Changes in headache prevalence between pre-school and pre-pubertal ages.

The prevalence rates of headache in first-born children were determined at the ages of 6 and 12 years in over 1000 families. A headache questionnaire was mailed to 1132 families when the children were 6 years old, and to 1126 families when the children were 12 years old. Seven hundred and ninety-eight families responded to both questionnaires. The prevalence of headache before the 6 months preceding the questionnaire ('previous headache') was 19% when the children were 6 years of age and 31% when the children were 12 years of age. The corresponding prevalences of headache during the 6 months immediately proceeding the questionnaire ('present headache') were 16% and 19%. Variation in occurrence of headache was high during follow-up years. Maternal frequent headache (> or = 1/month) was significantly associated with the increase in prevalence of present headache in boys between the ages of 6 and 12 years. Frequent headache in mothers, fathers and siblings, and the occurrence of chronic illness, were also significantly associated with headache in the 12-year-old children.