A recent analysis of data held in the National Institute of Mental Health Data Archive (NDA) found that children aged 9-11 whose mothers were between 15 and 19 years of age when the children were born displayed more behavioral problems then children of older mothers. Researchers found these problems to be related to lower volumes of certain areas of the brain. The study used the data from the ABCD Study annual release 2.01 and was published in Molecular Psychiatry.
A higher childbearing age has been the trend throughout the world in recent years. In spite of this, some 16 million adolescents between 15 and 19 years of age contribute to nearly 11% of all childbirths. Recent studies have shown that older parental age is associated with fewer behavior problems and better cognitive performance in children.
Jingnan Du from Harvard University and his colleagues analyzed data from the Adolescent Brain Cognitive Behavior study (ABCD), “the largest long-term study of brain development and child health ever conducted in the United States” that recruited children across 21 research sites. A total number of 11897 children aged between 9 and 11 years were involved in the part of the study. Researchers analyzed data from 8709 of these children.
Their goal was to study the relationship between parental age (age of the parent at the moment the child was born) and children’s behavioral problems and cognitive performance. Another goal was to assess whether there are differences in the brain volumes and cortical areas of different brain regions associated with age of parents. Finally, they wanted to find out whether the relationship between parental age and behavioral and cognitive problems can be attributed to the observed differences in children’s brains.
The analyzed data on the maternal and paternal ages of each child’s parents (their age at the time the child was born). Researchers found these to be very similar (ages of mother and father at the time the child was born) and decided to examine them together. The database also contained results of cognitive performance assessments conducted using 10 different cognitive tests and of behavioral problems assessments based on the Parent Child Behavior Checklist Scores. This questionnaire contains eight syndrome scales related to psychiatric problems such as depression, social problems, rule-breaking behavior, social problems, aggressive behavior and a few others.
Researchers divided the children into 14 groups based on the children’s maternal age and compared these groups. Overall scores on behavioral problems were higher in children whose maternal ages were between 15 and 19 compared to groups with older maternal age. Overall cognitive performance scores were lower in children whose mothers were very young at the time of their birth (15-19) compared to children who were born to older mothers. Similar results were reproduced for the age of fathers at the time children were born.
Additionally, researchers found that children with smaller areas and volumes of the studied brain regions had more behavioral problems (as assessed by the behavioral problems total score) and worse cognitive performance results. Study authors found that volume and area of studied brain regions mediates the association between maternal age and both behavioral problems and cognitive performance.
The study brings to light important relations, but authors emphasize that “the findings described here are associations”, not cause-and-effect relationships, and that their origin needs to be the subject of future research. Notably, the youngest two maternal age groups were teenaged mothers and it could be that mothers who are 15-19 might have had behavioral problems themselves before they became mothers. In this way, “the effects found could be related to genetic effects or to the environment in which the children were brought up”.
The study “Association between parental age, brain structure, and behavioral and cognitive problems in children” was authored by Jingan Du, Edmund T. Rolls, Weikang Gong, Miao Cao, Deniz Vatansever, Jie Zhang, Jujiao Kan, Wei Chang and Jianfeng Feng.
