Abstract
BACKGROUND: Migraine is a complex genetic disorder that is brought about by multiple genetic and environmental factors. We aimed to assess whether migraine frequency is associated with genetic susceptibility. METHODS: We investigated in 2829 migraine patients (14% males) whether 'migraine frequency' (measured as the number of migraine days per month) was related to 'genetic load' (measured as the number of parents affected with migraine) using a validated web-based questionnaire. In addition, we investigated associations with age-at-onset, migraine subtype, use of acute headache medication, and comorbid depression. RESULTS: We found an association between the number of migraine days per month and family history of migraine for males ( p = 0.03), but not for females ( p = 0.97). This association was confirmed in a linear regression analysis. Also, a lower age-at-onset ( p < 0.001), having migraine with aura ( p = 0.03), and a high number of medication days ( p = 0.006) were associated with a stronger family history of migraine, whereas lifetime depression ( p = 0.13) was not. DISCUSSION: Migraine frequency, as measured by the number of migraine days per month, seems associated with a genetic predisposition only in males. A stronger family history of migraine was also associated with a lower age-at-onset, a higher number of medication days, and migraine with aura. Our findings suggest that specific clinical features of migraine seem more determined by genetic factors.