title: Microscopic colitis: a large retrospective analysis from a health maintenance organization experience.
abstract: OBJECTIVE
  To examine the demographic data on a large multi-ethnic population of patients with microscopic colitis (MC) in Southern California and to determine the association of MC with inflammatory bowel disease (IBD) and colorectal cancer.
  
  
  METHODS
  All patients diagnosed with MC by colonic biopsy from 1996-2005 were identified utilizing a pathology database. All biopsies were reviewed by experienced pathologists utilizing standard histologic criteria. Patients' medical records were reviewed and data regarding patient age, co-morbidities, sex, ethnicity, and medications were analyzed. An age- and sex-matched standard control group was also generated. Chi-square test was used to evaluate the associations of co-morbidities between lymphocytic colitis (LC), collagenous colitis (CC) and the control group.
  
  
  RESULTS
  A total of 547 cases of MC were identified, 376 patients with LC and 171 patients with CC. The female/male ratio was 3:1 in CC and 2.7:1 in LC patients. Celiac disease (P < 0.001), irritable bowel syndrome (IBS) (P < 0.001), and thyroid diseases (P < 0.001) were found to have a higher occurrence in MC compared to the control group. No statistical differences in the occurrence of colorectal cancer, diabetes and IBD were found between the MC group and the control group.
  
  
  CONCLUSIONS
  This is the largest group of patients with MC known to the authors that has been studied to date. Conditions such as celiac disease, IBS, and thyroid diseases were found to be related to MC. Furthermore, neither an increased risk of colorectal cancer nor IBD was associated with MC in this study.
authors: Department of Gastroenterology, Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA 90027, USA. kevin.t.kao@kp.org
authors: Kevin-T
authors: KT
authors: Kao
authors: Benito-A
authors: BA
authors: Pedraza
authors: Amy-C
authors: AC
authors: McClune
authors: David-A
authors: DA
authors: Rios
authors: Yi-Qiong
authors: YQ
authors: Mao
authors: Robert-H
authors: RH
authors: Zuch
authors: Michael-H
authors: MH
authors: Kanter
authors: Sony
authors: S
authors: Wirio
authors: Chris-N
authors: CN
authors: Conteas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California / Q000453:epidemiology / Q000208:ethnology; D046728:Colitis, Microscopic / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D015179:Colorectal Neoplasms / Q000473:pathology*; D015897:Comorbidity; D016208:Databases, Factual; D005006:Ethnicity; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult