Objective.-To investigate the incidence of medically recognized migraine in
Olmsted County, Minnesota, during the years 1989 to 1990.
Methods.-We used the records-linkage system of the Rochester Epidemiology P
roject to identify all subjects who sought medical attention for their head
ache and had their initial visit for migraine within the study period. Inci
dent cases were classified using specified criteria.
Results.-From 9837 records screened, we found 713 incident cases. The avera
ge annual incidence rate (new cases per 100 000 person-years) was 343.0 in
both sexes combined, 481.6 in women, and 194.4 in men. In women, incidence
rates were low at the extremes of age and higher among those aged between 1
0 and 49 years, with a striking peak at the age of 20 to 29 years, Migraine
without aura was the most common type of migraine in women, Men had a more
constant risk of migraine throughout life with a lesser peak at the age of
10 to 19 years, and they were equally affected by all types of migraine. W
omen had consistently higher incidence rates than men at all ages, and ther
e were strikingly higher incidence rates of migraine without aura in women
than in men.
Conclusions.-Although our incidence rates were restricted to medically reco
gnized cases of migraine, we confirmed previously reported epidemiological
patterns.