More than 6.4 million U.S. children have received a diagnosis of attention-deficit/hyperactivity disorder, according to the Centers for Disease Control and Prevention. Despite the prevalence of ADHD, researchers continue to search for answers about what causes the disorder, why it affects children differently, and how to best treat each individual case.
Related Story: How childhood trauma could be mistaken for ADHD
Three very different studies show the potential for scientific research to offer fresh insight into these unanswered questions.
- The first study, published in a recent issue of the Journal of Child Psychology and Psychiatry, found that the condition might be influenced by a child’s socioeconomic environment.
- Meanwhile, in 2012, scientists looked at how parenting style affected behavior in children who possessed genotypes associated with ADHD. Their findings, published in the Journal of Abnormal Child Psychology, revealed that negative parenting predicted inattention symptoms in certain children.
- Finally, in the third study, which is currently unpublished, U.C. Berkeley researchers tracked and analyzed long-term outcomes for girls who were both diagnosed with ADHD and experienced severe abuse or neglect. The results indicate that experiencing ADHD and trauma may put some youth at an increased risk for eating disorders, depression and suicide later in life.
Study #1: Dr. Ginny Russell and her colleagues at the University of Exeter set out to better understand how a child’s socioeconomic standing might play a role in the development of ADHD. Russell firmly believes that ADHD is indeed a brain disorder with genetic underpinnings, but she also worries that it has been characterized as a “context-free condition.” Time and again, studies have shown that poor or disadvantaged children are more likely to have ADHD, and this fact struck Russell.
Some researchers have argued that this increased likelihood could be the result of reverse causality, or in other words, that the difficulty of parenting a child with behavioral problems might lead to economic hardship and divorce. In Russell’s study, which used data from a longitudinal study of more than 19,000 children in the United Kingdom, low-income families were more likely to have a child with ADHD – but that couldn’t be traced back to reverse causality. In fact, household income for families with an ADHD-diagnosed child didn’t decline over a period of several years compared to families without a diagnosis. Both sets of families had matching earnings at the start.