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Chronic daily headache in adolescents

Objective: To assess the long-term outcome of a community-based adolescent cohort with chronic daily headache (CDH). Methods: A field sample of 122 adolescents aged 12–14 years with CDH was established in 2000 (baseline) with short-term follow-up studies in 2001 and 2002. In 2008, the cohort was re-interviewed by physicians via telephone to determine the headache profile for the past year, including Migraine Disability Assessment (MIDAS), a headache disability questionnaire. Presence of CDH was defined as ≥15 headache days/month, average ≥4 hours/day for >3 months. Outcome measures included headache frequency, MIDAS score, and presence of CDH in 2008. Results: A total of 103 subjects (26 male/77 female, mean age 21.6 ± 0.9 years) completed the study (response rate 84.4%). The average monthly headache frequency was 4.7 ± 6.0 (0–30) days. Twenty-eight (27.2%) subjects had moderate or severe headache disability (MIDAS ≥11). Twelve (12%) subjects met CDH criteria, with chronic migraine (n = 10, 83%) as the most common subtype. Two (2%) subjects overused medications. From 2000 to 2008, the frequencies of migraine diagnoses were fairly consistent in this cohort. Presence of migraine at baseline predicted poorer outcome of all 3 measures. Additionally, CDH onset <13 years old, duration ≥2 years, and medication overuse predicted either higher headache frequencies or presence of CDH in 2008. Conclusions: This long-term follow-up study revealed a marked decline in the frequency of chronic daily headache (CDH). However, one fourth of patients still had significant headache disability. Migraine history was a major factor in evolution of CDH into young adulthood. Early onset and longer duration of CDH implied a protracted disease course.