Adverse Childhood Experiences (ACE) Study Summary

Adverse Childhood Experiences (ACEs) refer to stressful or traumatic events that children face before reaching 18.

These include various forms of abuse (physical, emotional, sexual), neglect (emotional, physical), and household challenges such as witnessing domestic violence, living with substance abusers, having an incarcerated relative, or experiencing family separation.

Studies have shown that individuals with a high number of ACEs are at an increased risk for negative outcomes in adulthood, including chronic diseases, mental illness, substance misuse, and reduced life potential. The more ACEs one has, the greater the risk for these outcomes.

Felitti, V. J., Anda, R. F., Nordenberg, D., Williamson, D. F., Spitz, A. M., Edwards, V., & Marks, J. S. (1998). Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The Adverse Childhood Experiences (ACE) Study. American Journal of Preventive Medicine, 14(4), 245-258.

Key Points

• Adverse childhood experiences like abuse, violence, and family dysfunction are common and have strong, cumulative effects on adult health risk behaviors and diseases.
• Over half of the study participants reported at least one adverse childhood experience. As the number of adverse experiences increased, so did the risk for smoking, alcoholism, drug abuse, depression, suicide attempts, multiple sexual partners, sexually transmitted diseases, heart disease, cancer, chronic lung disease, skeletal fractures, and liver disease.
• People with 4 or more adverse childhood experiences had up to 12 times higher likelihood of suicide attempts, 7 times higher chance of alcoholism, and 10 times higher risk of injected drug use compared to people with no adverse experiences.
• Adverse childhood experiences tend to be interrelated rather than occurring in isolation. People exposed to one category had a 65-93% chance of exposure to other categories as well.
• The research had some limitations such as reliance on retrospective self-report and the study population being mostly white, middle-aged, and middle-class. However, it highlights the profound, long-term impact of childhood adversity on adult health.

Rationale

Child abuse, neglect, and other adverse childhood experiences have been associated with poorer health outcomes in adulthood (Springs & Friedrich, 1992; Felitti, 1991, 1993).

However, prior studies focused on single forms of adversity and did not assess the cumulative impact of multiple experiences (Briere & Runtz, 1988; Moeller et al., 1993).

This study aimed to examine the relationship between the breadth of exposure to abuse, violence, and family dysfunction in childhood and health risk behaviors, health status, and diseases in adulthood. Understanding these associations can inform more effective prevention and treatment strategies.

Method

This retrospective cohort study surveyed 13,494 adult health maintenance organization (HMO) members who had a standardized medical evaluation at a clinic.

The mailed survey asked about adverse childhood experiences like psychological, physical, or sexual abuse; violence against mother; or living with household members who were substance abusers, mentally ill, suicidal, or imprisoned.

The number of exposure categories (0-7) was compared to the presence of risk factors for leading causes of death and disease conditions using logistic regression models.

Sample:

After exclusions, the final sample was 8,056 people aged 19-92 years, predominantly white (79%) and college-educated (43%). 53% were women.

Statistical Analysis

Logistic regression analyzed the relationship between the number of childhood exposures and health outcomes, adjusting for age, sex, race, and education. Dose-response was tested by entering exposures as an ordinal variable.

Results

• 52% of participants had at least one adverse childhood experience.
• As exposures increased from 0 to 4+, smoking prevalence rose from 7% to 17%, severe obesity from 5% to 12%, depressed mood from 14% to 51%, and suicide attempts from 1% to 18%.
• The odds of alcoholism, drug abuse, sexual partners, and STDs also increased with more exposures.
• Heart disease, cancer, lung disease, skeletal fractures, and fair/poor health showed significant dose-response relationships.

Implications

• This study reveals the surprisingly common and powerful long-term effects of adverse childhood experiences like abuse, domestic violence, and household dysfunction.
• The cumulative impact of adverse childhood experiences explains the adoption of unhealthy coping behaviors like smoking, overeating, alcoholism, drug use, and risky sex. It also elucidates the link to stress-related diseases later in life.

The findings underscore the critical need for increased attention to primary, secondary, and tertiary prevention strategies.

• Primary Prevention: Focus on preventing ACEs from occurring in the first place, requiring societal changes to improve family and household environments. Initiatives like early home visitation programmes for new parents show promise in this regard.
• Secondary Prevention: Aims to prevent the adoption of health-risk behaviours as responses to adverse childhood experiences. This involves increased recognition of ACEs and effective understanding of the behavioural coping mechanisms involved. Comprehensive strategies are needed to identify and intervene with at-risk children and families, requiring better communication and training across medical and public health disciplines.
• Tertiary Prevention: Involves helping adults whose health problems are a long-term consequence of ACEs. This requires physicians and healthcare practitioners to acknowledge and inquire about these sensitive childhood experiences, despite the time delay and emotional nature of the topics. Understanding these links can lead to more effective health promotion and disease prevention programmes for adults.

Future Research

• Understanding ACEs is crucial, as early interventions can prevent future health and social problems, promoting resilience and providing support mechanisms to counteract these early life stressors.

Strengths & Limitations

The study had many methodological strengths, including:

• Large sample size with high response rate (70.5%)
• Assessed range of childhood exposures, not just single types of adversity
• Used logistic regression to control demographic factors
• Found relationships robust to missing data in sensitivity analysis

However, this study was limited in a few ways:

• Retrospective self-report prone to recall bias
• Mostly white, educated, middle-class, so may not generalize
• Can’t determine causality due to study design

Conclusion

This study reveals powerful relationships between the breadth of exposure to childhood adversity and health risk behaviors and diseases in adulthood.

It underscores the profound, long-term impact of adverse developmental experiences.

More research is needed, but these findings suggest that prevention and intervention around childhood adversity could improve public health.

Healthcare providers should be alert for patients whose health problems may have developmental origins.

Further progress relies on compassionately understanding how high-risk health behaviors may represent coping responses in the face of trauma and cumulative stress.

References

Primary Paper

Felitti, V. J., Anda, R. F., Nordenberg, D., Williamson, D. F., Spitz, A. M., Edwards, V., & Marks, J. S. (1998). Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The Adverse Childhood Experiences (ACE) Study. American Journal of Preventive Medicine, 14(4), 245-258.

Other References

Briere, J., & Runtz, M. (1988). Multivariate correlates of childhood psychological and physical maltreatment among university women. Child Abuse & Neglect, 12(3), 331-341.

Felitti, V. J. (1991). Long-term medical consequences of incest, rape, and molestation. Southern Medical Journal, 84(3), 328-331.

Felitti, V. J. (1993). Childhood sexual abuse, depression, and family dysfunction in adult obese patients: a case control study. Southern Medical Journal, 86(7), 732-736.

Moeller, T. P., Bachman, G. A., & Moeller, J. R. (1993). The combined effects of physical, sexual, and emotional abuse during childhood: Long-term health consequences for women. Child Abuse & Neglect, 17(5), 623-640.

Springs, F., & Friedrich, W. N. (1992). Health risk behaviors and medical sequelae of childhood sexual abuse. Mayo Clinic Proceedings, 67(6), 527-532.

Further Reading

• Chapman, D. P., Whitfield, C. L., Felitti, V. J., Dube, S. R., Edwards, V. J., & Anda, R. F. (2004). Adverse childhood experiences and the risk of depressive disorders in adulthood. Journal of affective disorders, 82(2), 217-225.
• Dube, S. R., Felitti, V. J., Dong, M., Chapman, D. P., Giles, W. H., & Anda, R. F. (2003). Childhood abuse, neglect, and household dysfunction and the risk of illicit drug use: the adverse childhood experiences study. Pediatrics, 111(3), 564-572.
• Felitti, V. J. (2009). Adverse childhood experiences and adult health. Academic pediatrics, 9(3), 131-132.
• Hamai, T. A., & Felitti, V. J. (2022). Adverse childhood experiences: Past, present, and future. Handbook of interpersonal violence and abuse across the lifespan: a project of the national partnership to end interpersonal violence across the lifespan (NPEIV), 97-120.

Learning Check

Quiz: Short Answer Questions

Answer each question in 2-3 sentences.

1. What was the primary objective of the ACE Study as described in this research article?
2. List the seven categories of adverse childhood experiences (ACEs) that were investigated in the study.
3. Describe the key finding regarding the relationship between the number of ACE categories and adult health risks.
4. How did the study define “severe obesity” and “physical inactivity”?
5. What was the response rate for the mailed questionnaire in the ACE Study, and what does this suggest about the study’s generalisability?
6. Explain why the researchers believe their estimates of the long-term relationship between ACEs and adult health might be conservative.
7. According to the authors, how might health risk behaviours like smoking or drug abuse function as “coping devices” for individuals with a history of ACEs?
8. What were the most and least prevalent categories of childhood exposure reported by the respondents?
9. The study found a “dose-response relationship” for many health problems. What does this term mean in the context of this study?
10. What recommendations do the authors make for primary, secondary, and tertiary prevention strategies related to ACEs?

Answer Key for Quiz

1. The primary objective of the ACE Study was to describe the long-term relationship between exposure to childhood abuse and household dysfunction and important medical and public health problems, specifically adult health risk behaviours, health status, and disease states. It aimed to assess the cumulative influence of multiple categories of adverse childhood experiences.
2. The seven categories of adverse childhood experiences (ACEs) investigated were: psychological abuse, physical abuse, sexual abuse, substance abuse in the household, mental illness in the household, violence against mother/stepmother, and criminal behaviour in the household. These covered both direct abuse and household dysfunction.
3. The study found a strong, graded (dose-response) relationship between the number of categories of childhood exposure and each of the adult health risk behaviours and diseases studied. As the number of ACE categories increased, there was a proportionally increased health risk.
4. “Severe obesity” was defined as a body mass index (BMI) of 35 kg/meter² or greater, based on measured height and weight. “Physical inactivity” was defined as no participation in recreational physical activity in the past month.
5. The response rate for the mailed questionnaire was 70.5% (9,508 out of 13,494 eligible adults). This high response rate, combined with similar demographics between respondents and non-respondents (except for age and race), suggests that the study’s findings are broadly generalisable to the adult population of the HMO.
6. The researchers believe their estimates might be conservative because data on adverse childhood experiences are self-reported and retrospective, potentially leading to underreporting. Additionally, premature mortality among those with multiple ACEs could mean the study’s older participants had fewer reported ACEs than they truly experienced.
7. The authors suggest that health risk behaviours like smoking, alcohol, or drug abuse may be consciously or unconsciously adopted as immediate pharmacological or psychological coping devices. These behaviours could provide temporary relief from the anxiety, anger, and depression stemming from childhood stress.
8. The most prevalent category of childhood exposure reported was substance abuse in the household (25.6%). The least prevalent exposure category was criminal behaviour in the household (3.4%).
9. In the context of this study, a “dose-response relationship” means that as the “dose” (the number of categories of adverse childhood experiences) increases, the “response” (the prevalence and risk of adult health problems) also consistently increases in a measurable way. It implies a direct correlation between the magnitude of childhood adversity and later health outcomes.
10. For primary prevention, they recommend societal changes to improve family environments and early home visitation programmes for new parents. For secondary prevention, increased recognition of ACEs and understanding of coping behaviours are crucial. For tertiary care, they suggest improved understanding and management of adult health problems linked to childhood experiences.

Essay Format Questions

1. Discuss the methodology of the ACE Study, including its strengths and limitations. How do the researchers address potential biases, and what further considerations might influence the interpretation of their findings?
2. Analyse the concept of “dose-response relationship” as applied in the ACE Study. Provide specific examples from the results to illustrate how this graded relationship manifests across different health risk factors and disease conditions in adulthood.
3. The authors propose that certain health risk behaviours serve as “coping devices” for individuals who experienced adverse childhood experiences. Elaborate on this hypothesis, explaining the psychological and biobehavioural mechanisms suggested, and discuss its implications for public health interventions.
4. Evaluate the study’s implications for public health and medical practice. What specific recommendations for prevention (primary, secondary, and tertiary) are made, and what challenges might arise in implementing these recommendations?
5. Compare and contrast the impact of different categories of adverse childhood experiences. Based on the study’s findings, how interconnected are these experiences, and what does this suggest about the comprehensive nature required for interventions?

Glossary of Key Terms

• Adverse Childhood Experiences (ACEs): A set of traumatic experiences that can occur in childhood, including abuse (psychological, physical, sexual) and household dysfunction (e.g., substance abuse, mental illness, violence against mother, criminal behaviour in the household).
• Dose-Response Relationship: A graded relationship where the effect (response) of a factor increases proportionally with the intensity or quantity (dose) of exposure to that factor. In the ACE Study, it refers to the increasing health risks with a higher number of ACE categories.
• Household Dysfunction: Adverse experiences occurring within the family environment, distinct from direct abuse, such as living with substance abusers, mentally ill or suicidal individuals, or those who have been imprisoned, or exposure to violence against a parent.
• Ischemic Heart Disease: A condition where the heart muscle receives insufficient blood supply, often due to narrowed arteries.
• Logistic Regression: A statistical method used to predict the probability of a binary outcome (e.g., presence or absence of a disease) based on one or more predictor variables, often used to adjust for confounding factors.
• Odds Ratio (OR): A measure of association between an exposure and an outcome. An OR of 2.0 means that the exposed group has twice the odds of the outcome compared to the unexposed group.
• P-value (P < .001, P < .05): In statistics, the probability of obtaining test results at least as extreme as the observed results, assuming that the null hypothesis is correct. A small p-value (e.g., <.001 or <.05) suggests that the observed results are statistically significant and unlikely to have occurred by chance.
• Prevalence: The proportion of a particular population found to have a condition (or characteristic) at a specific time.
• Primary Care Setting: Medical care provided by a physician or other healthcare professional who acts as the first point of consultation for all patients.
• Retrospective Study: A study that looks back in time to examine exposures or risk factors in relation to an outcome that has already occurred.
• Self-Rated Health: An individual’s subjective assessment of their overall health, often measured on a scale from excellent to poor, and known to be a strong predictor of mortality.
• Sensitivity Analysis: A technique used to determine how different values of an independent variable affect a particular dependent variable under a given set of assumptions. In this study, it checked if excluding participants with incomplete data influenced the results.