ADHD and Depression: What's the link?

What is ADHD?

Attention deficit/hyperactivity disorder (ADHD) is a condition that affects behavior and concentration. Symptoms of ADHD can relate to inattention, hyperactivity, and impulsiveness.

ADHD often emerges in childhood and can cause issues with functioning at school, at home, and with social abilities. In many cases, it can continue into adulthood, although symptoms can improve with age for some people ^[1].

What is depression?

Depression is a mental health condition that impacts mood, thoughts, and behavior. Depression can cause physical and emotional symptoms that can severely impact functioning in various aspects of life.

Depression can emerge at any age, although it is often diagnosed in young adults. It can be a lifelong condition, although the severity of symptoms can fluctuate ^[2].

When symptoms overlap

Symptoms of ADHD and depression can vary from person to person. Typically, symptoms of ADHD include ^[1]:

• Becoming easily distracted
• Having difficulty focusing on or completing tasks
• Making mistakes with work
• Forgetting or losing things
• Inability to focus on or carry out verbal instructions
• Quick and regular changes in focus and activity
• Feeling unable to sit still
• Constantly moving, such as pacing or fidgeting
• Talking a lot
• Interrupting other people or speaking at inappropriate times
• Impatience and inability to wait
• Difficulty concentrating
• Behaving recklessly or inappropriately
• Getting easily frustrated or experiencing mood swings

Symptoms of depression typically include ^[2]:

• Feeling very sad or empty
• Feelings of hopelessness, guilt, worthlessness
• Feeling irritable, restless, frustrated
• Low self-esteem
• No pleasure or interest in previously enjoyable activities
• Lack of motivation or energy
• Issues with sleep, such as insomnia or sleeping too much
• Difficulty with concentration and memory
• Changes in appetite
• Headaches, stomachaches, back or muscle pain
• Thoughts of self-harm or suicide
• Impairments in self-care and hygiene

Various symptoms of ADHD and depression can appear similar. This can complicate diagnosis or cause one condition to go unnoticed in those with ADHD and depression ^[3].

Overlapping or similar symptoms of ADHD and depression include ^[3][4][5]:

• Low mood and self-esteem: Mood changes are a core symptom of depression but can also occur in ADHD. Often, symptoms of ADHD can cause several issues with functioning, potentially leading to poor self-esteem, demoralization, and feelings of worthlessness and incompetence. Also, people with ADHD may become low in mood when they feel unstimulated or bored.
• Sleep problems: Both ADHD and depression can cause issues around sleep, particularly difficulties falling asleep and feeling rested.
• Loss of interest: Commonly, people with depression experience anhedonia, causing them to lose interest in activities or hobbies they previously enjoyed. People with ADHD often lose interest in activities, becoming distracted or needing to move on to another activity.
• Restlessness: Restlessness can occur in people with ADHD or depression. This can present as fidgeting, pacing, or leg and hand movements or twitches.
• Problems with concentration: Difficulty focusing on tasks or activities is a common symptom of both ADHD and depression. This can cause impairments in functioning in various life aspects.

ADHD vs. depression: Causes

Causes of ADHD and depression that are similar include ^[1][2][6]:

• Genetics: ADHD and depression are believed to both have genetic factors related to their development. The prevalence of both conditions is higher in people with a family history. Some research suggests that the same congenital abnormalities may occur within both conditions, perhaps explaining the similarities in symptoms.
• Neurobiology: Both ADHD and depression are found to be linked to abnormalities in the brain. This includes reduced volumes of certain areas and altered levels of various neurotransmitters.

Other causes or contributing risk factors of ADHD include ^[1]:

• Pregnancy complications, such as premature birth, low birth weight, and exposure to alcohol during pregnancy
• Epilepsy
• Brain damage, whether from birth complications or incurred later in life

Other causes or contributing risk factors of depression include ^[2]:

• Childhood adversity, such as trauma, abuse, or bullying
• Life stressors or changes, such as divorce, housing issues, financial difficulties, and loss of a loved one
• Use of illicit substances or medications
• Physical illness

Does ADHD cause depression?

Often, people with either ADHD or depression experience a comorbid condition. It is common for ADHD and depression to occur together. Research suggests that around 40% of children with ADHD also experience symptoms of depression ^[4][7]. Furthermore, it is thought that approximately 70% of people with ADHD receive treatment for depression at some point during their lifetime ^[3].

Children with ADHD may develop symptoms of depression due to the consequences of ADHD symptoms. For example, it is common for children with ADHD to underperform academically, be told off by their parents or teachers for disruptive behavior, or experience difficulties with friendships. This could lead to feelings of guilt, shame, worthlessness, or unhappiness ^[6][7].  

Similarly, if ADHD continues to impact functioning into adulthood, people may experience similar difficulties with relationships or work. This could further contribute to negative emotions and feeling hopeless and worthless. Experiencing these negative emotions and thoughts for a prolonged period can increase vulnerability to depression ^[5].

As such, it is likely that ADHD significantly contributes to or exacerbates symptoms of depression. This is demonstrated by a much higher prevalence of depression among people with ADHD than the general population. Research also indicates that ADHD is linked to an earlier age of depression onset, more severe symptoms, and increased suicidal ideation and attempts ^[5][7][8].

Similarly, it is believed that depression can also worsen symptoms of ADHD. Therefore, people who experience both ADHD and depression are likely to experience more severe symptoms than people with one of these conditions. This can worsen outcomes and make treatment more challenging ^[4][5].

Treatment for combined ADHD and depression

Treatment for people with both ADHD and depression may be more challenging than for either condition alone. The symptoms of both can be more severe, and it may be likely for other conditions also to be present ^[4][5].

As both ADHD and depression can present differently from person to person, the best treatment will depend on the individual and their symptoms. In many cases, ADHD symptoms contribute to depression symptoms such as worsening mood and functioning. Therefore, treating symptoms of ADHD could also improve or prevent depression symptoms ^[7].

Therapy

Several types of therapy can help treat ADHD and depression, including ^{[1][2][3][4][5]}:

• Psychotherapy: Talk therapy can be helpful for people to exploretheir emotions and discuss any challenges they face due to their symptoms. This can help reduce emotional distress and provide a better understanding of the two conditions.
• Cognitive behavioral therapy (CBT): CBT is a specialized type of psychotherapy in which individuals can learn to alter harmful thoughts and behaviors while learning new positive coping strategies. This has been found to be effective for people with depression and people with both depression and ADHD.
• Family therapy: Attending therapy with parents and other family members can be helpful for children and adolescents. This can help the family learn how to understand and manage symptoms and utilize healthy and constructive communication in the home.
• Mindfulness therapy: Mindfulness has been found to be effective at reducing negative emotions and stress in people with depression and ADHD. It can help to reduce impulsivity and frustration, providing tools for managing symptoms of both conditions.

Medication

Commonly, ADHD is treated with stimulants, such as methylphenidate. These medications can be effective at managing symptoms of ADHD. However, for some people, they can cause a worsening in mood ^[1][4].

Commonly, depression is treated with antidepressant medications, such as selective serotonin reuptake inhibitors (SSRIs), including fluoxetine, sertraline, or citalopram. These medications can be very effective for some people with ADHD and depression, but for some, they can cause a significant worsening in suicidal ideation ^[2][4].

Treating combined ADHD and depression with medication must be considered with caution and on an individualized basis. Medication that may help one condition could worsen the other. As such, it is often best practice to utilize one type of medication and to wait before adding further medications to treatment, closely monitoring any changes in physical or mental well-being ^[4].

If medication is to be used, treating the more severe condition first is vital. For example, if someone is experiencing severe symptoms of depression, such as recurrent suicide attempts and self-harm, it is essential to treat these symptoms first. Likewise, if ADHD symptoms are the most prevalent and problematic, these must be managed before adding other treatments ^[3][4].

Then, if it is required, additional medications may be introduced gradually. It can be safe and effective to combine a stimulant and antidepressant medication if prescribed appropriately ^[4][9].