title: Is the association between irritable bowel syndrome and abuse explained by neuroticism? A population based study.
abstract: BACKGROUND
  In outpatients and the community, an association between abuse (particularly sexual abuse) and irritable bowel syndrome (IBS) has been observed, but whether there is a causal link continues to be disputed.
  
  
  OBJECTIVE
  To test the hypothesis that psychological factors explain the apparent association between abuse and IBS.
  
  
  METHODS
  A sample of residents of Penrith (a Sydney suburb sociodemographically similar to the Australian population) selected randomly from the electoral rolls (that by law include the entire population of age 18 years and above) was mailed a validated self report questionnaire. Measured were gastrointestinal (GI) symptoms including the Rome criteria for IBS, abuse (including the standardised Drossman questions), neuroticism (Eysenck Personality Questionnaire), and psychological morbidity (General Health Questionnaire).
  
  
  RESULTS
  The response rate was 64% (n = 730); 12% fulfilled the Rome criteria for IBS. Overall abuse in childhood (odds ratio (OR) = 2.02, 95% confidence interval (CI) 1.29 to 3.15) but not adulthood (OR = 1.39, 95% CI 0.88 to 2.19) was associated with IBS univariately. Neuroticism and psychological morbidity were also univariately associated with abuse in childhood, abuse in adulthood and IBS, respectively. However, by logistic regression, abuse in childhood was not associated with IBS after controlling for age, gender, and psychological factors (OR = 1.34, 95% CI 0.83 to 2.17). The results were not altered by restricting the analyses to more severe forms of abuse, and were not explained by interactions between abuse and psychological variables.
  
  
  CONCLUSIONS
  There is an association between abuse and IBS in the community, but this may be explained in part by other psychological factors. Based on a path analysis, we postulate that abuse may induce the expression of neuroticism that in turn leads to IBS.
authors.affiliation: Department of Medicine, University of Sydney, Nepean Hospital, Penrith, NSW, Australia.
authors.forename: N J
authors.initials: NJ
authors.lastname: Talley
authors.forename: P M
authors.initials: PM
authors.lastname: Boyce
authors.forename: M
authors.initials: M
authors.lastname: Jones
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002649:Child Abuse; D002650:Child Abuse, Sexual; D003109:Colonic Diseases, Functional / Q000209:etiology* / Q000523:psychology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009497:Neurotic Disorders / Q000150:complications*; D010554:Personality Disorders / Q000150:complications; D011569:Psychiatric Status Rating Scales; D011795:Surveys and Questionnaires; D014754:Violence