Shift work and migraine: A systematic review

OBJECTIVES: Migraine is a chronic neurological disorder characterized by recurrent attacks of headache, mainly affecting the working age population with a great socioeconomic impact. The etiology of migraine is still uncertain, and various individual and/or environmental risk factors have been suggested as triggers of the attacks, including irregularities in the sleep‐wake rhythm. In this perspective, it is possible that shift and night work, affecting circadian rhythms, may play a key function in the disease pathogenesis. Therefore, aim of this review was to provide an overview on the possible association between shift works and migraine development or clinical outcomes. METHODS: A systematic review of literature studies available in Pubmed, Scopus, and ISI Web of Science databases, addressing the possible shift work‐migraine relationship was performed. RESULTS: Conflicting data emerged from the revised studies. Some results supported a positive association between migraine prevalence and shift works, according to peculiar job tasks, seniority in shift works, specific work schedules, and number of night shifts performed in a month. However, other investigations failed to confirm such findings. CONCLUSIONS: The limited number of available studies, their cross‐sectional nature, the different criteria employed for migraine diagnosis, and the various shift work schedules analyzed, together with exposure to other confounding factors on workplace do not allow to extrapolate definite conclusions on shift work‐migraine relationship. From an occupational health perspective, further studies appear necessary to better understand such exposure‐disease association and possibly define risk assessment and management strategies to protect the health of susceptible and/or migraine affected workers.