Experiencing violence and abuse in early life can lead to faster aging later in life, both mentally and physically.
A new study from the American Psychological Association explains that experiencing trauma associated with violence early on impacts the way our bodies age throughout our lives. The researchers note this process happens in three indicators of biological aging: onset of puberty, the cellular aging process, and brain development.
“Exposure to adversity in childhood is a powerful predictor of health outcomes later in life — not only mental health outcomes like depression and anxiety, but also physical health outcomes like cardiovascular disease, diabetes, and cancer,” said Katie McLaughlin, PhD, associate professor of psychology at Harvard University and senior author of the study.
“Experiencing violence can make the body age more quickly at a biological level, which may help to explain that connection.”
It’s not the first time researchers are looking into the link between a hard childhood and the speed of aging. However, they looked at several indicators of biological aging and different types of adversity together (such as violence, neglect, poverty, abuse. They found a link, but due to their structure, we couldn’t exactly tell what was causing what.
To get a clearer idea of what’s happening, the team performed a meta-analysis of over 80 studies (more than 116,000 participants in total) and teased apart threat-related adversity, such as abuse and violence, and deprivation-related adversity, such as neglect or poverty.
Children who experienced threat-related trauma were more likely to enter puberty early, the team explains, and show signs of accelerated cellular aging. One of the most telling signs of this latter type of aging was shortened telomeres, which are protective caps placed on the ends of DNA strands to keep them from breaking down. Children who experienced poverty or neglect, meanwhile, didn’t show early signs of aging.
The team then also looked at a further 25 studies (over 3,250 participants in total) to see how adversity in early life impacted later brain development. They did find it was associated with reduced cortical thickness, which is a sign of aging. Our cortices house most of our brain’s processing power and virtually all its higher functions, and are known to degrade as we get older.
However, the team did find that the exact type of adversity we experience as kids leads to thinning in a different area of the cortex. Trauma and violence affected the ventromedial prefrontal cortex in particular, which is involved in social and emotional processing. Deprivation was more often associated with thinning in the frontoparietal, default mode, and visual networks (involved in processing sensory information and other cognitive tasks).
As to why this process takes place, McLaughlin believed that maturing earlier could help ensure your survival in a violent, threat-filled environment. Alternatively, reaching puberty more early in such a setting would allow more people to possibly procreate. So they do have their uses — but in the modern world, they can lead to health complications later in life.
All of the studies worked with children and adolescents under age 18.
“The fact that we see such consistent evidence for faster aging at such a young age suggests that the biological mechanisms that contribute to health disparities are set in motion very early in life. This means that efforts to prevent these health disparities must also begin during childhood,” McLaughlin said.
The next step for the team is to investigate whether treatments aimed at children who have experienced trauma can help prevent or slow down this pattern of early aging.
The paper “Biological Aging in Childhood and Adolescence Following Experiences of Threat and Deprivation: A Systematic Review and Meta-Analysis” has been published in the journal Psychological Bulletin.