title: Idiopathic intracranial hypertension: a comparison between French and North-American white patients.
abstract: OBJECTIVE
  To compare French and American white patients with idiopathic intracranial hypertension (IIH), and to determine prognostic factors associated with visual loss.
  
  
  METHODS
  Medical records of all consecutive white patients with definite IIH seen between 2001 and 2006 in three French tertiary care medical centers and one American tertiary medical center were reviewed. Demographics, associated clinical features, and visual function at presentation and follow-up were collected. French white patients were compared to American white patients.
  
  
  RESULTS
  One hundred and thirty-four patients (66 French, 68 American) were included. American patients were 8.7 times more likely than French patients to have visual acuity 20/60 or worse or visual field constriction (95% CI: 2.1-36.1, p=0.0001). American patients were treated more aggressively than French patients. French patients were older (31 vs. 28 years, p=0.02) and more likely to have anemia (20 vs. 2%, p<0.001). American patients had a longer duration of symptoms prior to diagnosis (12 vs. 4 weeks, p=0.01) and longer follow-up than French patients (26 vs. 11 months, p=0.001). Multivariable analysis found that nationality was an independent risk factor for visual loss. French and American patients did not differ regarding gender proportion, frequency of obesity, sleep apnea, endocrine diseases, or systemic hypertension. Cerebrospinal fluid (CSF) opening pressures were similar in both groups.
  
  
  CONCLUSIONS
  American patients with IIH had worse visual outcomes than French patients despite more aggressive treatment. These differences are not explained by differences in previously known risk factors.
authors.affiliation: Department of Ophthalmology, hôpital Lariboisière, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Mrejen
authors.forename: C
authors.initials: C
authors.lastname: Vignal
authors.forename: B B
authors.initials: BB
authors.lastname: Bruce
authors.forename: R
authors.initials: R
authors.lastname: Gineys
authors.forename: F
authors.initials: F
authors.lastname: Audren
authors.forename: P
authors.initials: P
authors.lastname: Preechawat
authors.forename: A
authors.initials: A
authors.lastname: Gaudric
authors.forename: O
authors.initials: O
authors.lastname: Gout
authors.forename: N J
authors.initials: NJ
authors.lastname: Newman
authors.forename: A
authors.initials: A
authors.lastname: Vighetto
authors.forename: M-G
authors.initials: MG
authors.lastname: Bousser
authors.forename: V
authors.initials: V
authors.lastname: Biousse
mesh_terms: D000293:Adolescent; D000328:Adult; D001835:Body Weight / Q000502:physiology; D015170:Cerebrospinal Fluid Pressure / Q000502:physiology; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D019586:Intracranial Hypertension / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009656:North America / Q000453:epidemiology; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D014786:Vision Disorders / Q000453:epidemiology / Q000209:etiology; D014787:Vision Tests; D014792:Visual Acuity; D044465:White People; D055815:Young Adult