A Population-based Study of Celiac Disease in South Europe in Children Between 1 to 5 Years of Age
Condition: Celiac Disease
MeSH terms: Celiac Disease
Study type: Observational

Summary: 
      Celiac disease (CD) was diagnosed for years almost exclusively in children. This is due to
      the fact that in adulthood it manifests in a much more attenuated form, while the classic
      form with severe diarrhea, malnutrition and dehydration is observed almost exclusively in
      children. Classic studies, carried out prior to the widespread use of serology as a CD
      diagnostic tool, already showed that there is variability in gluten sensitivity and that in a
      non-negligible proportion of cases (10%) gluten sensitivity appears to be transient.
      Subsequent studies, including patients diagnosed by serology or population screening studies,
      suggest that progression to gluten latency or tolerance may occur in a higher proportion of
      patients, ranging from 20 to 50% depending on the geographical region.

      In the first decade of the 2000s, the researchers group performed a prevalence observational
      cross-sectional study survey in Catalonia (autonomous region in the northeast of Spain) that
      accurately reflected the distribution of the reference Catalan population in terms of sex and
      age. The results showed a drastic and significant drop in the prevalence of CD disease in
      relation to age, with the prevalence of CD in children being 5 times higher than adults (1:71
      vs. 1:357). Strikingly, the reduction in prevalence was especially notable in the first 4
      years of life.

      Two possibilities were proposed to explain this unexpected finding in a disease that is
      lifelong: 1) The existence of an environmental effect (cohort effect) acting as a disease
      trigger in early childhood during the study period (e.g., bacterial or viral infections,
      vaccines, food policies related to gluten introduction, use of antibiotics, etc.). 2) The
      appearance of age-related tolerance to gluten in a proportion of cases. Interestingly, it has
      been suggested that immunological tolerance might be more frequent in children diagnosed with
      CD before the age of two.

      The aims of the present epidemiological study are: 1) to determine the prevalence of CD in
      Catalonia in children under 5 years of age and compare it with the results obtained in the
      previous 2004-2007 study; 2) to investigate the potential effect of environmental factors on
      disease prevalence; and 3) to evaluate longitudinally the appearance of tolerance to gluten
      in the CD cases detected. Therefore, this study has been designed using exactly the same CD
      screening methodology and reproducing the reference population in the same geographical area
      as the previous 2004-2007 study.
    


Observational model: Cohort
Time perspective: Other
Sampling method: Probability Sample
Study population: 
        Pediatric patients from ambulatory minor surgery departments (= general population sample).
        Regarding age and sex, inclusion is done reproducing the reference population of the area.
      
Keywords: Celiac Disease; environmental factors; tolerance to gluten