ACEs are traumatic or highly stressful experiences occurring before age 18: physical, emotional, or sexual abuse, neglect, domestic violence, having a family member with mental illness or in prison, among others. The landmark study showed that their accumulation predicts physical and mental health problems decades later with surprising potency.
Concept origin
Felitti et al. (1998) published the original ACE study with 17,000 participants at Kaiser Permanente, showing the dose-response relationship between number of ACEs and heart disease, cancer, depression, and suicide. Developmental neurobiology explains the mechanism: toxic stress in childhood alters the developing brain architecture.
Therapeutic approach
Knowing one's own ACEs is not a diagnosis: it is information that can contextualize current patterns. Intervention does not erase ACEs but builds protective factors: safe relationships, sense of competence and agency, community connection, and treatment of unintegrated trauma when generating current symptoms.
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