Kim J, et al. - This population-based study assessed the prevalence and effect of insomnia among individuals with tension-type headache (TTH) using data from the Korean Headache-Sleep Study (KHSS). The authors demonstrated that among individuals with TTH, insomnia was prevalent. Insomnia was also correlated with exacerbation of headache symptoms and psychiatric comorbidities. Thus, identification of insomnia among individuals with TTH was required to improve the management of headache symptoms in such patients.

• Data was examined from the KHSS—a nation-wide, cross-sectional, population-based survey on headache and sleep involving Korean adults aged 19 to 69 years.
• The authors defined insomnia as an Insomnia Severity Index score ≥ 10.

• The authors classified 570 (21.2%) and 290 (10.8%) as having TTH and insomnia, respectively, among 2695 participants.
• For probable migraine (PM), 113 (19.8%) met the criteria, among individuals with TTH.
• Among individuals with TTH, the prevalence of insomnia was significantly higher than that among individuals without headache (13.2% vs. 5.8%, p < 0.001).
• Among the TTH group, however, the prevalence of insomnia did not significantly differ between participants fulfilling PM criteria and those not fulfilling PM criteria (14.2% vs. 12.9%, p = 0.725).
• Headache frequency [median and interquartile range (IQR): 1.0 (0.3-3.0) vs. 0.4 (0.2-1.0), p = 0.002], visual analogue scale scores for headache intensity [median and IQR: 5.0 (4.0-7.0) vs. 4.0 (3.0-6.0), p < 0.001], Headache Impact Test-6 scores [median and IQR: 46.0 (40.0-52.0) vs. 42.0 (38.0-46.0), p < 0.001], anxiety prevalence (28.0% vs. 6.7%, p < 0.001), and depression prevalence (21.3% vs. 1.6%, p < 0.001) were significantly higher in those with insomnia than in those without insomnia among individuals with TTH.