The ACEs Study

In the early 1990s, a physician named Vincent Felitti who worked for Kaiser Permanente in San Diego asked a patient who had lost a great deal of weight in a weight loss program why they had dropped out.

The answer given stunned Dr. Felitti.

That person and many of the other patients in the program that Dr. Felitti interviewed individually expressed that they believed the weight loss made them feel too vulnerable. Many of those he questioned also disclosed experiencing childhood sexual abuse and that they thought deep inside that the excess weight protected them from attack.

The findings of Dr. Felitti were of interest to Dr. Robert Auda who worked for the centers for disease control (CDC), and together they initiated the CDC-Kaiser Adverse Childhood Experiences Study.

In the years between 1995-1997, a study involving 17,000 participants attempt to measure the number of adverse childhood experiences the subjects had experienced throughout their lives. They wanted to understand the relationship between ACEs and the health and life functioning of people who had experienced events in their childhood which were extremely negative.

The study was the first and largest of its kind centered around examining the impact of traumatic events experienced in childhood and their effect on the health of adults.

The findings of the study brought about groundbreaking insights, first of which is that childhood trauma is much more common than previously thought and the prevalence was not limited by race, creed, or income.

This finding that children of every demographic group experience abuse and neglect, was unconventional, as the prevailing thought that children belonging to low socioeconomic status and racial minorities were more often victims of familial violence than white children.

That thought is understandable once you consider the prejudices of the time and the disproportionate number of families from lower socioeconomic status and racial minorities represented in the child welfare system.

The ACEs Study introduced a new narrative on child abuse; it cuts across all populations regardless of income, religion, race, and education.

Through the ACEs study, researchers learned that almost 30% of participants had experienced physical abuse in childhood, and 15% had experienced emotional neglect. However, the results became breathtaking when another study by Dube et al. was reported in a paper published in 2005.

They found that out of 17,337 adults who participated in their study, 16% (1 in 6) men and 25% (1 in 4) women reported sexual abuse before their 18th birthday.

The researchers also discovered that of the ten distinct categories of abuse, neglect and other household stressors related to those acts, the acts rarely occurred as single events. Among adults in the study who reported sexual abuse, 80% also reported at least one other type of abuse perpetrated against them during their childhoods.

However, the following fact really startled the researchers. The men in the study reported they had been perpetrated against women 6% of the time. Women, long thought to be incapable of committing such criminal acts against children were recast into a new light, that of a possible sexual predator.

The Effects of ACEs on the Health of Adults

 As has already been said in this article, the effects on the health of an adult who lived through an abusive or neglectful childhood are greatly devastating. These effects include changes in both the mental and physical health of the survivors.

The ACEs study reported another finding that has consequences for millions around the world. Of the participants studied, the higher the total number of ACEs they reported, the more negative health consequences they experienced.

This unexpected outcome meant there was a graded dose-response in the relationship between the number of ACEs experienced by an individual and the adverse health and well-being across the person’s lifespan.

All that means is that the more negative experiences a person had in their childhood, the higher the negative health consequences they will experience.

These negative health consequences can readily be understood if you see the ACEs pyramid (pictured above). Starting at the bottom, with the experiences and going up one can see the immediate consequences are in social, emotional, and cognitive abilities. It is challenging to concentrate on social skills and schoolwork when you are busy surviving the unthinkable at home.

Moving up we can see the next phase where, as the child grows, they adopt unhealthy and risky behaviors such as overeating, and experiencing drugs and alcohol to numb their pain.

In the next stage up on the pyramid, the risky behaviors take a toll on the mental stability and physical health of those who lived through childhood trauma.

Finally, the health problems caused by behaviors adopted to deal with childhood ACEs take a toll and the child, now an adult dies young.

There are enormous consequences to ACEs to a child grown into adulthood. The list below is by far not all-inclusive:

  • Alcoholism
  • Chronic Obstructive Pulmonary Disease (COPD)
  • Depression
  • Lowered quality of life due to health problems
  • Ischemic heart disease
  • Illicit drug use
  • Liver disease
  • Poor work performance leading to losing jobs
  • Impaired interpersonal relationships
  • Lack of ability to effectively manage finances
  • An increased risk for intimate partner violence (perpetrator and perpetrated against)
  • Numerous sexual partners leading to sexually transmitted diseases
  • Smoking
  • Suicide attempts or death by suicide
  • Unintended pregnancies
  • Eating disorders
  • The development of Borderline Personality Disorder, Dissociative Identity Disorder, and other serious mental health problems

The Economic Costs to the United States for Adverse Childhood Experiences

Although child abuse is a global phenomenon, it is in the United States where the figures for the economic costs are more readily available.

The total economic amount which results from new cases of fatal and nonfatal child abuse and neglect in the U.S. in 2008 was estimated to be 124 billion dollars. This figure is higher than the cost of all other well-known health problems in the country such as stroke and type 2 diabetes.

It even gets more real when one considers the estimated cost per survivor of nonfatal child abuse and neglect which was also estimated in 2008 to be $210,012 per person.

These costs include:

  • Childhood health care costs
  • Productivity losses
  • Adult medical care costs
  • Child welfare costs
  • Special education costs
  • Adult and child mental health care costs

Upon death, each adult survivor of child abuse has an average lifetime cost of $1,272,900 including all medical expenses and productivity losses.

While these figures are staggering, this is just the cost in one single country.

The Brain Changes Caused by ACEs

This page will discuss some of the essential portions of the brain which are affected by ACEs are the corpus callosum, the prefrontal cortex, and the limbic system. There are more regions affected, but for the sake of length, we will not cover them here.

The corpus callosum is the wiring which connects the two hemispheres of the brain. With this wiring damaged by stress hormones, the brain cannot develop healthy communication within the brain structures. This damage leads to impairment of the child’s coordinating learning, gaining healthy self-control and many other vital areas of their development.

Damage to the prefrontal cortex means the child’s brain is incapable of completing healthy development and leads to impairments in attention, memory, and regulation of their behavior. Damage to this region can also have significant changes in the child’s ability to form their personality.

The limbic system of the child’s brain also is incapable of normally forming when exposed to the hormones released during childhood trauma. This vital region of the brain includes the amygdala and the hippocampus. The amygdala is a structure responsible for the response to—and memory of—fear, while the hippocampus is important for the consolidation and correct filing away of memories with their corresponding emotions.

Both structures will not grow to their full size and are significantly affected in these children when they reach adulthood.

Damage to the amygdala leaves adult survivors of ACEs with a brain that is constantly on high-alert and responding to danger when there is none.

Damage to the hippocampus leaves adult survivors having trouble consolidating new memories and also leaves them with triggers that can send the survivor into debilitating flashbacks.

While the damages done to the brain in childhood are permanent, this does not mean a survivor cannot learn ways to mitigate how the damage affects them as adults. We will discuss treatment in today’s article which can be transformational for adult survivors of ACEs.

The Central Nervous System Changes Caused by ACEs

To prepare our body for the fight/flight/or freeze response, hormones are released when the threat becomes noticed. These substances, neurotransmitters, alert our body to breathe faster and to increase our heartbeat, among other reactions necessary to help us get ready to fight or flee.

Typically, after the danger has passed, our body will return to a baseline where the hormones stop flowing, and we return to a resting state. However, the bodies of children who are in constant danger of being attacked, are never given the chance to return to baseline.

The problem with this picture is that these substances cause harm to the child’s developing brain. This damage results in smaller than normal amygdalae and hippocampi as well as other changes that set up the child for a myriad of problems as they reach adulthood.

There are many responses we may be leaving out here, but we’ll tackle the other brain changes later when we discuss the different mental health issues caused by ACEs.

Evidence that ACEs Have a Direct Link to CPTSD and Other Mental Health Issues

It is common knowledge now that adverse childhood experiences, including all forms of child abuse and neglect, are deeply connected to mental health problems in adults. Yet, there are still some scholars and pharmaceutical companies who would discredit these findings.

Nevertheless, the evidence is growing.


A good example is a paper published in the American Journal of Psychiatry in 2004.

The researchers discovered that 89.5% of the sample had one of the following diagnoses: undifferentiated somatoform disorder, generalized anxiety disorder, dysthymic disorder, simple phobia, obsessive-compulsive disorder, major depression, dissociative disorder not otherwise specified, and borderline personality disorder.

That isn’t all.

Researchers also found that dissociative disorders were present in 47.4% of those researched. Unfortunately, those with dissociative disorders also had experienced childhood emotional and sexual abuse, physical neglect, self-harming behaviors, and suicide attempts.

There have been hundreds of scientific inquiries resulting in published research papers linking ACEs and mental health disorders. Many are available free online to the public.

Obviously, since complex post-traumatic disorder is also a trauma-related disorder like those above, ACEs are the main contributing factor to the formation of CPTSD.