LOS ANGELES — Marijuana use was more common among 139 French patients with cluster headaches than among the general population, but their reports of the effect of the drug on headaches were variable and uncertain.
Dr. Elizabeth Leroux and her associates surveyed 115 male and 24 female patients presenting with cluster headaches at the Emergency Headache Center in Paris and the Headache Clinic in Marseille, France.
On questionnaires, 45% of the patients described themselves as cannabis (marijuana) users, which the investigators defined as any repeated use of cannabis except for isolated trials during their teenage years.
In the previous 6 months, a total of 32% of the patients had used cannabis.
Those rates were significantly higher than the rates of use among the general French population, Dr. Leroux of Lariboisière Hospital, Paris, reported in a poster presentation at the meeting.
Previous data from other investigators suggest that 12% of men and 5% of women in France had used cannabis in 2006.
Clinicians should address substance use when caring for patients with cluster headaches, in order to prevent complications from drug use and potential interactions with prescription medications, Dr. Leroux advised.
The 63 cannabis users in the current study were more likely to be young men and tobacco smokers than were the 73 headache patients who didn't use cannabis. (Three other patients who had once used cannabis to try to treat a cluster headache attack did not describe themselves as users and were excluded from some analyses.)
The mean age was 36 years for cannabis users and 45 years for nonusers. Males made up 59 of the 63 cannabis users and 54 of the 73 nonusers. Among the cannabis users, a total of 58 (92%) reported that they smoke tobacco, compared with 43 (60%) of the nonusers.
The effects of cannabis on cluster headaches were no clearer than a smoke-filled room, with 27% of patients saying that they think cannabis could provoke a cluster headache attack, 59% saying they do not think so, and no response from the rest.
Four patients (3% of the cohort) said they believe that cannabis could either provoke or abort cluster headache attacks.
Among the 63 cannabis users, 27 (43%) said they avoid cannabis during an attack of cluster headaches, 24 patients (38%) said they do not avoid cannabis during attack periods, and 12 patients (19%) didn't answer the question.
A total of 27 patients had tried cannabis specifically to treat their cluster headache attacks, and 20 of them had tried this more than twice.
Their reports of the effect of cannabis on headaches were variable as well.
One patient (3%) said that cannabis was “very efficient” in treating cluster headache, 6 patients (22%) said cannabis gave them more than 50% relief from headache pain, 6 patients (22%) said cannabis was not helpful or made the headache worse, and 14 patients (53%) said the drug's effects on cluster headache were “variable or uncertain.”
The study provides some of the first data on cannabis use in this population.
Cannabis contains the compound delta-9-tetrahydrocannabinol, an agonist of cannabinoid receptors, which have antinociceptive properties and effects on cerebral arteries, the investigators noted.
Disclosures: The investigators reported having no pertinent conflicts of interest.