Cluster headache in Asian populations: Similarities, disparities, and a narrative review of the mechanisms of the chronic subtype

Objective: Headache disorders like migraine show geographic and ethnic differences between Asian and European/North American countries. In cluster headache, these differences are rarely mentioned and discussed. This article aimed to review the characteristics of cluster headache in Asian countries and compare the clinical features to those in European and North American populations. Methods: We conducted a narrative literature review on the demographics, clinical presentations, and treatments of cluster headache in Asian countries. Results: Patients with cluster headache in Asian populations showed a stronger male predominance compared to European and North American populations. Chronic cluster headache was rare in Asian countries. The clinical presentation of restlessness was not as common in Asian as it was in European and North American countries, and Asian patients with aura were extremely rare. Patients in Asian countries may have a lower circadian rhythmicity of cluster headache and a lower headache load, as demonstrated by lower attack frequencies per day, bout frequencies, and bout durations. Conclusions: Regional differences in the presentation of cluster headache exist. Greater awareness for cluster headache should be raised in Asian regions, and further studies are warranted to elucidate the mechanisms behind observed differences.