woman with adhd showing confusion through illustration above head

tention-deficit/hyperactivity disorder, known as ADHD, is a common mental health condition, which recent research shows may be associated with suicide and other mental health disorders. Here are the latest statistics on the prevalence of ADHD:

  • According to the charity Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD), the global rate of ADHD among children and adolescents is about 7.2%.
  • This means that more than 129 million young people across the globe have this disorder.
  • Surveys indicate that about 4.4% of adults also have ADHD.

Due to the prevalence of this disorder, as well as the effectiveness of medications typically prescribed to treat it, most people probably view ADHD as less concerning than other mental health diagnoses.

While it is true that attention-deficit/hyperactivity disorder isn’t typically linked with the types of disruptions associated with schizophrenia, bipolar disorder, or borderline personality disorder, ADHD may lead to serious complications.

In addition to the direct, day-to-day impact that ADHD symptoms have on the ability to live a full and satisfying life, the disorder creates other serious challenges. Research shows ADHD can increase person’s risk for two significant concerns: suicide attempts and the development of other mental illnesses.

ADHD and Co-Occurring Mental Illnesses

The fact that many people with ADHD also have other mental health disorders is not news. Experts know a variety of mental health disorders commonly co-occur alongside ADHD.

For example, a 2019 article in the World Journal of Clinical Cases reported the following about co-occurring disorders among children with ADHD:

  • 42% of children diagnosed with autism spectrum disorder (ASD) also have comorbid ADHD.
  • The rate of major depressive disorder is five times higher among children with ADHD than among children without ADHD.
  • 30%-50% of children with ADHD also meet the criteria for a diagnosis of conduct disorder (CD) or oppositional defiant disorder (ODD).

For adults who have ADHD, a 2017 BMC Psychiatry article included the following information about co-occurring mental health concerns:

  • As many as 41% of adults with ADHD report comorbid bipolar disorder.
  • The estimated rate of depression among adults with ADHD ranges from 18.6%-53.3%.
  • Nearly 50% of adults with ADHD report an anxiety disorder.
  • The prevalence of substance use disorder (SUD) among people with ADHD is twice as prevalence the general population.
  • Some studies suggest that more than 50% of adults with ADHD have a co-occurring personality disorder.

Can ADHD Cause Other Mental Illnesses?

Typically, studies refer to an association between ADHD and other mental illnesses, rather than a cause-effect relationship.

In September 2023, a study on this topic made headlines because it suggested ADHD may be an independent risk factor for various other mental health conditions.

Conducted by Christa Meisinger and Dennis Freuer of the University of Augsburg, researchers focused on this goal:

“To investigate the direct and indirect causal paths between ADHD and seven common mental disorders.”

Meisinger and Freuer evaluated the following seven mental health-related areas for their relationship with ADHD:

The researchers used a technique called Mendelian randomization analysis to identify possible connections between these disorders and ADHD.

In a CNN article about this study, James Greenblatt, MD described the Mendelian technique as using “genetic variation to assess how — and how significantly — a given risk factor may influence a health outcome.”

Meisinger and Freuer conducted their analyses on data collected during two genome-wide association studies (GWAS), one conducted as part of the iPSYCH project and one from the Psychiatric Genomics Consortium (PGC). These analyses led to the following conclusions:

ADHD and Co-Morbid Menal Illness

  • They found that ADHD may have a causal impact on PTSD, anorexia, and attempted suicide.
  • The identified a bidirectional relationship between ADHD and major depressive disorder. This means that having ADHD may increase a person’s risk for MDD, and vice versa.
  • The found no statistically relevant link between ADHD and the other three conditions that were included in this study (anxiety, bipolar disorder, and schizophrenia).

“The present findings are important for clinicians treating patients with ADHD because they provide a guide as to the mental comorbidities on which to focus preventively and therapeutically during the course of the disease,” the researchers wrote. “ADHD serves as an early indicator of other mental disorders due to shared psychopathologies.”

Meisinger and Freuer also acknowledged that the genetic concerns they assessed do not determine, unequivocally, whether a person develops one of the disorders they studied. They noted that prenatal and perinatal factors also influence risk, as well prescription stimulants prescribed for ADHD symptoms.

Greenblatt explains:

“Having ADHD does not make depression (or other mental disorders) inevitable. What it does do, however, is ‘stack’ the deck of cards we’re dealt — cards like genetics, biochemistry, lifestyle, environment, and psychology — in such a way as makes certain outcomes such as depression more likely.”

ADHD and Suicide

Meisinger and Freuer aren’t the only researchers examining the influence of ADHD may on suicide risk.

In March 2017, the World Journal of Psychiatry published a systematic review of 26 papers from 2011-2015 that focused on ADHD and suicidality. This review, conducted by Judit Balazs, MD, PhD, and Agnes Kereszteny, MA, of the Institute of Psychology at Eötvös Loránd University in Budapest, Hungary, collected data from sources on four continents. This emphasized the universality ADHD, and included information on children, adolescents, and adults.

After reviewing these 26 articles, Balazs and Kereszteny reported the following:

  • 25% of children under the age of 12 with suicidal thoughts had ADHD.
  • More than 50% of adolescents with ADHD report suicidal ideation.
  • Among adults with ADHD, more than 33% report suicidal ideation.
  • 16% of adults with ADHD and about 10% of adolescents with this condition report at least one suicide attempt.

Their review, Balazs and Kereszteny wrote, “strengthens the recent finding that ADHD is related to high suicidality in all age groups.”

Though the suicidality rate is slightly higher among boys and men than among girls and women, the researchers noted individuals of all genders with ADHD have increased risk of suicide.

How Does ADHD Affect Suicidality?

While the link between ADHD and suicidality is well established, experts have not yet been able to definitively determine why people with attention-deficit/hyperactivity disorder may be more likely to end their own lives.

One possible answer to this question was put forth in a September 2020 article in the journal Science Advances. The authors of this article proposed that money problems could be a factor in elevated suicide rates among adults with ADHD.

Since ADHD can undermine a person’s ability to pay bills on a timely basis and track their saving and spending habits, individuals with this condition may be at greater risk for financial problems, the researchers wrote. This money-related stress may, in turn, increase their risk of suicidal thoughts and actions.

To test these hypotheses, the authors (one psychologist and two financial experts) analyzed data from more than 11 million adults in Sweden that had been added to a national registry between 2002-2015.

ADHD: Long-Term Outcomes

  • Self-reporting indicates that adults who have ADHD are more likely to depend on family members for financial support, have fewer savings accounts but more robust credit card usage, and have greater difficulty paying their bills.
  • Among young adults, credit demand and default rates are relatively equal for those with and without ADHD. However, for those in middle age and beyond, the gap in default rates, poor credit scores, and reduced access to credit begins to increase.
  • Within the population of people with ADHD, the suicide risk is four times higher for those who have experienced financial distress.
  • Adults with ADHD whose credit scores identified them as high risk for default were three to four times more likely to die by suicide than individuals with poor credit who did not have ADHD.

“For some, worsening financials may contribute to psychological distress, whereas for others, psychological distress may contribute to worsening financials,” the authors wrote. “Either way, any prospective association between worsening financials and later suicide among adults with ADHD could aid in identifying those at highest risk and serve as a springboard for additional research.”

What This Means for Treatment

The knowledge that ADHD could raise a person’s risk for suicidality and/or other mental health concerns has significant implications.

For those with attention-deficit/hyperactivity and their loved ones, this underscores the seriousness with which all people should view ADHD. Anyone who continues to brush off the symptoms and behaviors of this disorder as typical adolescent rambunctiousness or nothing more than deficient self-control need to reconsider their perspective.

If someone in your life exhibits signs of ADHD, connecting them with proper treatment as soon as possible may prevent them from experiencing a host of additional problems later in life.

For treatment professionals, it is a reminder to fully assess new ADHD patients for suicidal ideation and other mental health disorders, and to be vigilant for the signs that a current patient may have developed one of these concerns.

Since experts have not yet determined if ADHD medications could increase a person’s risk for these types of negative outcomes, it is also extremely important to monitor the continued mental health of anyone who is taking any of these medications.

When a person who has developed ADHD receives appropriate care from a reputable provider, they can gain greater control of their behaviors and experience improved quality of life. Being aware of a patient’s risk for suicidality, co-occurring mental health disorders, and other potential ramifications of ADHD can keep them safe and help them make sustained progress toward a healthier future.