The prevalence and impact of headache in Brazil.

Abstract

In Brazil, several epidemiological studies on headache have been produced, most with an emphasis on prevalence and the association of primary headaches with some sociodemographic characteristics of the population. Data on the burden of headache, however, are scarce. The aim of this paper is to review all Brazilian population-based studies on headache, as well as to analyze the Migraine Disability Assessment Score (MIDAS) data collected with the PhD thesis of the senior author (LPQ). A literature review was performed using the keywords ("headache" or "migraine") and ("epidemiology" or "prevalence") and (Brazil). Another part of this paper will look at unpublished data on disability (MIDAS), collected with the prevalence data of the Brazilian nationwide epidemiological study of headache. There are 6 published epidemiological studies of headache in Brazil. The mean 1-year prevalence of headache in Brazil is 70.6%, of migraine 15.8%, of tension-type headache (TTH) 29.5%, and of chronic daily headache (CDH) 6.1%. Disability is significantly higher: in females compared to males; in patients with migraine and CDH compared to patients with TTH; and in those with headaches ≥15 days per month rather than those with episodic headaches. There was also a positive relationship between pain intensity and severity of disability. Patients with higher disability used more both abortive and prophylactic medication. The mean prevalence of headache in Brazil, and some of its subtypes, is similar to the rates described in other countries of the world. Disability is higher in females, in patients with migraine, in individuals with headaches ≥15 days per month, and in those with severe head pain.