A look at adult ADHD and its comorbidities.


3 min read

Jason Brien.

The vast majority of people associate attention-deficit/hyperactivity disorder (ADHD) with children. Whilst it is true that children can be diagnosed with this condition (and so continue to experience the condition throughout adulthood), adults can be diagnosed with ADHD even without a childhood diagnosis/history. Since ADHD can be diagnosed in adults without a childhood history, researchers believe that there are two different and distinct conditions with different development trajectories. Childhood ADHD is often diagnosed AFTER a referral from teachers or parents. This is rarely the case with adult ADHD which can lead to adult ADHD being misdiagnosed as other conditions (we will explore comorbidities in a minute).

Both Childhood and adult ADHD is more recognisable in males than in females as, generally speaking, males present with externalised symptoms/behaviour and females present with internalised symptoms/behaviours. In simple terms, males will externalize in the form of ‘acting out’ whereas females internalize in the form of keeping everything inside and thus experiencing depressions, anxiety, etc. Obviously not all males externalize and not all females internalize. Whether males or females internalize or externalize their ADHD symptoms/behaviours is probably more due to social conditioning and gender role conditioning rather than ADHD itself recognising which sex it is inhabiting.

In order to understand adult ADHD within the context of its comorbidities, it is important to recognise the common symptoms underlying adult ADHD. The main features of ADHD often include difficulty paying attention, impulsiveness and restlessness with the symptoms ranging from mild to severe depending on the person. Other symptoms of ADHD can include impulsiveness, poor time management, difficulty multitasking, excessive activity, poor planning, irritability and low frustration levels, disorganization and problems prioritizing/not completing tasks, trouble coping with stress and many more. Let us now explore ADHD and its relationship to conditions such as depression, bipolar disorder and anxiety.

ADHD comorbid with depression; 

When adult ADHD is comorbid with Major Depressive Disorder (MDD – major depression) the risk of suicidal behaviours and hospitalizations increases. A person diagnosed with adult ADHD may also experience depression in response to receiving and managing their diagnosis. Additionally, medications used to manage ADHD can interfere with eating and sleep patterns which are also common symptoms associated with depression. Females are also more likely to be comorbid with MDD than males due to their internalising tendencies. Those adults diagnosed with the inattentive type of ADHD are also more likely to be comorbid with MDD.  

ADHD comorbid with bipolar disorder and other mood disorders;

Adult ADHD comorbid with MDD also increases the risk of conversion from unipolar to bipolar mood disorders. That is, rather than experiencing depression alone, the comorbid individual is at greater risk of having their depression cycle with extreme emotional highs -mania. The increased risk of suicidal behaviours and hospitalizations can mimic the increased risk of suicidal behaviours and hospitalisations characteristic of the mania present in bipolar I (ADHD is often comorbid with bipolar I rather than bipolar II). Mood changes that occur in ADHD alone are often due to external causes (break up, stress, etc) whereas the mood changes characteristic of bipolar and mood disorders is often internally induced.

ADHD comorbid with anxiety disorders; 

Some researchers suggest that ADHD and anxiety have a 25% comorbidity rate. If we were to look at commonalities in symptoms between the two, we can see that anxiety and ADHD share restlessness, difficulty concentrating and paying attention, sleeping and eating changes and trouble coping with stress. Like depression and ADHD, anxiety can occur simply in response to ADHD symptoms. For example, if you constantly made social errors due to your ADHD impulsivity, you may very well begin to develop social anxiety. Likewise, if you always have to work harder to complete tasks because you cannot concentrate properly, you may develop performance anxiety. You may also develop generalized anxiety because ADHD makes your life much more challenging and so it leads you to worry about things much more.

Researchers are unsure why ADHD is comorbid with many other mental health conditions but they believe that genetics play a role. In most cases, people who are diagnosed with any mental health condition often have a family history of that condition or others similar. Childhood ADHD can be comorbid with more conditions such as learning disorders, oppositional defiant disorder (ODD), conduct disorder (CD), reactive attachment disorder (RAD), sensory integration disorder in addition to depression, anxiety and bipolar. If we remember back to when we discussed how males are more likely to externalise their ADHD symptoms, we can see how a comorbid diagnosis of ODD,  CD and RAD can occur since these three conditions are also characterised by externalising behaviours.

Treatment for ADHD alone and comorbid often involves medication, education, psychotherapy and building stress and distress tolerance skills. It is important to remember though that if a person is prescribe stimulant medication, the medication may interfere with diagnosed or undiagnosed comorbidities. In other words, stimulant medication may exacerbate mania if they are also comorbid with bipolar. This is why it is always important to be open and honest with your prescribing doctor about any side effects of the medications you are taking. Likewise, if your ADHD is comorbid, let’s say with anxiety, you may need to develop strategies to manage the symptom of restlessness in regards to both ADHD and anxiety.

Resources

https://www.mayoclinic.org/diseases-conditions/adult-adhd/symptoms-causes/syc-20350878 

https://adhd-institute.com/burden-of-adhd/comorbidities/

https://www.verywellmind.com/adhd-and-depression-4773762

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5567978/

https://www.psychiatrictimes.com/view/comorbid-adhd-and-depression-assessment-and-treatment-strategies

https://www.healthline.com/health/adhd-and-anxiety#research

https://www.additudemag.com/bipolar-disorder-adhd-puzzle/

https://www.mentalhelp.net/adhd/and-comorbidity/