ABSTRACT
OBJECTIVE: Headache and insomnia are both very common and burdensome complaints worldwide. Numerous articles have been written on the relation between them, but the number of scientific articles is limited. The purpose of this review is to summarize the current scientific literature and analyze it in light of the nature of the headache-insomnia relation. METHODS: An extensive literature search was conducted using the terms, headache, migraine, insomnia, sleep, sleep deprivation, and sleep loss, on the search engines PubMed, ScienceDirect, Medline, and Google Scholar. A total of twelve research articles were found, discussing the relation of insomnia to headache in general, tension-type headache, migraine, and chronic headache. The majority of the studies are cross-sectional but two are longitudinal. RESULTS: The studies suggest an association between headache and insomnia but an asymmetrical one, with headache being more associated with insomnia than the other way around. Therefore, in the association of headache and insomnia, other factors associated with headache or migraine probably play a role, as well. CONCLUSION: As insomnia appears to be a risk factor for headache or migraine onset, insomnia patients should probably be routinely evaluated for headache. As it also seems a risk factor for increased headache frequency, in particular in tension headache and migraine, patients with these conditions should probably be routinely treated for insomnia, if present, as part of their overall management.