title: The age-related incidences of oesophageal carcinoma in intellectually disabled individuals in institutes in The Netherlands.
abstract: OBJECTIVE
  An increased age-related incidence of oesophageal cancer in people with intellectual disability has been suggested by studies in the Netherlands. Gastro-oesophageal reflux disease (GORD), as documented by pH testing, occurs frequently in the intellectually disabled population, being found in nearly 50% of those with an IQ less than 50, while Barrett's oesophagus is found in about 15-26%.
  
  
  METHODS
  We compared the age-related incidence of oesophageal cancer in institutionalized, intellectually disabled individuals in the Netherlands with the age-related incidence in the general Dutch population.
  
  
  METHODS
  Data were provided by the Netherlands Cancer Registry. The patient's institute physician was asked to complete a questionnaire about the diagnosis, which was endoscopically and histologically confirmed.
  
  
  RESULTS
  The incidence of oesophageal carcinoma was 20 in 168,000 person-years. The expected incidence for oesophageal cancer, based on age-related incidence in the general population, was 7.0, resulting in a standardized morbidity ratio in the population with intellectual disability of 2.9 (confidence limits, 1.8-4.1; P < 0.001). Endoscopic findings were as follows: in 18/20 intellectually disabled carcinoma patients an adenocarcinoma was found; the remaining two patients had a squamous cell carcinoma. Barrett's epithelium was observed in nine patients (45%), eight (42%) of whom showed a peptic stricture as well. In 15 (75%) cancer patients reflux oesophagitis was found, accompanied in 14 cases by a hiatal hernia.
  
  
  CONCLUSIONS
  A standardized morbidity ratio for oesophageal carcinoma of 2.9 was found in the intellectually disabled population as compared to the general population. Early detection and treatment of GORD in the population with intellectual disability is of paramount importance to prevent the development of Barrett's dysplasia and carcinoma.
authors.affiliation: Bartiméus Institute for Intellectually Disabled, Zeist, The Netherlands.
authors.forename: C J
authors.initials: CJ
authors.lastname: Böhmer
authors.forename: E C
authors.initials: EC
authors.lastname: Klinkenberg-Knol
authors.forename: R C
authors.initials: RC
authors.lastname: Niezen-de Boer
authors.forename: S G
authors.initials: SG
authors.lastname: Meuwissen
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000453:epidemiology*; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D016001:Confidence Intervals; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008607:Intellectual Disability / Q000453:epidemiology*; D008297:Male; D008605:Mental Health Services / Q000706:statistics & numerical data; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors