ADHD, disruptive behaviour disorders and aggression: It’s in the genes

Having trouble setting priorities, getting organised, starting something and then staying focused on it? These are all symptoms of ADHD, a common behavioural disorder affecting about 5 % of children in Europe. On top of that, children with ADHD often simultaneously suffer from other conditions such as DBDs that can seriously impact their daily life.

“Certain people feature two or more psychiatric disorders,” states researcher Marta Ribasés of the Vall d’Hebron Research Institute in a news item posted on the ‘EurekAlert!’ website. “Tthis 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,” continues Ribasés, who is co-author of a recent study supported by the EU-funded AGGRESSOTYPE, CoCA and Eat2beNICE projects.

When co-occurring, ADHD and DBDs are said to increase the risk of drug addiction, psychiatric hospitalisation, risky behaviour and premature death, compared to ADHD on its own. Taking the first step towards a better understanding of the biological mechanism underlying comorbid ADHD and DBDs, the study explores the risk genetic factors shared between people with both disorders. The findings have been published in the journal ‘Nature Communications’.The research team examined data from different genome-wide association studies on co-occurring ADHD and DBDs. The meta-analysis of 3 802 cases and 31 305 controls resulted in the identification of 3 genome-wide significant loci for comorbid ADHD and DBDs, located on chromosomes 1, 7 and 11. The locus on chromosome 11 was linked to a higher risk of having ADHD combined with a DBD, and the associated aggressive and disruptive behaviour. “This region has the STIM1 gen, which is involved in the regulation of calcium cell levels, neuronal plasticity and learning memory,” observes co-author Bru Cormand of the University of Barcelona in the ‘EurekAlert!’ news item.

Prof. Cormand goes on to say: “Our study shows that genetics are more determining in people with ADHD and DBD than those who only suffer from ADHD. 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 ADHD and DBD patients would probably correspond to alterations other authors had related to aggressive-related behaviours.”

The results of the research supported by the AGGRESSOTYPE (Aggression subtyping for improved insight and treatment innovation in psychiatric disorders), CoCA (Comorbid Conditions of Attention deficit / hyperactivity disorder), and Eat2beNICE (Effects of Nutrition and Lifestyle on Impulsive, Compulsive, and Externalizing behaviours) projects will help to further scientists’ understanding of these co-occurring disorders. “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,” concludes Ribasés.

For more information, please see:

AGGRESSOTYPE project website

CoCA project website

Eat2beNICE project website