Clinical profile of cluster headaches in Japan: low prevalence of chronic cluster headache, and uncoupling of sense and behaviour of restlessness.

Introduction: This study examined the clinical profile of cluster headaches in Japan and the potential presence of features peculiar to Japan. Most previous studies of cluster headaches have focused on Caucasian populations.

Methods: Subjects comprised 86 consecutive new cluster headache patients (68 males, 18 females; mean age, 38.4 ± 12.2 years; range, 17-73 years). Mean age at onset was 31.0 years and the ratio of males to females was 3.8:1.

Results: Chronic cluster headache was observed in 3.5% of patients. More than half of patients (68.9%) reported feelings of restlessness during headache episodes and 42.9% reported restless behaviour. Patients with uncoupling of feelings of restlessness and restless behaviour forced themselves to keep still. Similar findings were reported in a Taiwanese study.

Conclusion: Japanese patients in this study showed a relatively low prevalence of chronic cluster headaches, and uncoupling of a sense of restlessness and restless behaviour. These features of cluster headache may be more common in Japanese and Taiwanese patients than in Caucasian patients.