title: Testing the Paleolithic-human-warfare hypothesis of blood-injection phobia in the Baltimore ECA Follow-up Study--towards a more etiologically-based conceptualization for DSM-V.
abstract: OBJECTIVE
  The research agenda for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) has emphasized the need for a more etiologically-based classification system, especially for stress-induced and fear-circuitry disorders. Testable hypotheses based on threats to survival during particular segments of the human era of evolutionary adaptedness (EEA) may be useful in developing a brain-evolution-based classification for the wide spectrum of disorders ranging from disorders which are mostly overconsolidationally such as PTSD, to fear-circuitry disorders which are mostly innate such as specific phobias. The recently presented Paleolithic-human-warfare hypothesis posits that blood-injection phobia can be traced to a "survival (fitness) enhancing" trait, which evolved in some females of reproductive-age during the millennia of intergroup warfare in the Paleolithic EEA. The study presented here tests the key a priori prediction of this hypothesis-that current blood-injection phobia will have higher prevalence in reproductive-age women than in post-menopausal women.
  
  
  METHODS
  The Diagnostic Interview Schedule (version III-R), which included a section on blood and injection phobia, was administered to 1920 subjects in the Baltimore ECA Follow-up Study.
  
  
  RESULTS
  Data on BII phobia was available on 1724 subjects (1078 women and 646 males). The prevalence of current blood-injection phobia was 3.3% in women aged 27-49 and 1.1% in women over age 50 (OR 3.05, 95% CI 1.20-7.73). [The corresponding figures for males were 0.8% and 0.7% (OR 1.19, 95% CI 0.20-7.14)].
  
  
  CONCLUSIONS
  This epidemiological study provides one source of support for the Paleolithic-human-warfare (Paleolithic-threat) hypothesis regarding the evolutionary (distal) etiology of bloodletting-related phobia, and may contribute to a more brain-evolution-based re-conceptualization and classification of this fear circuitry-related trait for the DSM-V. In addition, the finding reported here may also stimulate new research directions on more proximal mechanisms which can lead to the development of evidence-based psychopharmacological preventive interventions for this common and sometimes disabling fear-circuitry disorder.
authors.affiliation: National Center for Posttraumatic Stress Disorder, Pacific Islands Division Department of Veterans Affairs, Pacific Islands Health Care System, Spark M. Matsunaga Medical Center, Honolulu, HI 96813-2830, United States. H.BRACHA@MED.VA.GOV
authors.forename: H Stefan
authors.initials: HS
authors.lastname: Bracha
authors.forename: O Joseph
authors.initials: OJ
authors.lastname: Bienvenu
authors.forename: William W
authors.initials: WW
authors.lastname: Eaton
mesh_terms: D000328:Adult; D000367:Age Factors; D015142:Baltimore; D005075:Biological Evolution; D001769:Blood; D001815:Bloodletting / Q000523:psychology; D001921:Brain / Q000503:physiopathology; D003430:Cross-Sectional Studies; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005239:Fear / Q000502:physiology; D005260:Female; D006801:Humans; D007267:Injections / Q000523:psychology*; D008297:Male; D008393:Marriage / Q000523:psychology; D008875:Middle Aged; D010698:Phobic Disorders / Q000145:classification / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology; D012098:Reproduction / Q000502:physiology; D012737:Sex Factors; D014505:Urban Population; D014857:Warfare; D014947:Wounds and Injuries / Q000523:psychology