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Developmental biology - Effects of Violence

Violence In Childhood Accelerates Aging

Children who suffer abuse are more likely to age faster...

Children who suffer abuse are more likely to age faster, while those who endure food insecurity or neglect can develop more slowly, according to new research led by the University of Washington.

The study finds violence, psychological or emotional abuse, deprivation and neglect, all adverse childhood experiences, can affect both epigenetic (at the cell level) aging and biological development. It also 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. Our findings suggest that some forms of early adversity accelerate the aging process beginning very early in life, and may contribute to the high rates of health problems commonly observed among children who experience adversity."

Katie McLaughlin PhD, Assistant Professor, Harvard University. Previously with the Department of Psychology, University of Illinois at Urbana-Champaign.

The study "Early Experiences of Threat, But Not Deprivation, Are Associated With Accelerated Biological Aging in Children and Adolescents" is published online in Biological Psychiatry.

Nearly 250 children and teens, ages 8 to 16, participated in the research. 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 each child had entered at the time of their interview. Researchers examined the associations between types of adversity with epigenetic or cellular age, as well as with the child's development of puberty.

Of the participants, about twenty-five percent said they had experienced sexual abuse, and about 42 percent had experienced physical abuse. Forms of food and social deprivation were slightly less common in the study pool. For example, only about 16 percent had experienced food insecurity. In all, 48 percent of participants were girls, 61 percent were youth of color, and 27 percent were low-income. Participants with higher exposure to violence exhibited an older epigenetic or cellular age and more advanced pubertal development than expected given the child's chronological age.
Research found that children and teens who suffered physical or sexual abuse were developing faster than those who had not. This relationship could not be explained by race, ethnicity or socioeconomic status, conditions which have been related to early onset puberty.

There is a theory in the study of Life History that suggests humans, as well as other living organisms, exposed to threats at a young age, might react biologically by maturing faster in order to reach reproductive maturity. Girls, for example, might start menstruating at a younger age. At the same time, this theory holds, bodies of young people who live in food deprived environments respond by conserving resources and delaying puberty. The authors believe their new study is consistent with that theory.

Additionally, researchers looked at potential links of cellular aging and pubertal development with symptoms of depression and found that accelerated epigenetic aging is associated with higher levels of depression, which explains the association between exposure to violence and depressive symptoms. Among adults, accelerated epigenetic age has been linked to cancer, heart conditions, obesity and cognitive decline. Early onset of puberty has been associated with negative health outcomes later in life. Researchers are now exploring whether interventions with these young people, while they're young, affect their health as adults.

McLaughlin adds: "Accelerated epigenetic age and pubertal stage could be used to identify youth 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. It could be used to identify youth who may need more intensive health services."

Recent conceptual models argue that early life adversity (ELA) accelerates development, which may contribute to poor mental and physical health outcomes. Evidence for accelerated development in youths comes from studies of circuits involved in emothional processing. It is unclear whether all ELA is associated with accelerated development across global metrics of biological aging or whether this pattern emerges following specific adversity types.

In 247 children and adolescents 8 to 16 years of age with wide variability in ELA exposure, we evaluated the hypothesis that early environments characterized by threat, but not deprivation, would be associated with accelerated development across two global biological aging metrics: DNA methylation (DNAm) age and pubertal stage relative to chronological age. We also examined whether accelerated development explained associations of ELA with depressive symptoms and externalizing problems.

Exposure to threat-related ELA (e.g., violence) was associated with accelerated DNAm age and advanced pubertal stage, but exposure to deprivation (e.g., neglect, food insecurity) was not. In models including both ELA types, threat-related ELA was uniquely associated with accelerated DNAm age ( = .18) and advanced pubertal stage ( = .28), whereas deprivation was uniquely associated with delayed pubertal stage ( = .21). Older DNAm age was related to greater depressive symptoms, and a significant indirect effect of threat exposure on depressive symptoms was observed through DNAm age.

Early threat-related experiences are particularly associated with accelerated biological aging in youths, which may be a mechanism linking ELA with depressive symptoms.

Other authors on the paper were Jennifer Sumner, Center for Behavioral Cardiovascular Health at Columbia University Irving Medical Center; Natalie L. Colich, Harvard University; Monica Uddin and Don Armstrong, University of Illinois. The study was funded by the National Institutes of Health.

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Nov 13, 2018   Fetal Timeline   Maternal Timeline   News   News Archive

Research finds symptoms of depression accelerate epigenetic (or cellular) aging and are associated with exposure to violence. Credit: public domain.

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