Nadine Burke-Harris, who treated children with ADHD, is among a growing number of health-care practitioners who maintain there is a link between adult illnesses and childhood trauma. Picture: SUPPLIED
Nadine Burke-Harris, who treated children with ADHD, is among a growing number of health-care practitioners who maintain there is a link between adult illnesses and childhood trauma. Picture: SUPPLIED

US-based paediatrician Nadine Burke-Harris had a glut of attention deficit hyperactivity disorder (ADHD) cases at the clinic where she worked in Bayview, a poor area in San Francisco. She felt in her bones that these cases didn’t come out of the blue, and were directly linked to high levels of toxic stress in the community.

Toxic stress, experienced through consistent exposure to violence, abuse and the consequences of poverty and inequality, has a lasting effect on the brain, notably in the way it perceives and processes stress. Burke-Harris asked herself whether the cause of the children’s ADHD symptoms was not a mental disorder, but a biological process that worked on the brain to disrupt normal functioning.  

“Twenty years of medical research has shown that childhood adversity literally gets under our skin, changing people in ways that can endure in their bodies for decades. It can tip a child’s development trajectory and affect physiology. It can trigger chronic inflammation and hormonal changes that can last a lifetime. It can alter the way DNA is read and how cells replicate, and it can dramatically increase the risk for heart disease, stroke, cancer, diabetes — even Alzheimer’s,” she writes in her book The Deepest Well: Healing the Long-Term effects of Childhood Adversity.

Using the Adverse Childhood Experiences (ACE) test, Burke-Harris and her colleagues found a way to screen for toxic stress, and to quantify and interpret data. The test, which was formulated by Vincent Felitti, the head of Kaiser Permanente’s department of preventative medicine in San Diego, asks 10 questions and for every yes, one point is given. Higher scores are often correlated with poorer health.

Felitti formulated the test to delve deeper into his anecdotal findings that obesity in adults was linked to experiences of childhood sexual abuse. His questionnaire was based on information provided by 17,377 participants and is seen as substantial enough to be applied across numerous settings. Questions include topics such as physical and emotional abuse, whether the individual’s parents were separated or divorced, and whether a member of the household went to prison (see below for full questionnaire).

Community impact

Burke-Harris expanded the original questionnaire to include questions about community violence, homelessness, discrimination, foster care, bullying, repeated medical procedures or life-threatening illness, death of a caregiver, loss of a caregiver to deportation or migration, and, for youth, verbal or physical violence from a romantic partner and youth incarceration.

Zimbabwean researcher Mercy Manyema of the DST-NRF Centre of Excellence in Human Development, based at Wits School of Public Health, concurs with Burke-Harris that adversity affects biological processes and is a plausible cause of illnesses that involve the cardiovascular, immune and endocrine systems.

“Higher levels of the stress hormone corticosterone affects the function of other hormones and body systems,” said Manyema.

Manyema’s research, conducted with Linda Richter and Shane Norris in 2018, showed that a high proportion of the young adults studied were exposed to adverse childhood experiences.

Ninety percent said yes to one of the questions and 15% said yes to four questions. A score of four or more is associated with an increased risk of suicide attempts, lifetime depressive disorders and poor mental health. Alcohol misuse was also higher. Those who experienced six or more ACEs had nearly eight times greater odds of mental illness in adulthood. The average number of ACE scores in the SA study was three.

The study, which expands the original ACE questions from 10 to 13 to include chronic illness, unemployment and death of a caretaker (in light of SA’s HIV/Aids prevalence and high income inequality and poverty), revealed that the cohort have higher ACE scores than those studied in England and Wales (46% and 47% suffered at least one ACE and 8.3% and 14% experienced four or more) and Brazil (85% experienced at least one).

Manyema cites the work of Rachel Jewkes, who shows that just over half of women and men in rural areas experience emotional abuse.

“ACEs pose a significant public-health threat, particularly in low- and middle-income countries,” says Manyema.  

She notes that the illnesses associated with higher ACE scores are entirely preventable. “The ACE scores are a fairly new tool, and so it isn’t a mandatory test in hospitals and child-care centres. We know, however, that the best time to intervene is in early childhood. Our research starts the conversation about the link between early adversity and poor health in adulthood, and informs policy across many sectors, including criminal justice, education, health and social development.”

A solid intervention, notes Manyema, is the building of resilience through strong social relationships. Resilience is evident when a person feels they have a degree of control over their circumstances and a strong ability to self-regulate.

“Overwhelming research shows that at least one caring and supportive relationship between a child and a caregiver is critical. This insight can inform a number of interventions, she says.

The ACE study questionnaire

The original questions are:

  1. Did a parent or other adult in the household often swear at you, insult you or put you down, or humiliate you or act in a way that made you afraid you might be physically hurt?
  2. Did a parent or other adult in the household often push, grab, slap or throw something at you?
  3. Did an adult or person at least five years older than you ever touch or fondle you or have you touch their body in a sexual way? Or attempt or actually have oral, anal or vaginal intercourse with you?
  4. Did you often feel that no-one in your family loved you or thought you were important or special? Or that your family didn’t look out for each other, feel close to each other, or support each other?
  5. Did you often feel that you didn’t have enough to eat, had to wear dirty clothes and had no-one to protect you? Or that your parents were too drunk or high to take care of you or take you to the doctor if you needed it?
  6. Were your parents ever separated or divorced?
  7. Was your mother or stepmother often pushed, grabbed, slapped, or had something thrown at her? Or sometimes kicked, bitten, hit with a fist or hit with something hard? Or repeatedly hit over at least a few minutes or threatened with a gun or knife?
  8. Did you live with anyone who was a problem drinker or alcoholic or who used street drugs?
  9. Was a household member depressed or mentally ill, or did a household member attempt suicide?
  10. Did a household member go to prison?