title: Indirect costs of inflammatory bowel diseases: Crohn's disease and ulcerative colitis. A systematic review.
abstract: BACKGROUND
  Crohn's disease and ulcerative colitis are lifelong illnesses which have a significant impact on quality of life and personal burden through a reduction in the ability to work, sick leave and restrictions of leisure time. The aim of this study was to conduct a systematic review of the indirect costs of Crohn's disease and ulcerative colitis.
  
  
  METHODS
  The search was carried out in Medline, EMBASE, the Centre for Reviews and Dissemination, and reference lists of identified articles and reference lists of identified articles were also handsearched. All costs were adjusted to 2013 USD values by using the consumer price index and purchasing power parity. Identified studies were then analysed in order to assess their heterogeneity and possibility of inclusion in the meta-analysis.
  
  
  RESULTS
  Eleven of the identified publications presented indirect costs of Crohn's disease or ulcerative colitis. The range of estimated yearly indirect costs per patient was large, from $1 159.09 for loss of earnings to $14 135.64 for lost productivity and sick leave for Crohn's disease. The values for ulcerative colitis ranged from $926.49 to $6 583.17. Because of the imprecise definition of methods of indirect cost calculations as well as heterogeneity of indirect cost components, a meta-analysis was not performed.
  
  
  CONCLUSIONS
  The indirect costs of ulcerative colitis seem to be slightly lower than in the case of Crohn's disease. A small number of studies referring to indirect costs of Crohn's disease and ulcerative colitis were identified, which indicates the need to conduct further investigations on this problem.
authors.affiliation: Drug Management Department, Institute of Public Health, Faculty of Health Sciences, Jagiellonian University Medical College, Krakow, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Kawalec
keywords: Crohn's disease; indirect costs; productivity loss; ulcerative colitis