Children with more internalizing mental health problems, as well as those with more aggressive behaviors, tend to have higher DNA-methylation indicators, indicating a faster pace of biological aging, according to new research. Children from families of higher socioeconomic status and White families tend to have a slower pace of biological aging. The study was published in Clinical Psychological Science.
DNA methylation indicators are biomarkers based on the methylation patterns of DNA, which involve the addition of methyl groups to the DNA molecule. These chemical groups, consisting of one carbon atom bonded to three hydrogen atoms (–CH₃), regulate gene expression by turning genes on or off without changing the underlying DNA sequence. Studies have shown that these methylation changes are associated with aging.
Using this knowledge, scientists have developed methods to use DNA methylation data to calculate an individual’s biological age. Biological age reflects an individual’s physiological and functional state, influenced by lifestyle, genetics, and environmental factors. Unlike calendar age, which is simply the number of years a person has lived, biological age can be higher or lower depending on one’s health and aging processes.
Study author Laurel Raffington and her colleagues aimed to examine whether DNA methylation alterations related to inflammation and aging were associated with the mental health of children, as well as their racial/ethnic background and socioeconomic status. They focused on indicators of biological aging pace and systemic low-grade inflammation derived from DNA methylation patterns.
The researchers analyzed data from the Texas Twin Project, which included 1,183 twins recruited from public school rosters in central Texas. The participants, aged 8 to 19, included 609 females, 426 monozygotic twins, and 757 dizygotic twins from 617 different families. Among them, 195 provided two DNA methylation samples collected 3 to 38 months apart.
In addition to DNA methylation data indicating biological age and low-grade systemic inflammation, the researchers used mental health data from the Achenbach Child Behavior Checklist completed by parents, as well as symptom counts. They also collected sociodemographic data, including measures of socioeconomic disadvantage at the neighborhood and family levels, and racial/ethnic identities.
The results showed that children from more disadvantaged neighborhoods generally had worse mental health symptoms across all domains except conduct disorder, with more internalizing and attention problems. Parents of Latinx and Black children reported more internalizing and attention problems compared to parents of White children. Internalizing problems include issues such as anxiety, depression, and social withdrawal.
Self-reported mental health assessments from the children also indicated worse mental health in those from more disadvantaged neighborhoods, though the association was weaker compared to parent-reported data. When using child-reported mental health indicators, there were no significant associations between race and mental health.
Higher DNA methylation indicators of biological age and systemic inflammation were found in children whose parents reported severe internalizing problems. Similarly, a higher biological age was observed in children reported to be more aggressive by their parents. There were no significant associations between child-reported mental health indicators and DNA methylation indicators.
“Our findings suggest that salivary DNA-methylation patterns of higher inflammation and faster pace of biological aging originally developed in adults are economically and racially stratified and are associated with child mental health. Because saliva can easily be collected in large-scale pediatric epidemiological studies and may indicate emerging health conditions, these DNA-methylation algorithms may be employed in research seeking to understand and prevent economic and racial disparities in childhood mental health,” the study authors concluded.
The study sheds light on the links between mental health in children and DNA-methylation indicators of age and inflammation. However, it is important to note that these associations were primarily based on parent reports, which could be influenced by reporting bias. Different parents might apply different reporting strategies, potentially affecting the results.
The paper, “Associations of DNA-Methylation Measures of Biological Aging With Social Disparities in Child and Adolescent Mental Health,” was authored by Laurel Raffington, Peter T. Tanksley, Liza Vinnik, Aditi Sabhlok, Megan W. Patterson, Travis Mallard, Margherita Malanchini, Ziada Ayorech, Elliot M. Tucker-Drob, and Kathryn Paige Harden.
