Individuals exposed to adverse childhood experiences tend to be biologically older than their counterparts, according to new research published in the scientific journal Psychoneuroendocrinology.
Adverse childhood experiences refer to a set of potentially traumatic events that occur before adulthood. These experiences include various forms of abuse and neglect, witnessing intimate partner violence, parental death or serious illness, parental divorce or separation, and psychiatric illness of a family member. Biological aging, on the other hand, refers to the accumulation of damage and loss of function to cells, tissues and organs.
Previous research has found that people exposed to adverse childhood experiences are more likely to suffer from chronic diseases and have a shorter lifespan. The authors of the new study were interested in whether accelerated biological aging could help explain the relationship between adverse childhood experiences and poor health outcomes later in life.
“This work was part of a team effort led by Dr. Dawn Bowdish at McMaster University to better understand the factors that influence the health trajectories of individuals over the life course,” said corresponding author Chris Verschoor, a scientist at the Health Sciences North Research Institute and assistant professor at McMaster University and the Northern Ontario School of Medicine.
“I am interested in the determinants of health and immunity of older adults, particularly how they intersect with a person’s biology. This study provided a unique opportunity to quantify how different forms of early life adversity impact the ‘biological age’ of a person 30 to 60 years later.”
The researchers analyzed data from the Canadian Longitudinal Study on Aging, a long-term study of adult development and aging, which includes 50,000 Canadians who were aged 45-85 years at the time of recruitment.
The study focused on 23,354 participants who had completed a 90-minute interview and taken part in physical and clinical assessments. The researchers examined a number of biomarkers related to the biological aging process, including albumin, creatinine, glycated hemoglobin (HbA1C), C-reactive protein, lymphocyte percentage, mean cell volume, red blood cell distribution width, and white blood cell count.
The average age of the participants was 59, and most (63%) reported experiencing at least one adverse childhood experience. Participants who reported adverse childhood experiences tended to be biologically older than those who did not. In addition, the researchers found that the link between adverse childhood experiences and biological age was stronger for more severe forms of adversity, such as physical and sexual abuse.
The findings suggest “that harms in early life can take many forms, and can lead to health consequences many years down the road,” Verschoor told PsyPost. “What our study shows is that these consequences manifest as perturbations to multiple biological systems, which can be measured from biomarkers in blood.”
But the researchers noted that nearly all of the observed effect-sizes were relatively small. Adverse childhood experiences were also associated with education level and smoking status, which in turn were related to biological age. The study authors said future research utilizing longitudinal data could help us better understand the factors linking adverse childhood experiences to biological age.
“What our study doesn’t show is whether the biological changes we detected were caused by the early life events themselves, or from other events or risky behaviors that happened later in life as a consequence,” Verschoor explained.
“As mentioned, this was a team effort and could not have happened without the participants of the Canadian Longitudinal Study on Aging and the involvement of great collaborators,” he added. “Especially, Dr. Oxana Mian, the post-doctoral fellow that performed much of the work, Dr. Dan Belsky of Columbia University and Dr. Andrea Gonzalez of McMaster University.”
The study, “Associations between exposure to adverse childhood experiences and biological aging: Evidence from the Canadian Longitudinal Study on Aging“, was authored by Oxana Mian, Daniel W. Belsky, Alan A. Cohen, Laura N. Anderson, Andrea Gonzalez, Jinhui Ma, Deborah M. Slobod, Dawn ME Bowdishg, and Chris P. Verschoor.