Characterization of insomnia and sleep quality in a cohort with cluster headache

Abstract

Objective: The objective of this cross-sectional study was to investigate the extent of perceived sleep disturbances in a cluster headache cohort, and to compare how sleep is perceived between participants in an active headache bout to participants in a headache-free remission period.

Background: Cluster headache is a primary headache disorder characterized by extremely painful headache attacks. These attacks commonly occur with a circadian rhythm, with a majority of patients experiencing nocturnal attacks. Sleep is affected in patients with cluster headache, but there are many uncertainties regarding the pathophysiological connection between cluster headache and sleep disturbances and to what extent sleep disturbances persist into remission.

Methods: A digital survey was sent out to 701 individuals with cluster headache between January and May 2024. The survey contained questions regarding general health, clinical cluster headache phenotype, and questions from the Karolinska Sleep Questionnaire, the Insomnia Severity Index, and the Dysfunctional Beliefs and Attitudes about Sleep-10. Scores extracted from each questionnaire were compared between study participants in an active bout versus study participants in remission, and study participants in short-term remission (<5 years) versus long-term remission (≥5 years).

Results: Of the 381 individuals who answered the survey, 325 were included in the final analysis. Participants in an active cluster headache bout reported increased sleep disturbances on all measurements compared to participants in remission (insomnia severity: adjusted odds ratio [aOR] = 1.12 [95% confidence interval (CI), 1.07-1.17] p < 0.001; sleep quality: aOR = 0.67 [95% CI, 0.53-0.83] p < 0.001; daytime sleepiness: aOR = 0.59 [95% CI, 0.44-0.78] p < 0.001; and dysfunctional beliefs: aOR = 1.03 [95% CI, 1.01-1.04] p = 0.001). Of the participants in an active bout, 46.5% scored above the Insomnia Severity Index threshold indicating moderate to severe insomnia (≥15) and 43.7% were considered as having poor sleep quality (≤3 on the Sleep Quality Index extracted from the Karolinska Sleep Questionnaire). This is in comparison to 22.0% of participants in remission being above the moderate insomnia threshold and 22.0% considered having poor sleep quality. Participants in long-term remission had better sleep scores overall compared to participants in short-term remission (insomnia severity: aOR = 1.09 [95% CI, 1.03-1.16] p = 0.005; daytime sleepiness: aOR = 0.67 [95% CI, 0.42-1.02] p = 0.072; and dysfunctional beliefs: aOR = 1.03 [95% CI, 1.01-1.05] p = 0.006).

Conclusion: Individuals with cluster headache have a large degree of sleep disturbances that are exacerbated during an active bout and not completely alleviated during remission. Future studies are needed to determine if this gradual change in sleep disturbances after an active bout is due to physiological changes, which slowly revert to baseline levels after an active bout or connected to persisting negative behavioral or cognitive associations between sleep and headache.

Keywords: Dysfunctional Beliefs and Attitudes about Sleep‐10; Insomnia Severity Index; Karolinska Sleep Questionnaire; Sleep Quality Index; dysfunctional beliefs; sleepiness.

FIGURE 1

Flow diagram showing recruitment, inclusion, and exclusion of study participants. A total of 701 individuals were contacted by email for inclusion in the study. Of those, 320 were excluded due to nonresponse to our email, and 56 were excluded due to low completion rate, not filling out the consent form, or having the wrong diagnosis. In total, 325 study participants were included in the final analysis. [Colour figure can be viewed at wileyonlinelibrary.com]

FIGURE 2

Scatterplot illustrating the relationship between SQI, Sleepiness Index, ISI, and DBAS‐10 scores to the number of years since last cluster headache bout (remission duration). Illustration of associations between sleep scores and cluster headache remission duration. The duration of remission was winsorized between 0 (<1 year) and 15 (97th percentile) years since last bout. Regression lines (for illustration purpose only) show the model fitting subjects 52 years old (average age in our cohort) and having no comorbidities (most common in our cohort), for males (blue) and females (pink), respectively. SQI: range 1–6, low score indicates poor quality sleep; Sleepiness Index: daytime sleepiness (range 1–6, low score indicates more daytime sleepiness) are calculated based on questions from the Karolinska Sleep Questionnaire; ISI: range 0–28, high score indicates more severe insomnia symptoms; DBAS‐10: range 0–100, high score indicates more dysfunctional beliefs. Abbreviations: DBAS‐10, Dysfunctional Beliefs and Attitudes about Sleep‐10; ISI, Insomnia Severity Index; SQI, Sleep Quality Index. [Colour figure can be viewed at wileyonlinelibrary.com]