title: [Migraine and evolutionary theory: paths for a clinical approach].
abstract: BACKGROUND
  Migraine is a very common disorder with a raising incidence. The theory of evolution allow us to explain the emergence of the disorder, due to the advantages that the overreactivity to stimulus provided to ancestral groups of Homo sapiens, and a greater presence of the disorder in modern societies, based in the interactions with external factors. Herein we analyze these points.
  
  
  METHODS
  Design of organisms and their responses to environmental factors emerge to improve survival. Thus pain and headache can be contemplated as homeostatic and adaptative responses. Below 10% of the population has no experience with headache and the migrainous phenotype is quite frequent in secondary headaches and in syndromic forms of migraine. These features can be understood under the next undergrounds: specific neurophysiological data (lack of habituation, sensibilization and low preactivation), genetic features (polygenic disorder with the implication of many gens with a low penetrance, that interact with the environment and are shared with comorbid disorders such as depression and anxiety); and environmental interactions in modern societies (increase in the number of estrogenic cycles and particularly overexposition to stress).
  
  
  CONCLUSIONS
  A feature that was an evolutionary advantage has been transformed in a highly prevalent and disabling disorder in modern societies. It is the result of the interaction with internal (estrogenic cycles) and external (stress) stimuli. As a consequence, it becomes a mismatch disorder. The effects appear in childhood through epigenetics. Therefore, therapeutic interventions would yield greater benefits if whole populations were included in educative interventions incorporating these aspects.
authors.affiliation: Hospital de Basurto, 48013 Bilbao, Espana.
authors.forename: L C
authors.initials: LC
authors.lastname: Alvaro-Gonzalez
mesh_terms: D001008:Anxiety Disorders; D015897:Comorbidity; D003863:Depression; D006261:Headache / Q000503:physiopathology*; D006801:Humans; D008881:Migraine Disorders / Q000503:physiopathology*