Adverse Child Experiences, Brain Changes, and Diseases

Wikimedia Commons: Correlation vs. Causation by Rcragun, CC Attribution 3.0

Many studies show a correlation between adverse childhood experiences (ACEs) and various psychiatric and physical conditions. This is probably also true of the effects on offspring of certain parental behavior problems.

Correlation vs. Causation

Correlation does not mean causation. Answering the question of whether two characteristics that correlate in a study are also involved in a causative relationship depends on several factors. How strong is the correlation? A weak correlation can be a statistical fluke. If there is a lot of natural variation in the characteristics being discussed, the found relationship may just be a coincidence.

Are there other variables that are not controlled for that create the correlation? Repeated experiments that lead to the same result are necessary to verify a relationship seemingly uncovered in any given study. And even if causation is involved, we may not know which variable was the causative factor and which was the result.

The metrics I tend to use also include my answers to the following questions: If A and B are indeed causally related, what else would I have to believe? Can I think of a third, uncontrolled-for variable that could account for both A and B? Can I come up with any logical and known facts or data that might explain an apparent causative relationship, or does it seem inexplicable or even off the wall?

Last, is this result consistent with what I have seen clinically in my 40-plus years as a psychiatrist, or does it fly in the face of it? It is possible that I might be looking at only confirmatory evidence of my opinions and discounting disconfirming evidence (confirmation bias). However, I think I have at least a modicum of objectivity.

So I also ask other psychiatrists and therapists if they’ve seen the same things I have in their clinical experience. When I do that, I have to consider that I ask my patients many questions that most therapists never even think about asking. For example, “What does your mother-in-law think about this problem your daughter is having?” So they might be unable to give me any relevant information.

Many studies showing the same thing make for a stronger case for causation. Regarding ACEs and illnesses, they usually pass most, if not all, of the tests above with flying colors. And they keep on coming in. Here are some recent additions:

1. Childhood adversity is tied to race-related differences in brain development.

In this study, exposure to trauma was linked to lower gray matter volume in key brain regions in Black kids. Among children ages nine to ten years, white kids showed greater gray matter volumes compared with Black kids in the amygdala, hippocampus, frontal pole, superior frontal gyrus, rostral anterior cingulate, pars opercularis, pars orbitalis, lateral orbitofrontal cortex, caudal middle frontal gyrus, and caudal anterior cingulate (all p<0.001).

Compared with white children, Black children experienced more traumatic events, material hardship, and family conflict. They lived in more disadvantaged neighborhoods, while their parents/caregivers had lower income and educational attainment and were more likely to be unemployed.

This analysis may provide evidence that contradicts claims about inherent race-related differences found in the brain.

2. Childhood adversity is tied to cardiovascular disease in early adulthood.

A large Danish study of patients aged 16-38 has found children who experience adversity, including serious family illness or death, poverty, neglect, or dysfunctional and stressful family relationships, are at increased risk of developing cardiovascular disease (CVD) in early adulthood. The researchers found that compared to young adults who experienced little adversity in childhood, peers who experienced high levels of childhood adversity had about a 60 percent higher risk of developing CVD.

Child Development Essential Reads

How Recess May Help Your Child's Resilience

The Pain of Parent-Child Role Reversals: 4 Core Themes

3. Adolescents’ positive perceptions of their relationships with both their parents are associated with a wide range of favorable outcomes in young adulthood.

In this study of more than 15,000 adolescents, higher levels of adolescent-reported parental warmth, parent-adolescent communication, time together, academic expectations, relationship and communication satisfaction, and maternal inductive discipline were all associated with favorable outcomes in young adulthood.

Participants rated their depression, stress, optimism, nicotine dependence, substance abuse symptoms (alcohol, cannabis, or other drugs), unintended pregnancy, romantic relationship quality, physical violence, and alcohol-related injury.

This was done while controlling for age, biological sex, race and ethnicity, parental educational level, family structure, and child maltreatment experiences.