Primary headache disorders among the adult population of Mongolia: prevalences and associations from a population-based survey

Background In the ongoing Global Campaign endeavour to improve knowledge and awareness of headache prevalence worldwide, Mongolia is a country of interest. It sits between Russia and China, in which prevalence is, respectively, much higher and much lower than the estimated global mean. We conducted a population-based study in Mongolia both to add to knowledge and to inform local health policy. Methods Using standardized methodology with cluster random sampling, we selected Mongolian adults (aged 18–65 years) from five regions reflecting the country’s diversities. They were interviewed by trained researchers, cold-calling at their homes, using the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) structured questionnaire following pilot-testing. ICHD-3 beta diagnostic criteria were applied. Results N = 2043 (mean age 38.0 [±13.4] years, 40% urban-dwelling and 60% rural), with a non-participation proportion of 1.7%. Males were somewhat underrepresented, for which corrections were made. The crude 1-year prevalence of any headache was 66.1% (95% CI: 64.0–68.2%), with a strong female preponderance (OR: 2.2; p < 0.0001). Age- and gender-adjusted prevalences were: migraine 23.1% (for females, OR = 2.2; p < 0.0001); tension-type headache (TTH) 29.1% (no gender difference); probable medication-overuse headache (pMOH) 5.7% (trending towards higher in females); other headache on ≥15 days/month 5.0% (for females, OR = 2.2; p = 0.0008). Unclassified cases were only 35 (1.7%). Any headache yesterday was reported by 410 (20.1%; for females, OR = 2.4; p < 0.0001). Only pMOH showed a strong association with age, peaking in middle years with a 5-fold increase in prevalence. Migraine showed a consistent association with educational level, while pMOH showed the reverse, and was also more common among other groups than among participants who were single (never married). Migraine was less common among rural participants than urban (OR: 0.80; p = 0.0326), while pMOH again showed the reverse (OR: 2.4; p < 0.0001). Finally, pMOH (but not migraine or TTH) was significantly associated with obesity (OR: 1.8; p = 0.0214). Conclusion Headache disorders are common in Mongolia, with, most notably, a very high prevalence of headache on ≥15 days/month corroborated by the high prevalence of headache yesterday. The picture is very like that in Russia, and dissimilar to China. There are messages for national health policy.

Headache yesterday in China: A new approach to estimating the burden of headache, applied in a general-population survey in China

Background In order to minimize recall bias in burden estimation, questions about headache yesterday were included in a population-based survey initiated by Lifting The Burden: The Global Campaign against Headache. Methods Throughout China, nonrelated respondents aged 18–65 years were randomly sampled from the general population by a door-to-door survey. A validated structured questionnaire included inquiry into occurrence and burden of headache on the preceding day (“headache yesterday”). Results The participation rate was 94.1%. Of 5041 participants, 286 (5.7%) (male 3.6%, female 7.9%) reported headache yesterday. Age-weighted prevalence of headache yesterday was 4.8% (male 3.0%, female 6.6%). Headache yesterday lasted all day in 36.8%, <1 hour in 14.3% and for a mean of 3.7 ± 3.3 hours in 48.9%. Headache yesterday was moderate to severe in 79.9%; disability such that they could do less than half of what they had expected was reported by 19.9% and such that they could do nothing by a further 7.5% (total 27.4%). Almost three-quarters (71.5%) with headache yesterday took medication to treat it. Conclusions Of the adult Chinese population, 1.8% have headache at any one time that is of moderate to severe intensity in 1.4%, and 1.3% lose the equivalent of a whole day to headache-attributed disability every day. In China this means 12.3 million people.