title: Does idiopathic normal pressure hydrocephalus always mean a poor prognosis?
abstract: OBJECTIVE
  The objective was to assess whether idiopathic normal-pressure hydrocephalus (iNPH) has a worse prognosis than other forms of hydrocephalus, as has been suggested.
  
  
  METHODS
  A total of 125 patients with chronic hydrocephalus, 75 of whom suffered from iNPH and the remaining (non-INPH) from sNPH or non-communicating hydrocephalus, were shunted using gravitational valves. Clinical state was assessed with our clinical grading (KI) and a co-morbidity index (CMI). Average follow-up was 5.1 +/- 1.6 years.
  
  
  METHODS
  Spearman, Kruskal-Wallis, ANOVA, chi(2)- and the Wilcoxon U tests at a significance level of pi < 0.05 were used.
  
  
  RESULTS
  Shunt responder rates for iNPH and non-iNPH were 72% and 86%, respectively. With shorter anamnesis (< or =1 year) or preoperative KI < 6 points, iNPH patients had a similar or even better outcome than non-iNPH patients with longer anamnesis or a worse KI. Most impressive was the influence of co-morbidity: 86% of iNPH patients with a low CMI (< or =3 points) experienced clinical improvement after shunting, which was contrasted by a responder rate of 64% for non-iNPH with worse CMI.
  
  
  CONCLUSIONS
  The diagnosis of iNPH does not by itself mean a worse prognosis, and iNPH patients with favorable preconditions may have a similar or better prognosis than patients with any other kind of hydrocephalus. The worse overall clinical results of iNPH result from late recognition and in most instances worse preconditions.
authors.affiliation: Department of Neurosurgery, Saarland University Medical School, Homburg-Saar, Germany. Michael.Kiefer@uks.eu
authors.forename: Michael
authors.initials: M
authors.lastname: Kiefer
authors.forename: Ulrich
authors.initials: U
authors.lastname: Meier
authors.forename: Regina
authors.initials: R
authors.lastname: Eymann
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002557:Cerebrospinal Fluid Shunts / Q000379:methods*; D018450:Disease Progression; D005260:Female; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000175:diagnosis* / Q000601:surgery*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult