic first degree relatives of CD patients. On the basis
of the results, it would be possible to conclude whether screening is justified
in this group.

Subjects will be included over a period of 2 years. Directly after informed
consent, all subjects will receive two sets of questionnaires, validated to
measure HRQL, using the SF-36, and GIS, using the Gastro-intestinal Symptoms
Questionnaire. Subsequently, all symptomatic relatives will be screened for CD.
Asymptomatic relatives will be randomized to either immediate screening, or the
option to have these investigations done later on. Six months after screening
or randomization, the questionnaires will be distributed again.
Along with the questionnaires, the participants will be asked to report the
total days of absence from work or school.

Screening is done in a two step approach: firstly by determining HLA-DQ2/DQ8,
and if any of these HLA class I molecules are present, the determination of
IgA-antiendomysium antibodies (EMA), and IgA-tissuetransglutaminase antibodies
(TTG), as well as total IgA. Those relatives with abnormal results for either
EMA or TTG will be offered a small intestinal biopsy to prove the existence of
CD. This is the standard diagnostic approach in symptomatic and asymptomatic
persons. Subjects in whom celiac disease is confirmed, will start a gluten free
diet.

Because the diagnostic approach to screen for CD will not be different from the
approach maintained in clinical practice, no increased risk to the participants
is expected. The burden associated with participation in this study is thought
to be minimal as filling out the questionnaires is expected to take only 30
minutes