The prevalence and characteristics of migraine in twins from the general population.

We examined whether prevalence, age at onset, and cessation of migraine without aura and migraine with aura are different among twins and singletons. The study population was recruited from the population-based New Danish Twin Register and comprised 2026 monozygotic and 3334 same-sex dizygotic twins born during 1953 to 1960. A simple questionnaire was used to screen for migraine. Twin pairs with at least one twin with possible migraine were interviewed by telephone by two physicians. A total of 1136 twin pairs were included in the telephone interviews. The criteria of the International Headache Society were used for diagnosis. The questionnaire response rate was 87%, and the telephone interview participation rate was 90%. Of the 715 migraineurs, 498 had migraine without aura, 264 had migraine with aura, and 47 had both migraine with and without aura. The lifetime prevalence, age at onset, and cessation of migraine with and without aura did not differ in monozygotic and dizygotic twins. Males and females had a lifetime prevalence of migraine without aura of 7% and 19%, respectively. The female preponderance of migraine without aura was first apparent after aged 14 years; this may be related to an influence of female hormones. The lifetime prevalence of migraine with aura was 7% in males and 8% in females. The observed and expected number of those with both migraine with and without aura was not significantly different, suggesting that migraine without aura and migraine with aura are distinct types of migraine. Males with migraine without aura had a significantly lower mean age at onset than females with migraine without aura (16.5 years versus 21.5 years), while males and females with migraine with aura had similar ages at onset (20.8 years versus 21.8 years). About 20% of the twins had ceased having attacks of migraine with or without aura. More males than females with onset of migraine without aura before aged 15 years had ceased having attacks. The prevalence of migraine without aura and migraine with aura in twins was similar to the prevalence in the general population. Being a twin did not affect age at onset or cessation of migraine. Previous observations on differences of migraine without aura and migraine with aura regarding gender was confirmed.