Cluster headache beyond the pain phase: A prospective study of 500 attacks.

Objective: To describe the nature, prevalence, and duration of symptoms in the preictal, ictal, and postictal phases of cluster headache (CH) attacks.

Methods: Fifty-seven patients with episodic or chronic CH participated in this prospective, observational study. In a questionnaire concerning 33 CH and migraine-related symptoms, patients reported the clinical features of up to 10 CH attacks/patient. The questionnaire was divided into 3 sections: a preictal phase, ictal phase, and postictal phase. For each phase, patients documented whether the given symptom was present, and if possible estimated the duration of the symptom.

Results: In total, 500 CH attack descriptions were obtained. In the preictal phase, general symptoms (most frequently concentration difficulties, restlessness, and mood changes) occurred 20 minutes prior to 46.0% of attacks. Local painful and autonomic symptoms were observed 10 minutes prior to 54.6% and 35% of attacks, respectively. Postictally, pain and autonomic symptoms resolved over 20 minutes, leaving patients with fatigue (36.2%), decreased energy (39.0%), and concentration difficulties (27.6%), lasting a median of 60 minutes.

Conclusions: Preictal and postictal symptoms are very frequent in CH, demonstrating that CH attacks are not composed of a pain phase alone. Since the origin of CH attacks is unresolved, studies of preictal and postictal symptoms could contribute to the understanding of CH pathophysiology and, potentially, early, abortive treatment strategies.