Patients With a Combination of ADHD and DBD Share Genetic Factors Linked to Risky, Aggressive Behavior

Individuals with both attention-deficit/hyperactivity disorder (ADHD) and a disruptive behavior disorder (DBD) share about 80% of genetic variants associated with aggressive and antisocial behaviors, according to new research published in Nature Communications. The study analyzed nearly 4000 patients with these pathologies and 30,000 control individuals, examining the neurobiological basis for aggressive behavior.

“Certain people feature 2 or more psychiatric disorders, and this coexistence continues, in many cases, in a chronological axis, in which suffering from a psychiatric disorder such as ADHD involves opening the door to other comorbid pathologies that aggravate the life quality of those who suffer from the disorder,” said Marta Ribasés, PhD, head of the Laboratory of Genetic Psychiatry of Vall d'Hebrón Research Institute (VHIR), in a press release.

ADHD affects around 5% of children and 2.5% of adults and features hyperactivity, impulsiveness, and attention deficit. It is often associated with additional psychiatric conditions, including DBDs, which can be associated with antisocial and aggressive behaviors.

“ADHD and DBD are caused by genetic and environmental factors,” said Bru Cormand, professor at the Department of Genetics, Microbiology and Statistics and head of the Research Group on Neurogenetics at the University of Barcelona, in the release. “Regarding ADHD, it is estimated that genetics account for 75%, while in DBDs, it would oscillate between 40 and 70%. These clinical pictures are more frequent in boys than girls, and when they come together, people are more likely to fall into risky behaviors, addictive substance use, and premature death.”

The investigators identified a genomic segment in chromosome 11 that increases the risk of having ADHD in combination with DBD. This region contains the STIM1 gene, responsible for the regulation of calcium cell levels, neuronal plasticity and learning memory.

“Our study shows that genetics are more determining in people with ADHD and DBD than those who only suffer from ADHD,” Cormand said in the release. “If we compare the genome of patients with ADHD and DBD to that of those patients with only ADHD, we see that people affected by both disorders have a higher genetic correlation with risk genetic variants. These extra correlations of [patients with] ADHD and DBD would probably correspond to alterations other authors had related to aggressive-related behaviors.”

According to the investigators, this study will help broaden the understanding of the genetic landscape of ADHD comorbidities, enabling the prediction of potential secondary complications for these patients.

“If we consider ADHD to be an open door to a negative trajectory, using genetic information to identify those individuals who are more vulnerable will have a strong impact on prevention, early detection, and treatment, and will shed light on new research studies to find efficient therapies that can be specific for the disorder or shared between several disorders,” Ribasés said in the release.

REFERENCE

ADHD, DBD and aggressiveness: Risky genetic factors [news release]. EurekAlert; February 17, 2021. Accessed July 13, 2021. https://www.eurekalert.org/pub_releases/2021-02/uob-ada021721.php