Objectives.— The study aim was to determinate changes in prevalence and incidence rates of headache among adolescent Finnish twins.
Methods.— Questionnaire data were collected during 1994‐1998 from a nationwide sample of Finnish families of 11‐year‐old twins who were born between 1983 and 1987 (n = 6262) and again at ages of 14 and 17.
Results.— During follow‐up, the prevalence of regular headache (ie, at least once a month = RHA) increased from 59% at age 11 to 65% at age 14 and decreased to 63% at age 17. Among boys the prevalence of RHA increased significantly from 59% at age 11 to 62% at age 14 decreasing to 52% at age 17. Among girls the prevalence rates increased significantly between ages of 11 and 14 from 60% to 68% up to 74% at age 17. The prevalence of weekly headache increased in girls between ages of 11 and 14 from 16% to 25%. Incidence of RHA (at least once a month) decreased from 47% at age 14 to 44% at age 17 in girls and from 44% at age 14 to 30% at age 17 in boys.
Conclusions.— RHA is more common in girls than boys during puberty, while the incidence of RHA declined especially in boys during same age period.