Cluster Headache: Epidemiology, Pathophysiology, Clinical Features, and Diagnosis

Abstract

Cluster headache is a primary headache disorder and is the most prevalent of the trigeminal autonomic cephalalgias. Cluster headache significantly impacts those affected, necessitating early diagnosis and management. Despite unique clinical features, such as patients experiencing attacks in a circannual pattern and often with a circadian rhythm within bouts, cluster headache patients often are misdiagnosed, mismanaged and have a delay in diagnosis. Preclinical, neuroimaging and clinical studies have advanced our understanding of cluster headache pathophysiology. The trigeminovascular system, the trigeminal autonomic reflex, and the hypothalamus are all involved in the pathophysiology of cluster headache. As our understanding of the pathophysiology of cluster headaches has evolved, new therapeutic options, such as calcitonin gene-related peptide monoclonal antibodies, non-invasive vagal nerve stimulation and sphenopalatine ganglion stimulation, have proved to have efficacy in the treatment of cluster headache. Herein, we aim to review developments to aid readers in their understanding of this debilitating disorder.