Celiac Disease - NIH Consensus Development Program - National ...

Consequences of Testing for Celiac Disease Ann Cranney, M.D., M.Sc.ContextThe prevalence of silent cases of celiac disease (CD) may be eight times that ofclassically symptomatic CD, and it is important to determine if the consequences of testing andthe response to treatment differs by mode of diagnosis, and clinical presentation.ObjectiveTo conduct a systematic review of the expected consequences of testing for CD in thefollowing populations: (a) patients with symptoms suggestive of CD, (b) asymptomatic at-riskpopulations, and (c) the general population.Data SourcesA comprehensive literature search was conducted by the National Library of Medicinein collaboration with the University of Ottawa Evidence-Based Practice Center (UO-EPC). Thesearches were run in MEDLINE (1966–Oct 2003), EMBASE (1974–Dec 2003), CAB(1972–Dec 2003), PsycINFO (1840–2003), AGRICOLA (1970–2003), and SociologicalAbstracts (1963–2003).Study Selection and Data ExtractionThis review was conducted using accepted systematic review methodology. Twoindependent reviewers selected the articles using three levels of screening. The strategy includedarticles that dealt with the consequences of testing for CD. We did not include articles that dealtwith consequences addressed in celiac objectives one and two (e.g., cases diagnosed,false-positive results, invasive procedures [biopsies], and followup testing). Full data extractionwas conducted on all articles that met the level 3 screening requirements by one reviewer andthen verified by a second reviewer. The quality of the included studies was assessed. Outcomesincluded: (1) nutritional parameters (body composition and anthropometrics), anemia, anddiabetic control; (2) compliance with a gluten-free diet (GFD); (3) costs; and (4) other clinicalendpoints ( [a] osteoporosis and [b] mortality).Data SynthesisThe studies identified dealt primarily with small populations of symptomatic individualsand not all studies reported clinical presentation in detail. The number of studies evaluatingoutcomes in asymptomatic, screen-detected patients was small, and it was difficult to determineif outcomes differed by population and clinical presentation. The majority of studies evaluating87