Relating Photophobia, Visual Aura, and Visual Triggers of Headache and Migraine.

OBJECTIVE: This study investigated a potential association between visual factors and symptoms related to migraine. It was predicted that photophobia and visual aura would be positively associated with interictal light sensitivity and visual headache triggers (flicker, glare, and eyestrain), and that these 2 visual symptoms would also be associated.

BACKGROUND: Previous studies have found independent neurophysiological associations between several visual factors and symptoms related to headache disorders. Many of these connections appear to be associated with increased cortical hypersensitivity, a phenomenon that might be in part due to repeated avoidance and reduced tolerance to triggers. If true, and if associations between visual factors and symptoms can be established, this may have implications for an exposure-based treatment for migraine symptoms.

METHODS: Four hundred and ninety-one participants (411 female, 80 male) were recruited through Griffith University (AUS), Headache Australia, Pain Australia, and through social media. Participants were grouped based on the presence of headache disorder symptoms and the presence or absence of photophobia and/or visual aura. A cross-sectional online survey design was utilized to gather information pertaining to interictal light sensitivity, visual triggers, and visual symptoms.

RESULTS: With respect to interictal light sensitivity and photophobia, a significant difference (P < .001, eta squared [η2 ] = 0.084) was found between the 3 groups, where headache disorder participants with photophobia (group A1; mean [M] = 2.5, standard deviation [SD] = 0.97) reported significantly greater light sensitivity than participants with headache disorder and no photophobia (A2; M = 1.68, SD = 0.62) and control group participants (A3; M = 1.82, SD = 0.85). This pattern was repeated for participants reporting flicker as a headache trigger (P < .001, η2 = 0.061), with group A1 (M = 2.45, SD = 1.24) significantly higher than groups A2 (M = 1.68, SD = 0.83) and A3 (M = 1.68, SD = 0.89), and was also seen for glare as a headache trigger (P < .001, η2 = 0.092), with group A1 (M = 2.92, SD = 0.96) significantly higher than A2 (M = 2.31, SD = 0.89) and A3 (M = 2.09, SD = 0.93). This pattern of results was not replicated for headache disorder participants with and without visual aura. A significant association (P < .001) was found between photophobia and visual aura in headache disorder participants based on a chi-square test of independence, with 86/136 participants reporting either both or neither visual symptom.

CONCLUSIONS: This study supports a link between certain visual phenomena in headache disorder populations, and supports future research into exposure-based treatments for migraine symptoms.