title: Clinical course and costs of care for Crohn's disease: Markov model analysis of a population-based cohort.
abstract: OBJECTIVE
  Crohn's disease results in substantial morbidity and high use of health services. The aim of this study was to describe the lifetime clinical course and costs of Crohn's disease in a 24-year population-based inception cohort of patients with Crohn's disease in Olmsted County, Minnesota.
  
  
  METHODS
  Disease states were defined by medical and surgical treatment. A Markov model analysis calculated time in each disease state and present value of excess lifetime costs in comparison with an age- and sex-matched cohort.
  
  
  RESULTS
  For a representative patient, projected lifetime costs were $39,906 per patient using median charges and $125,404 using mean charges. There were 29.1 years (63% of total) without medications. There were 12.7 years (27%) on aminosalicylate therapy, generating $11,467 (29%) in charges, and 3.2 years (7%) on corticosteroid or immunosuppressive therapy, generating $5147 (13%) in charges. Surgery generated $17,526 (44%) in charges.
  
  
  CONCLUSIONS
  Most of the clinical course is spent in remission, either medical or surgical. Aminosalicylate therapy accounts for 29% of the costs of care. Surgery has the highest charges but the longest remissions. Treatment strategies that induce remission in mild disease and maintain remission with lower-cost maintenance therapy will have the largest effect on patient outcomes and costs.
authors.affiliation: Division of Area General Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA. silverstein.marc@musc.edu
authors.forename: M D
authors.initials: MD
authors.lastname: Silverstein
authors.forename: E V
authors.initials: EV
authors.lastname: Loftus
authors.forename: W J
authors.initials: WJ
authors.lastname: Sandborn
authors.forename: W J
authors.initials: WJ
authors.lastname: Tremaine
authors.forename: B G
authors.initials: BG
authors.lastname: Feagan
authors.forename: P J
authors.initials: PJ
authors.lastname: Nietert
authors.forename: W S
authors.initials: WS
authors.lastname: Harmsen
authors.forename: A R
authors.initials: AR
authors.lastname: Zinsmeister
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015331:Cohort Studies; D003424:Crohn Disease / Q000188:drug therapy / Q000601:surgery / Q000628:therapy*; D005260:Female; D017048:Health Care Costs; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity