Objective.—To investigate the familial occurrence of cluster headache in a series of French patients fulfilling the International Headache Society diagnosis criteria.
Methods.—One hundred eighty-six index patients and 624 first-degree relatives were surveyed.
Results.—A positive family history of cluster headache was found in 20 index patients (10.75%) with 22 affected first-degree relatives (3.4%). In multiplex families 6 of the 68 second-degree relatives that were contacted had cluster headache.
Conclusion.—No precise mode of inheritance could be drawn from the observed repartition of cases within multiplex families.