Ravi Raj

Background Knowledge of headache among children (6–11 years) and adolescents (12–17 years) remains relatively sparse. This schools-based, cross-sectional survey in Nepal, in the series of similar studies conducted within the Global Campaign against Headache, was the first in South-East Asia Region. Our aims were to estimate the prevalence among these age groups of each of the headache disorders of public-health importance, and analyse their associations with demographic variables. Methods The study followed the Global Campaign’s standardized protocol. In schools selected to be representative of the country, the child and adolescent versions of the structured Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) questionnaire were completed by pupils in class under supervision. Headache diagnoses followed ICHD-3, with the exception of undifferentiated headache (UdH), which, initially, we defined conventionally as mild headache lasting < 1 h, then redefined as mild-to-moderate headache lasting < 1 h. The diagnosis of UdH took precedence over diagnoses of migraine or tension type headache (TTH). Enquiry timeframes were 1 year and 4 weeks, with questions about headache yesterday (HY) included to circumvent recall error. Results Of 2,360 potential participants in nine schools, 2,352 completed the survey (1,040 children [44.2%]; 1,312 adolescents [55.8%]; participating proportion 99.7%). Males (54.0%) were slightly over-represented. The observed 1-year prevalence of any headache was 85.4% (males 83.5%; females 87.5%). Age- and gender-adjusted estimates were 82.4% for any headache, 39.9% for migraine, 30.3% for UdH (as redefined), 9.5% for TTH, 0.3% for probable medication-overuse headache (pMOH) and 2.0% for other headache on ≥ 15 days/month (H15+). Gender was not strongly associated with any headache type. UdH, TTH and other H15 + were more common among adolescents. Migraine was strongly and positively associated with altitude; the opposite was true for UdH. HY was reported by 20.7% of the sample (1-day prevalence), and by 24.3% of those with any headache (females [29.6%] more than males [19.5%]). The 24.3% was higher than predicted from headache frequency recalled over the preceding 1 week (17.6%) or 4 weeks (10.3%), indicating that participants, in recall, underestimated frequency. Conclusions This study, complementing our adult study, showed that headache is highly prevalent also among children and adolescents in Nepal. As among adults, migraine was strongly and positively associated with altitude. The finding of less pMOH and other H15 + among these young people suggests opportunity to avert some of the headache-attributed burden among adults.