ADHD, Suicidal Behavior May Share Genetic Risk Factors

the Psychiatry Advisor take:

Shared genetic risk factors may help explain the association between attention-deficit/hyperactivity disorder and heightened suicide risk, according to researchers.

In a matched cohort study that involved 51,707 patients with ADHD and their relatives, those with ADHD had a significantly increased risk for attempted (odds ratio, 3.62; 95% CI: 3.29-3.98) and completed suicide (OR, 5.91; 95% CI: 2.45-14.27), Therese Ljung, PhD, of the Karolinska Institutet in Stockholm, Sweden, and colleagues reported.

Suicide risk was also significantly higher among first-degree family members, including parents and siblings of patients with ADHD. The findings were significant across sexes, and after excluding relatives with ADHD, suicidal behavior, and those with severe comorbid disorders:

• Attempted suicide risk among parents -- OR, 2.42; 95% CI: 2.17-2.40
• Attempted suicide risk among full siblings  -- OR, 2.28; 95% CI: 2.17-2.40
• Completed suicide risk among parents --  OR, 2.24; 95% CI: 2.06-2.43
• Completed suicide risk among full siblings -- OR, 2.23; 95% CI: 1.83-2.73

The risk was much lower for genetically distant relatives, such as maternal and paternal half siblings and cousins.

“The pattern of familial risks across different levels of relatedness suggests that shared genetic factors are important for this association," the researchers wrote.

"This is an important first step toward identifying the underlying mechanisms for the risk of suicidal behavior in patients with attention-deficit/hyperactivity disorder and suggests that individuals with attention-deficit/hyperactivity disorder and their family members are important targets for suicide prevention and treatment.”