title: Immunological comorbity in coeliac disease: associations, risk factors and clinical implications.
abstract: OBJECTIVE
  Coeliac disease is frequently associated with other immunomediated diseases. Our aim was to identify immunological comorbidities and possible risk factors for their development in coeliac patients.
  
  
  METHODS
  We recruited a cohort of 1,015 coeliac patients followed from 0 to 46 years in a single tertiary referral centre. Data were collected from the yearly scheduled clinical and serological evaluations. Possible risk factors such as demographic parameters, type of symptomatic presentation, gluten exposure, gluten-free diet compliance and family history were all evaluated. Subjects (848,606) from the regional health registry were investigated as controls.
  
  
  RESULTS
  The prevalence of immunomediated diseases was higher in patients with coeliac disease compared to the registry population (23 % vs 0.4 %, p < 0.001). Diagnosis during paediatric age represented a risk factor for the presence of at least an immunomediated disease (hazard ratio = 1.62, 95 % confidence interval 1.15-2.29, p = 0.0061). Type of presentation and dietetic compliance did not represent risk factors. Long-standing gluten exposure reduced the risk of developing immunomediated diseases in coeliac subjects (hazard ratio for 1 year longer exposure 0.23, 95 % confidence interval 0.16-0.33, p < 0.0001). A familiar background characterized by the presence of immunological disorders was not a risk factor, although 419 (13 %) first degree relatives of coeliac patients out of 3,195 had an immunomediated disease.
  
  
  CONCLUSIONS
  Our study suggests the need to investigate coeliac patients for other associated immunomediated diseases, independently of sex, gluten exposure and compliance to therapy; also subjects diagnosed in paediatric age should be carefully screened during follow up.
authors.affiliation: Center for the Prevention and Diagnosis of Coeliac Disease, Fondazione IRCCS Cà Granda-Ospedale Maggiore Policlinico, Via F. Sforza 35, 20122, Milan, Italy. lucelli@yahoo.com
authors.forename: Luca
authors.initials: L
authors.lastname: Elli
authors.forename: Antonella
authors.initials: A
authors.lastname: Bonura
authors.forename: Daniela
authors.initials: D
authors.lastname: Garavaglia
authors.forename: Eliana
authors.initials: E
authors.lastname: Rulli
authors.forename: Irene
authors.initials: I
authors.lastname: Floriani
authors.forename: Giovanna
authors.initials: G
authors.lastname: Tagliabue
authors.forename: Paolo
authors.initials: P
authors.lastname: Contiero
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Bardella
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002446:Celiac Disease / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D005260:Female; D006801:Humans; D007154:Immune System Diseases / Q000453:epidemiology*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D055815:Young Adult