Am J Gastroenterol. 2003 Feb;98(2):377-81 Celiac.com 07/31/2003 - The findings of this new study are very significant for families of those with celiac disease. The results indicate that 17% of those related to two celiac disease-diagnosed siblings will also have the disease. Past studies have shown that around 10% of first-degree relatives of celiacs also have it, but this study is unique as it focuses on the increased risk for families where two siblings have the disease. This study further emphasizes the conclusions of past studies: If you have a relative with celiac disease--get tested, especially if it is a first-degree relative. - Scott Adams
"Prevalence of celiac disease among relatives of sib pairs with celiac disease in U.S. families
Am J Gastroenterol. 2003 Feb;98(2):377-81
Book L, Zone JJ, Neuhausen SL.
Division of Pediatric Gastroenterology and Nutrition, Department of PediatricsUniversity of Utah, Salt Lake City, USA.
OBJECTIVE: Celiac disease is a familial malabsorptive disorder with an estimated prevalence in first-degree relatives of 10-12%. The prevalence for first-degree and more distant relatives has not been determined in families where there are two affected first-degree relatives. The aim of our investigation was to estimate the prevalence and relative risk for celiac disease in relatives of two siblings diagnosed with celiac disease.
METHODS: We ascertained sib pairs with celiac disease, and then identified all living first-degree relatives and available second-degree relatives to minimize ascertainment bias. We measured IgA endomysial antibodies, a highly specific and sensitive assay for celiac disease, in all subjects without a confirmed biopsy diagnosis. For those individuals with positive serologic tests, IgA tissue transglutaminase antibody tests and human leukocyte antigen DQA1 and DQB1 genotyping were performed for additional confirmation. Individuals with positive biopsy and/or serology were considered affected. We calculated the relative risk of being affected with celiac disease using the lambda® statistic.
RESULTS: The prevalence of celiac disease in relatives of affected sib pairs was as follows: 21.3% (13/61) of siblings (lambda(S) = 53); 14.7% (10/68) of offspring (lambda(O) = 37); 17.2% (28/163) of first-degree relatives; 19.5% (16/82) of second-degree relatives; and 17.8% (52/292) of all relatives (lambda® = 44.5).
CONCLUSIONS: In these families, we identified a sibling risk approximately double that found in previous reports, as well as significant risk for more distant relatives, probably because of sharing of a common gene. In families where at least two siblings have been diagnosed with celiac disease, relatives are at high risk for celiac disease. Screening should be considered for all family members.