(dailyRx News) A child, like an adult, does not need to experience violence to be affected by it. Just witnessing violent events can affect a child's mental health - and possibly physical health, too.
A recent study has found that young boys exposed to violence may become desensitized to it in a physiological sense, which could have long-term health implications.
Melissa K. Peckins, MS, of the Department of Biobehavioral Health at Penn State, and colleagues investigated how exposure to violence in the community might affect children in the longer term.
They decided to measure the impact of the violent experience by looking at the cortisol levels in the children. Cortisol is a stress hormone, and past studies have shown that it remains at higher levels in children who have experienced abuse directly.
The researchers looked at 124 children, aged 8 to 13, who had witnessed or experienced a violent incident and then followed up with them a year later.
The children were predominantly white and came from small cities and rural communities instead of inner cities or highly urban areas. None had a history of being abused.
The children filled out questionnaires that asked about violent incidents they had seen or been victim of in the past 12 months.
After the questionnaire, the students were asked to perform an intentionally stressful task: to complete the end of a story prompt before two judges who would compare them to the stories of other children.
Then they completed a series of subtraction math problems. Both these experiences were designed to cause them stress, and saliva samples from the students were collected before and after the experience to measure cortisol levels.
The researchers found an inverse relationship between the amount of violence the boys had been exposed to and the amount of cortisol measured in their saliva: the more violent events they had experienced, the less cortisol was present after the study's stress tests.
In other words, the boys who had been exposed to the most violence had the least amount of stress hormone being released in a stressful situation, which means their bodies had become used to a certain basic level of stress that is above an average person's levels.
This effect was not seen in the girls included in the study.
The study's results matched up with the clinical experience of social worker LuAnn Pierce, who was not associated with this study but has worked extensively with children in her practice.
"This study offers interesting insights into the long term effects of witnessing violence," she said. "Based on my experience with children and teens who have witnesses the abuse of one parent by another, the habituated responses in males seems to be the same."
She recalled a graduate school clinical experience in which she was treating a 5-year-old boy who had repeatedly witnessed violence in his home.
He had developed Cushing's syndrome, a disease related to having excessively high levels of cortisol in the body and likely related to his constant exposure to stress at home. She said he died before his sixth birthday without any evidence of genetic or other causes.
While it may then sound like a good thing that the boys exposed to violent situations may have adapted to stress levels, there can be long-term health consequences of not producing cortisol in stressful situations as well, according to the study's authors.
"In enduring stressful conditions, we may have adapted evolutionarily to suppress our cortisol levels because higher and more prolonged levels of cortisol in the bloodstream can lead to negative health consequences, such as autoimmune disorders, lowered immunity, arthritis and atypical depression," said senior author Elizabeth J. Susman, PhD, at Penn State. "This may explain why cortisol reactivity was lower for males."
She said the different coping mechanisms that girls are often known to employ might explain the absence of this effect in the girls in the study.
"There is a theory that females may react to stressful situations by talking about it, which may be their way of reducing the negative effects of cortisol in the bloodstream," Dr. Susman said. "If parents and other adults are available to discuss episodes of violence with children, it might help the children, especially females, to reduce their cortisol levels."
The best option, of course, is prevention: keeping children from being exposed to violence in the first place, said Pierce.
"It is critical that parents learn ways to protect their children from the effects of chronic stress," she said. "Monitoring what they watch on television and video games is also critical - scary shows/games and others that contain violence create the same reaction as real life situations."
The researchers also found that a higher amount of exposure to violence among the study participants was correlated with symptoms of major depressive disorder and generalized anxiety disorder in both the girls and the boys.
Although the sample size in this study was not large, the researchers said its findings mean that further research into the long-term effects of exposure to violence should be conducted.
"We know that exposure to violence is linked with aggression, depression, post-traumatic stress symptoms and academic and cognitive difficulties in the short term, but little is known about the long-term effects of such exposure," Dr. Susman said. "Our data show that the stress reaction to violence exposure is not just immediate. There's an effect that endures."
The study will be published in an upcoming issue of the Journal of Adolescent Health. The research was funded by the National Institute of Mental Health, the National Institutes of Health, the General Clinical Research Center and the Shibley Endowment at Penn State.