Meta-analysis Reports ADHD More Than Triples Odds of Suicidal Behavior in Youth

Suicide is one of the most feared outcomes of any psychiatric condition. Although its association with depression is well known, a small but growing research literature shows that ADHD is also a risk factor for suicidality.  Suicide is difficult to study. Because it is relatively rare, large samples of patients are needed to make definitive statements.
Studies of suicide and ADHD must also consider the possibility that medications might elevate that risk. For example, the FDA placed a black box warning on atomoxetine because that ADHD medication had been shown to increase suicidal risk in youth.  A recent study of 37,936 patients with ADHD now provides much insight into these issues (Chen, Q., Sjolander, A., Runeson, B., D'Onofrio, B. M., Lichtenstein, P. & Larsson, H. (2014). Drug treatment for attention-deficit/hyperactivity disorder and suicidal behavior: a register-based study. BMJ 348, g3769.). In Sweden, such large studies are possible because researchers have computerized medical registers that describe the disorders and treatments of all people in Sweden. Among 37,936 patients with ADHD, 7019 suicide attempts or completed suicides occurred during 150,721 person-years of follow-up. This indicates that, in any given year, the risk for a suicidal event is about 5%. For ADHD patients, the risk for a suicide event is about 30% greater than for non-ADHD patients. Among the ADHD patients who attempted or completed suicide, the risk was increased for those who had also been diagnosed with a mood disorder, conduct disorder, substance abuse, or borderline personality. This is not surprising; the most serious and complicated cases of ADHD are those that have the greatest risk for suicidal events. The effects of the medication were less clear.  The risk for suicide events was greater for ADHD patients who had been treated with non-stimulant medication compared with those who had not been treated with non-stimulant medication. A similar comparison showed no effect of stimulant medications. This first analysis suffers from the fact that the probability of receiving medication increases with the severity of the disorder. To address this problem, the researchers limited the analyses to ADHD patients who had some medication treatment and then compared suicidal risk between periods of medication treatment and periods of no medication treatment. This analysis found no increased risk for suicide from non-stimulant medications and, more importantly, found that for patients treated with stimulants, the risk for suicide was lower when they were taking stimulant medications. This protective effect of stimulant medication provides further evidence of the long-term effects of stimulant medications, which have also been shown to lower the risks for traffic accidents, criminality, smoking, and other substance use disorders.

In the general population, most mothers experience mood disturbances right after childbirth, commonly known as postpartum blues, baby blues, or maternity blues. Yet only about one in six develop symptoms with a duration and magnitude that require treatment for depressive disorder, and one in ten for anxiety disorder.

To what extent does ADHD contribute to the risk of such disorders following childbirth? A Swedish study team used the country’s single-payer health insurance database and other national registers to conduct the first nationwide population study to explore this question.

They used the medical birth register to identify all 420,513 women above 15 years of age who gave birth to their first child, and all 352,534 who gave birth to their second child, between 2005 and 2013. They excluded miscarriages. They then looked for diagnoses of depression and/or anxiety disorders up to a year following childbirth.

In the study population, 3,515 mothers had been diagnosed with ADHD, and the other 769,532 had no such diagnosis. 

Following childbirth, depression disorders were five times more prevalent among mothers with ADHD than among their non-ADHD peers. Excluding individuals with a prior history of depression made little difference, lowering the prevalence ratio to just under 5. Among women under 25, the prevalence ratio was still above 3, while for those 25 and older it was above 6.

Similarly, anxiety disorders were over five times more prevalent among mothers with ADHD than among their non-ADHD peers. Once again, excluding individuals with a prior history of depression made little difference, lowering the prevalence ratio to just under 5. Among women under 25, the prevalence ratio was still above 3, while for those 25 and older it was above 6.

The team cautioned, “There is a potential risk of surveillance bias as women diagnosed with ADHD are more likely to have repeated visits to psychiatric care and might have an enhanced likelihood of also being diagnosed with depression and anxiety disorders postpartum, compared to women without ADHD.”

Nevertheless, they concluded, “ADHD is an important risk factor for both depression and anxiety disorders in the postpartum period and should be considered in the post- pregnancy maternal care, regardless of sociodemographic factors and the presence of other psychiatric disorders. Parental education prior to conception, psychological surveillance during, and social support after childbirth should be provided to women diagnosed with ADHD.”

Children with disabilities are known to be at heightened risk of violence compared to their non-disabled peers. To what extent does this hold true for ADHD?

Denmark has a single-payer health insurance system through which health data about virtually the entire population can be cross-referenced with population, crime, welfare, and other registers through unique individual person numbers.

A Danish study team accessed national registers to examine the relationship between ADHD and criminal victimhood among nine yearly birth cohorts totaling more than 570,000 children and adolescents. 

Of these, 557,521, among them 12,040 with ADHD, were not reported as being exposed to violence, and 12,830, among which 1,179 with ADHD, were exposed to violence.

From the raw data, children and adolescents with ADHD were more than four times as likely to be exposed to violence than their typically developing peers.

The team then adjusted for other disabilities, family risk factors, gender, birth year, and ethnic background.

With these confounders out of the way, children and adolescents with ADHD remained more than twice as likely to be exposed to violence than their typically developing peers.

To place this outcome in further perspective:

• Brain injuries increased the odds of being exposed to violence by over 75% relative to typically developing peers.
• Physical and speech disabilities raised the odds by a bit over 35%.
• Intellectual and sensory disabilities, dyslexia, and congenital malformations had no effect. 
• Epilepsy reduced the odds of being exposed to violence by just under 20%, and autistic spectrum disorder by just over 25%.

Certain family risk factors further aggravated the odds:

• Violence in the family by more than 2.5-fold.
• Out-of-home care and breakup of parental relationship by more than 75%.

Perhaps surprisingly, substance abuse by family members had no effect whatsoever after adjusting for confounders.