Teens who suffer or witness violence undergo physiological changes that can affect their physical and emotional health for years, researchers report.
The study of 115 teens found that those exposed to violence -- either as victims or witnesses -- had higher blood pressure and heart rates and increased levels of cortisol, a "fight or flight" hormone that regulates a number of important body functions.
"The risk factors of higher blood pressure, heart rate and cortisol have been associated with cardiovascular problems later in life such as hypertension and atherosclerosis," study co-author Edith Chen, of the University of British Columbia, Vancouver, said in a prepared statement.
She and her colleagues also found that, the more teens were exposed to violence, the greater their decrease in cardiovascular response. This suggests a "numbing" effect, the researchers said -- the more they're exposed to violence, the less teens react to it on cardiovascular testing.
This numbing response "suggests a deregulated physiological system, such that individuals may not be able to mount appropriate physical responses to future stressors they encounter later in life," Chen said.
The study found that white teens reported lower rates of exposure to violence than black teens and that white teens had lower baseline heart rate variability and higher cortisol levels than black teens.
"Our results suggest that exposure to violence can be conceptualized as a chronic stressor that is internalized and has lasting effects on basal neuroendocrine and cardiovascular systems of adolescents," the study authors wrote.
The study findings appear in the October issue of the Annals of Behavioral Medicine.
More information
The American Psychological Association has more about youth violence.
