title: Nationwide Incidence of Normal Pressure Hydrocephalus (NPH) Assessed by Insurance Claim Data in Germany.
abstract: BACKGROUND
  The purpose of this study is to investigate the epidemiology of the idiopathic normal pressure hydrocephalus (iNPH) in Germany.
  
  
  METHODS
  The database of the nationwide Barmer Health Insurance was queried for specific combinations of corresponding International Classification of Diseases, Ninth Revision (ICD-9) codes and OPS codes (German modification of the ICPM and official classification of surgical procedures) in order to assess the number of patients treated for iNPH and the number surgical procedures associated with the disease in a 10 years period between 2003 and 2012.
  
  
  RESULTS
  Between 2003 and 2012, the incidence of iNPH increased from zero to 1.36/100.000/year.
  
  
  CONCLUSIONS
  This is the first population-based epidemiologic study on iNPH in Germany covering a ten year period.
authors.affiliation: Department of Neurosurgery, Unfallkrankenhaus Berlin, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Lemcke
authors.affiliation: Center for Clinical Research, Department of Trauma and Orthopedic Surgery, Unfallkrankenhaus Berlin, Germany; Julius Wolff Institute, Charité Medical University Center, Berlin, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Stengel
authors.affiliation: Department of Neurosurgery, Georg August University of Göttingen, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Stockhammer
authors.affiliation: Center for Clinical Research, Department of Trauma and Orthopedic Surgery, Unfallkrankenhaus Berlin, Germany.
authors.forename: Claas
authors.initials: C
authors.lastname: Güthoff
authors.affiliation: Department of Neurosurgery, Georg August University of Göttingen, Germany.
authors.forename: Veit
authors.initials: V
authors.lastname: Rohde
authors.affiliation: Department of Neurosurgery, Unfallkrankenhaus Berlin, Germany.
authors.forename: Ullrich
authors.initials: U
authors.lastname: Meier
keywords: Epidemiology; Incidence; Normal pressure hydrocephalus; Shunt surgery