title: Biliary dyskinesia: a surgical disease rarely found outside the United States.
abstract: BACKGROUND
  Our objective was to determine if cholecystectomy for biliary dyskinesia (BD) was performed more commonly in the United States than in 4 comparator countries around the world.
  
  
  METHODS
  Using the Nationwide Inpatient Sample, we extracted and analyzed data for cholecystectomy from 1991 to 2011 using ICD-9 (International Classification of Diseases 9th Revision) procedure codes. To derive the number of cholecystectomies performed for BD, we used the ICD-9 code 575.8, greater than 80% of which are patients with BD. The same or equivalent code was used for the international comparator group. Through a SURGINET query we obtained data from verifiable national databases in 4 developed countries including the Swedish quality registry for surgical treatments of gallstone-related conditions (GallRiks), the Norwegian Cholecystectomy Registry, the Australian Bureau of Statistics, and the Polish National Health Insurance Agency.
  
  
  RESULTS
  In the years ranging from 2008 to 2011, the number of cholecystectomies for BD per 1,000,000 population per year was less than 25 in the 4 comparator countries and greater than 85 in the United States (P < .01). From 1991 to 2011, the number of cholecystectomies for BD in the United States significantly increased from 43.3 to 89.1 per 1,000,000 population (P < .01).
  
  
  CONCLUSIONS
  These data strongly suggest that cholecystectomy for BD is over utilized in the United States. In addition, this trend continues to increase in frequency.
authors.affiliation: Department of Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA. Electronic address: jennifer.f.preston@gmail.com.
authors.forename: Jennifer F
authors.initials: JF
authors.lastname: Preston
authors.affiliation: Department of Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Diggs
authors.affiliation: Department of Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Dolan
authors.affiliation: Department of Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
authors.forename: Erin W
authors.initials: EW
authors.lastname: Gilbert
authors.affiliation: Department of Surgery, Marshfield Clinic, Marshfield, WI, USA.
authors.forename: Moshe
authors.initials: M
authors.lastname: Schein
authors.affiliation: Department of Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
authors.forename: John G
authors.initials: JG
authors.lastname: Hunter
mesh_terms: D001657:Biliary Dyskinesia / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D002763:Cholecystectomy / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D014943:Global Health; D006801:Humans; D015994:Incidence; D008297:Male; D015995:Prevalence; D012042:Registries; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology
keywords: Biliary dyskinesia; Cholecystectomy; Gallbladder dysfunction; Gallbladder dyskinesia