Impact of migraine on the clinical presentation of insomnia: a population-based study

Background: Insomnia and migraine are closely related; insomnia aggravates migraine symptoms. This study was conducted to investigate the impact of migraine on the clinical presentation of insomnia symptoms. Methods: The data of the Korean Headache-Sleep Study (KHSS) were used in the present study. The KHSS is a nation-wide cross-sectional population-based survey regarding headache and sleep in Korean adults aged 19 to 69 years. If a participant's Insomnia Severity Index (ISI) score 10, she/he was classified as having insomnia. The clinical presentation of insomnia symptoms was assessed using total and subcomponent scores of the ISI. Results: Of 2695 participants, 290 (10.8%) and 143 (5.3%) individuals were assigned as having insomnia and migraine, respectively. The proportions of migraine (12.8% vs. 4.4%, p < 0.001) and non-migraine headache (59.0% vs. 39.9%, p < 0.001) were higher among individuals with insomnia compared to those without insomnia. Among participants with insomnia, total 151 scores were not significantly different among participants with migraine, non-migraine, and non-headache [median and interquartile range: 13.0 (11.0-17.5) vs. 13.0 (11.0-17.5) vs. 12.0 (11.0-16.0), p = 0.245]. ISI scores for noticeability of sleep problems to others were significantly higher among participants with migraine [3.0 (2.0-4.0) vs. 2.0 (2.0-3.0), p = 0.011] and non-migraine headache [3.0 (2.0-4.0) vs. 2.0 (2.0-3.0), p = 0.001] compared to those without headache history. Other ISI subcomponent scores did not significantly differ between headache status groups. Conclusions: Participants with insomnia had an increased risk of migraine and non-migraine headache compared to those without insomnia. Among participants with insomnia, overall insomnia severity was not significantly influenced by the headache status.