title: Self-reported photophobic symptoms in migraineurs and controls are reliable and predict diagnostic category accurately.
abstract: OBJECTIVE
  To assess the reliability of self-reported photophobia across different patient populations and to examine how visual stress thresholds and photophobic symptoms may be predictive of diagnosis.
  
  
  BACKGROUND
  Relatively little is known about interictal photophobia in migraine. In particular, the variability of photophobia across different patient groups has not previously been studied, and a pathophysiological hypothesis to account for the symptoms is not agreed upon.
  
  
  RESULTS
  Study 1 compared 99 self-selected Dutch patients and 101 headache-free controls using survey methods. Patients both with and without aura were significantly more likely to report symptoms, such as the wearing of sunglasses in normal daylight, consistent with interictal photophobia. Study 2 replicated these findings in a series of consecutive referrals to a headache clinic in the United States. Study 3 used a specially designed laboratory test to examine the threshold for visual stress in those patients who had participated in study 2. Visual stress thresholds were significantly lower in patients than in controls. A discriminant function analysis of data from both studies 2 and 3 showed that diagnostic category (migraine; control) could be predicted from photophobic symptoms and visual stress thresholds at a level significantly better than chance.
  
  
  CONCLUSIONS
  We suggest that interictal photophobia is common in migraine and similar across different patient populations. One pathophysiological hypothesis is that interictal photophobia is associated with cortical hypersensitivity to stimulation. The predictive validity of interictal photophobic symptoms suggests that clinical diagnosis may be aided by questioning the patient about light sensitivity in the period between attacks.
authors.affiliation: Department of Neurology, Atrium Medical Center, PO Box 4446, 6401 CX Heerlen, The Netherlands.
authors.forename: W M
authors.initials: WM
authors.lastname: Mulleners
authors.forename: S K
authors.initials: SK
authors.lastname: Aurora
authors.forename: E P
authors.initials: EP
authors.lastname: Chronicle
authors.forename: R
authors.initials: R
authors.lastname: Stewart
authors.forename: S
authors.initials: S
authors.lastname: Gopal
authors.forename: P J
authors.initials: PJ
authors.lastname: Koehler
mesh_terms: D006801:Humans; D008881:Migraine Disorders / Q000175:diagnosis* / Q000503:physiopathology*; D020325:Migraine with Aura / Q000175:diagnosis / Q000503:physiopathology; D020326:Migraine without Aura / Q000175:diagnosis / Q000503:physiopathology; D009426:Netherlands / Q000453:epidemiology; D020795:Photophobia / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D015995:Prevalence; D015203:Reproducibility of Results; D012647:Self-Assessment; D012684:Sensory Thresholds; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014787:Vision Tests / Q000592:standards; D014796:Visual Perception