Is there a link between headache and cognitive disorders? A systematic review.

BACKGROUND: The overall prevalence of headaches decreases with age; however headaches remain frequent in aged individuals who are also affected by other disorders such as cognitive decline. Despite the high frequency of both conditions in these persons, the association between headaches and cognitive decline is underexplored, underdiagnosed and poorly understood. OBJECTIVE: In the present article, we aim to provide a comprehensive review of existing data concerning the link between headache and cognitive decline. METHODS: We undertook a systematic literature review to report articles that focus on headaches (including all types of headaches) and neurocognitive disorders of degenerative causes. RESULTS: Only 9 studies have explored the association between headaches and neurocognitive decline. Methods were highly variable from population-based study to short series of patients using either database or questionnaire during consultation. Studies focusing on Familial Alzheimer's Disease revealed a very high prevalence of headaches in mutation carrier patients compared to non-carrier patients. CONCLUSION: The association between headaches and cognitive decline is underexplored. Future studies are needed to address the pathophysiological mechanisms to improve the treatment of these underestimated headaches.