Violence, psychological or emotional abuse, and deprivation or neglect during childhood can affect both cellular aging and biological development, according to a new study.
Further, the study shows that different forms of adversity during childhood have different impacts on the aging process.
“Exposure to violence in childhood accelerates biological aging in children as young as 8 years old,” says Katie McLaughlin, who led the study while on the faculty of the psychology department at the University of Washington and is now an assistant professor at Harvard University.
“Our findings suggest that some forms of early adversity accelerate the aging process beginning very early in life, which may contribute to the high rates of health problems commonly observed among children who experience adversity,” McLaughlin says.
Nearly 250 children and teens, ages 8 to 16, participated in the study. Through child and parent interviews and surveys, as well as saliva samples for DNA analysis, researchers determined the number and type of adverse life events each child had experienced, along with the stages of puberty they had entered. The researchers examined the associations between types of adversity with epigenetic, or cellular, age, and pubertal development.
Of the participants, about one-quarter said they had experienced sexual abuse, and about 42 percent had experienced physical abuse. Forms of deprivation were slightly less common in the study pool, for example: About 16 percent said they had experienced food insecurity. In all, 48 percent of participants were girls, 61 percent were youth of color, and 27 percent were low-income.
On the defense
As reported in Biological Psychiatry, participants with higher exposure to violence exhibited an older epigenetic or cellular age as well as more advanced pubertal development than what would be expected given the child’s chronological age.
In other words, children and teens who suffered abuse were developing faster than those who had not. Differences in race/ethnicity or socioeconomic status, which also have been related to the early onset of puberty, did not explain these relationships.
Life history theory, the paper points out, suggests that humans (and other living organisms) who are exposed to threats at a young age might react biologically by maturing faster to reach reproductive maturity. Girls, for example, might start menstruating at a younger age.
At the same time, the theory holds, the bodies of young people who live in deprived environments respond by conserving resources and delaying reproductive development. The new findings are consistent with that theory, the authors write.
In addition, the researchers looked at potential links of cellular aging and pubertal development with symptoms of depression. The study found that accelerated epigenetic aging was associated with higher levels of depression, and helped to explain the association between exposure to violence and depressive symptoms.
Among adults, accelerated epigenetic age has been linked to cancer, cardiovascular conditions, obesity, and cognitive decline. And early onset of puberty has been associated with negative health outcomes later in life. Researchers are exploring whether interventions with these young people, while they’re young, affect their health as adults.
“Accelerated epigenetic age and pubertal stage could be used to identify youth who are developing faster than expected given their chronological age and who might benefit from intervention,” McLaughlin says.
“Pubertal stage is an especially useful marker because it is easy and inexpensive to assess by health care providers, and could be used to identify youth who may need more intensive health services,” she says.
About the Authors
Katie McLaughlin, led the study while on the faculty of the psychology department at the University of Washington. She is now an assistant professor at Harvard University.
Additional authors are from Columbia University Irving Medical Center, Harvard, and the University of Illinois. The National Institutes of Health funded the work.
Source: University of Washington