Children who suffer abuse are more likely to age faster, while those who endure food insecurity or neglect may develop more slowly, according to new research led by the University of Washington.
Violence, psychological or emotional abuse, deprivation and neglect -- adverse childhood experiences -- can affect both epigenetic, or cellular, aging and biological development, the study finds. The new study links violence exposure in childhood with accelerated aging, and demonstrates 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," said Katie McLaughlin, now an assistant professor at Harvard University who led the study while on the faculty of the UW Department of Psychology. "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."
The study posted online Sept. 26 in Biological Psychiatry.
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.
The study found that 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. These relationships were not explained by differences in race/ethnicity or socioeconomic status, which also have been related to the early onset of puberty.
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 study is 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. 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," McLaughlin said.
Other authors on the paper were Jennifer Sumner of the Center for Behavioral Cardiovascular Health at Columbia University Irving Medical Center; Natalie Colich of Harvard; and Monica Uddin and Don Armstrong, both of the University of Illinois. The study was funded by the National Institutes of Health.
Adapted from a Biological Psychiatry press release.
For more information, contact McLaughlin at firstname.lastname@example.org.