title: Predictors of gallstone composition in 1025 symptomatic gallstones from Northern Germany.
abstract: BACKGROUND
  Gallstones represent a prevalent and costly health problem. The changing epidemiology and the emerging non-surgical interventions for gallstone disease necessitate the definition of target populations for future therapies. This study aimed to define patterns of gallstone composition and identify demographic predictors of gallstone composition in a large sample of symptomatic gallstones from Northern Germany.
  
  
  METHODS
  One thousand and seventy-four post-cholecystectomy gallstone specimens were obtained. Demographic and clinical information was provided by questionnaire (N = 1025 independent individuals with complete information). Two samples from each gallstone were analyzed using Fourier transformed infrared spectrometry.
  
  
  RESULTS
  The most prevalent substance was cholesterol, which was detected in 95.0% of gallstone specimens. Bilirubin and bilirubinate were present in 30.0% and calcium was detected in 10.0% of the spectra. Ninety-two percent of measurements from the same stone yielded the same "main" substances, indicating a homogenous stone composition in most cases. Female sex and higher body mass index (BMI) were associated with the presence of cholesterol as a main substance in the gallstones (p < 0.001).
  
  
  CONCLUSIONS
  The changing epidemiology of gallstone disease is reflected by a marked shift in stone composition: Only two percent of stones in this study were pigment stones as compared to 91% percent of stones containing cholesterol as a main substance. Obese individuals from Germany with a BMI > 30 kg/m2 have in 95% cholesterol-dominant gallstones and represent a potential target population for non-surgical interventions for the prevention or treatment of cholesterol stones.
authors.affiliation: Department of General and Thoracic Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str. 7, D-24105 Kiel, Germany. cschafmayer@chirurgie-sh.de <cschafmayer@chirurgie-sh.de>
authors.forename: Clemens
authors.initials: C
authors.lastname: Schafmayer
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hartleb
authors.forename: Jürgen
authors.initials: J
authors.lastname: Tepel
authors.forename: Stefan
authors.initials: S
authors.lastname: Albers
authors.forename: Sandra
authors.initials: S
authors.lastname: Freitag
authors.forename: Henry
authors.initials: H
authors.lastname: Völzke
authors.forename: Stephan
authors.initials: S
authors.lastname: Buch
authors.forename: Markus
authors.initials: M
authors.lastname: Seeger
authors.forename: Birgit
authors.initials: B
authors.lastname: Timm
authors.forename: Bernd
authors.initials: B
authors.lastname: Kremer
authors.forename: Ulrich R
authors.initials: UR
authors.lastname: Fölsch
authors.forename: Fred
authors.initials: F
authors.lastname: Fändrich
authors.forename: Michael
authors.initials: M
authors.lastname: Krawczak
authors.forename: Stefan
authors.initials: S
authors.lastname: Schreiber
authors.forename: Jochen
authors.initials: J
authors.lastname: Hampe
mesh_terms: D000367:Age Factors; D001654:Bile Pigments / Q000032:analysis; D001663:Bilirubin / Q000032:analysis; D015992:Body Mass Index; D002118:Calcium / Q000032:analysis; D002763:Cholecystectomy; D002784:Cholesterol / Q000032:analysis; D005260:Female; D042882:Gallstones / Q000737:chemistry* / Q000145:classification / Q000453:epidemiology / Q000473:pathology; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D017678:Sex Distribution; D012737:Sex Factors; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001654:Bile Pigments; D002784:Cholesterol; D001663:Bilirubin; D002118:Calcium