Long-term trends in the incidence of headache in Finnish schoolchildren

OBJECTIVE. To study changes over time in the incidence of migraine and frequent headache. METHODS. A population-based study on migraine and other headaches in Finnish children starting school at age 7 years in the city of Turku was conducted in 1974, 1992, and 2002. The study design used in each study was virtually identical. The study population included 1927 children in 1974, 1436 children in 1992, and 1066 children in 2002. The corresponding response rates were 90%, 96%, and 81%. RESULTS. An increasing trend in the incidence of migraine was found from 1974 to 2002 in both boys and girls. The incidence rates of migraine with aura increased from 5.2 per 1000 person-years in 1974 to 41.3 per 1000 person-years in 2002. The increase in the rates of migraine without aura was from 14.5 per 1000 person-years in 1974 to 91.9 in 2002. Similarly, a significant increase over time was seen in the incidence of frequent headache from 1974 to 2002 in both boys and girls. CONCLUSIONS. The incidence of childhood migraine and frequent headache has substantially increased over the last 30 years. The increased incidence is alarming and reflects untoward changes in children's lifestyles. Additional studies are needed on causal associations with life changes.