While it may not come as a surprise that survivors of childhood traumas have more difficult lives, a new study says that those children can also expect their lives to be on average, almost 20 years shorter.
A new study from the Centers for Disease Control and Prevention shows that children who experience six or more traumatic events in their childhood -- events that can include emotional, physical or sexual abuse or household dysfunction -- have an average lifespan 19 years shorter than those of their counterparts who do not suffer that degree of childhood trauma.
"The stressors tend to accumulate in people's lives, and it appears that affects the way they develop and can affect the way they think and their emotional control," said Dr. Robert Anda, who has served as the co-primary investigator on the CDC's Adverse Childhood Experiences (ACE) study.
That stress, he said, functions "like a dose of stress poison that negatively affects how the brain develops and multiple organ systems function," and can ultimately lead to the early deaths observed in the study.
For their research, investigators followed over 17,000 adults on whom they collected health behavior and status data in 1995 through 1997. In 2006, they followed up to see which of the individuals surveyed has passed away. They found that people who reported six or more adverse childhood events lived for an average of 60 years, while those who reported fewer lived, on average, to be 79.
"They tend to take on the risk factors that lead to poor health," said Anda of childhood trauma survivors. "They smoke more, they are more likely to abuse alcohol, use illicit drugs…or to be overweight or to be physically inactive."
Also, he said, "They're twice as likely to die by 65 years than people who had none of those adverse childhood experiences."
While saying the message of the study -- that childhood trauma has deep and lasting effects -- was an important one, at least one researcher stressed that childhood trauma does not preordain later problems.
"People vary immensely in their resilience," said Judith Myers-Walls, an associate professor of developmental studies at Purdue University. "There are differences related to temperament, the response of others to the event, and the resources available to the child and family. Some children even experienced concentration-camp life during the Holocaust and emerged psychologically and physically healthy."
But other researchers stressed that people have assumed too much about the fortitude of youths.
"People used to think that children were resilient by virtue of being young," said Dr. Victor G. Carrion, director of the Early Life Stress Research Program at Stanford University. "The reality cannot be further from the truth. The younger you are the more vulnerable you are to the effects of trauma."
While this research showed earlier death among the population, doctors noted that past research has shown how trauma in childhood can affect the body later in life.
Anda said the childhood stress could lead the body to produce more adrenaline and cortisol.
Anda noted that adrenaline, a neurotransmitter, could disrupt growth of the brain. And cortisol, a stress hormone, could cause other problems if secreted in excess.
"In higher doses, or if it's repeated, [it] is disruptive to nerve cell growth," said Anda. "The growth and connection between nerve cells can be disrupted in small or big ways."
Ultimately, he said, excess amounts of adrenaline and cortisol could affect how people felt years later, and other effects have been suspected.
"It appears as though it affects immune function," he said.
Other researchers affirmed those findings.
"Traumatic stress early in life can impair the development of sensitive physiological systems and neurological networks," said Carrion. "We know from our research that early life stress can alter hormonal systems and brain function."
At the same time, the psychological effects alone can signal a shortened lifespan after a negative childhood.
"The [effects] of traumatic experience usually involves severe disregulation of emotional functioning," said Felipe Amunategui, an assistant professor in the division of child and adolescent psychiatry at Case Western Reserve University in Cleveland, Ohio. "This alone is associated with interpersonal difficulties, academic underachievement, and a problematic pattern of substance use. All these factors alone are associated with a reduced life expectancy. Add them together and they conspire so seriously limit life expectancy."
While researchers attempted to limit confounding factors, it is unclear how much of the shortened lifespan of childhood trauma sufferers owes to the trauma and how much arises from other factors in childhood.
"When we think about childhood trauma, it is important to consider the sorts of environments that give rise to these kinds of difficult experiences," said Rahil Briggs, an assistant professor of pediatrics at Montefiore Medical Center in New York. "It is likely that there were a host of other risk factors present in those environments, such as neglect, exposure to second hand smoke, etc., all of which may have also affected the reduction in lifespan."
"Children who live in communities where they are exposed to [childhood traumas] may also experience other socioeconomic disadvantages, such as problems with nutrition, lack of early recognition by pediatricians and lack of environmental stimulation," said Carrion. "However these factors may be inherent in the definition of having a history of high [levels of childhood trauma]."
He noted that many most people in the CDC study were in a similar health care program, which may limit that variation.
Anda acknowledged these limitations on the study. "Probably people that have a lot of adverse childhood experiences have a lot of other events we didn't measure," he said.
At the same time, he said, childhood traumas can lead to poor life decisions, and so many of those other factors that would shorten lifespan arise because of the negative events in childhood. However, he said,
Unfortunately, Anda said, the ACES study does not have an intervention arm to see what can be done to limit the impact of a traumatic childhood.
But, he said, some things have been tried that result in a better outcome for children who would otherwise be affected by a bad home life. One example is a home visitation program by a nurse who works with the family to assess the risk of certain problems in the home. Such programs have seen a reduction in child abuse risk.
"That's one very promising venue," said Anda, "and I think we need to find others that can be broadly applied to every family."
Briggs noted that intervention can be a critical step, but prevention even more so.
"Early intervention is incredibly important, and often helps to ameliorate the effects of trauma," she said. "When we can identify children in need of help early on, and get them those needed services, we are giving them the best chance at recovery. However, prevention is even more important, as there may come a time when, even with intervention, the risk factors are too many and overwhelm the child's capacity to recover."
However, as Myers-Walls noted, a traumatic childhood can be overcome.
"I think it is important to realize that events that occur early in life are important and should not be overlooked. But it is also important to realize that these trends do not predict individual cases," she said.
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