Cluster Headache in Subjects With Substance Use Disorder: A Case Series and a Review of the Literature.

To describe a case series of 7 patients presenting cluster headache (CH) criteria and a substance use disorder, reported to a French Addictovigilance center. Then, to assess clinical, pharmacological, and neurobiological linkages between substance use and CH onset.CH patients are presenting a higher prevalence of comorbidities, among which the use of psychoactive substances, licit or illicit, have been explored by a few authors. Recently, 3 cases of CH in patients seen in the hospital-based addiction care center have been reported to the Toulouse addictovigilance center.Other cases have been identified in the same tertiary hospital after a collaborative investigation done with the departments of neurology and psychiatry and included in the case series. A narrative review was performed to assess the potential of psychoactive substance consumption to induce or facilitate CH.From 2016 to 2018, 6 males and 1 female aged between 26 and 54 years old, presenting CH criteria and a substance use disorder, were included in our case series. Among substances used, there are: (1) daily use of tobacco and alcohol in 5/7 subjects; (2) daily or almost daily use of cocaine in 5/7 subjects; (3) regular use of cannabis before attacks beginning in 4/7 subjects; and (4) opioids, as a substitutive medication or abused, in 5/7 subjects. The intranasal route administration is reported by all the subjects and precedes the beginning of attacks for 5/7 subjects.We have found a CH prevalence of 0.9% in our studied population, while it is estimated at 0.1% in the general population. The coexistence of cluster headache and addiction behaviors reflects possible common neurobiological pathways, which would include the hypothalamus. Research could be conducted on the potential of hypothalamic therapeutic targets.