Migraine and light: A narrative review

Abstract

Objective In this narrative review, we summarize clinical and experimental data on the effect of light in migraine and discuss future prospects. Background Effective nonpharmacological treatment of hypersensitivity to light in migraine is an unmet clinical need. Current management strategies primarily consist of seeking a dark room and avoiding light exposure. Advances in the past 2 decades have improved our understanding of the underlying pathophysiology of how migraine is influenced by light. This may provide promising avenues for novel approaches in clinical management. Methods We searched MEDLINE for articles published from database inception up to September 1, 2021. We used the search term “migraine” with the search terms “light,” “photophobia,” “treatment,” “trigger,” “circadian rhythm,” “environment,” and/or “pathophysiology.” Results Light is commonly reported as a trigger factor of migraine attacks, however, early manifestation of photophobia and false attribution is likely the actual cause based on data deriving from retrospective, prospective, and experimental studies. The most common photophobia symptoms in migraine are exacerbation of headache by light and abnormal sensitivity to light with the underlying neural pathways likely being dependent on ongoing activity in the trigeminovascular system. Clinical studies and experimental models have identified mediators of photophobia and uncovered narrow wavebands of the light spectrum that may reduce pain intensity during a migraine attack. Consequently, novel devices have undergone exploratory clinical trials with promising results. Conclusion False attribution is likely the reason why light is commonly reported as a trigger factor of migraine attacks, and a prospective confirmation is required to prevent unnecessary avoidance. The observation that individuals with migraine are not equally photophobic to all wavebands of the light spectrum opens the potential for innovative pain management strategies. In this context, using human‐centric lighting (also called integrative lighting) to mimic the natural daylight cycle and avoid harmful wavebands through modern technology may prove beneficial. Future research should identify direct and indirect consequences of light and other environmental factors in migraine to fill out knowledge gaps and enable evidence‐based care strategies within institutions, work environments, and other settings.

Triggers of migraine: where do we stand?

“…These observations can explain photophobia, a defining feature of migraine. According to Artemenko et al [37 ▪▪ ], photophobia comprehends three main defining characteristics: exacerbation of headache by light, photo-oculodynia and abnormal sensitivity to light. All of them highlight the strong relationship existing between the trigeminovascular system, the pulvinar and the occipital cortex.…”

The effect of bright light therapy in migraine patients with sleep disturbance: A prospective, observational cohort study protocol

“…Bright light therapy (BLT) can reportedly improve nighttime sleepiness due to circadian rhythm or neuro-psychiatric disorders and sleep duration and reduce daytime sleepiness ( Burkhalter et al, 2015 ; Faulkner et al, 2019 ); however, the effect of BLT in migraine patients with sleep disturbance is uncertain. Particularly, light has been viewed as a trigger for migraine, but a recent review reported that migraine patients are not photophobic to all wavebands of the light spectrum ( Artemenko et al, 2022 ). Thus, light therapy should be an innovative approach.…”

Avoid or seek light – a randomized crossover fMRI study investigating opposing treatment strategies for photophobia in migraine

“…Exposure to flickering light for instance, is also reported as a trigger for migraine attacks. Up to 69% of the patients identify visual discomfort as a precipitating factor for their attacks [ 5 ]. The standard advice to avoid migraine attacks has been to identify and to avoid triggers.…”

“…Fig 5. Correlations between primary visual cortex (V1) activation habituation estimates and diary variables in the patients.…”