Child Development

Is ADHD Genetic? Causes, Risk Factors, and More

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Attention deficit disorder (ADHD) is a condition that affects a person’s self-control, and ability to focus and sit still. Researchers have been studying the causes of ADHD, and studies have supported that genetics play a role in the cause of the condition. In this article, I’ll outline ADHD and genetics, its causes and risk factors, and how ADHD impacts the brain. We’ll also discuss symptoms, diagnosis, and treatment.

Is ADHD Genetic?

There is evidence that suggests that ADHD is genetic, and can be passed down from parent to child. A person who has parents or siblings with ADHD is at a higher risk of developing symptoms of ADHD. It’s still unclear to researchers which genes make a person more susceptible to developing ADHD, and there is no genetic test that can determine if you will or won’t have ADHD. 

Since ADHD is a complex condition, it seems that the condition affects at least two genes. Research shows the connection between ADHD and the neurotransmitter, dopamine, so it’s possible that genes affecting the production of dopamine are related. However, genetics is not the only cause of ADHD, as environmental factors and lifestyle during pregnancy may also cause ADHD.

Causes and Risk Factors of ADHD

Along with genetics, there are other potential causes and risk factors of ADHD, such as: 

  • Brain injury: A study involving 187 children found that 62% of children who sustained a traumatic brain injury developed ADHD, compared to 15% of those who did not sustain a brain injury. While this risk factor is still being examined, researchers have posed this as a potential risk for developing the condition.
  • Exposure to environmental risks (e.g., lead) during pregnancy or at a young age: Lead is one of the most dangerous environmental pollutants. A study has discovered the connection between lead exposure and one of the types of ADHD. However, more research is to be conducted into this cause.
  • Alcohol and tobacco use during pregnancy: Alcohol and tobacco use during pregnancy may be a risk for a child developing ADHD, and it’s advised for mothers to avoid alcohol and tobacco during pregnancy, due to the additional possible medical risks.
  • Premature delivery: Premature delivery occurs when a baby is born before 37 weeks of pregnancy. Researchers have found that being born early was associated with an increased risk of ADHD.
  • Low birth weight: Low birth weight is a term used to describe babies weighing less than 5 pounds when born. A study found a correlation between low birth weight and developing ADHD once they reach childhood.

How ADHD Impacts the Brain

There are significant differences when compared to neurotypical brains. Neuro-imaging research has shown that the brains of children with ADHD mature more slowly compared to those of children without the condition. 

It’s also shown that certain brain regions of those with ADHD are smaller in size, particularly the frontal cortex, which is responsible for executive functioning. However, this difference is not significant enough to make an ADHD diagnosis

Other Differences in the Brain

Size is not the only factor that affects the brain of people with ADHD. There are also chemical differences that have been researched and observed. Dopamine is a neurotransmitter that allows emotional regulation, feelings of pleasure, and reward. Research has shown that people with ADHD have lower levels of dopamine when compared to those without the condition.

Symptoms

Symptoms of ADHD can vary from person to person, and some people may have fewer ADHD symptoms as they age. Symptoms in adults look different than they do in children.

Children

In children, ADHD symptoms may include:

Inattention

  • Failure to pay close attention to details or make careless mistakes in schoolwork
  • Having trouble staying focused on tasks or play
  • Appearing not to listen, even when spoken to directly
  • Difficulty following through on instructions and fail to finish schoolwork or chores
  • Trouble organizing tasks and activities
  • Avoiding or disliking tasks that require focused mental effort, such as homework
  • Losing items needed for tasks or activities, for example, toys, school assignments, pencils
  • Being easily distracted
  • Forgetting to do some daily activities, such as forgetting to do chores

Hyperactivity and impulsivity

  • Fidgeting with or tapping their hands or feet, or squirming in the seat
  • Having difficulty staying seated in the classroom or in other situations
  • Being on the go, in constant motion
  • Running around or climbing in situations when it's not appropriate
  • Having trouble playing or doing an activity quietly
  • Talking too much
  • Blurting out answers, interrupting
  • Having difficulty waiting for their turn
  • Interrupting or intruding on others' conversations, games, or activities

Adults

In adults, ADHD symptoms may include:

  • Impulsiveness
  • Disorganization and problems prioritizing
  • Poor time management skills
  • Difficulty focusing on tasks
  • Trouble multitasking
  • Excessive activity or restlessness
  • Difficulty following through and completing tasks
  • Hot temper
  • Trouble coping with stress
  • Poor planning
  • Low frustration tolerance
  • Frequent mood swings

Diagnosis

If you think you or your child may have ADHD, it’s important to talk to your healthcare provider so they can take the proper steps for diagnosis.

Your provider will likely ask questions about:

  • Your symptoms or those of your child
  • When symptoms began
  • Where the symptoms occur – for example, at home, in school, college or university, or at work
  • If the symptoms affect your or your child's day-to-day life – for example, if they make socializing difficult
  • Any recent significant events in your or your child's life, such as a death or divorce in the family
  • Any family history of ADHD
  • Any other problems or symptoms of different health conditions you or your child may have

Children and teenagers must have six or more symptoms of inattentiveness, and/or hyperactitivity/impulsivity to be diagnosed with ADHD. 

While this can vary, an adult may be diagnosed with ADHD if they have 5 or more of the symptoms of inattentiveness, or 5 or more of hyperactivity and impulsiveness, listed in the diagnostic criteria for children with ADHD.

Treatment

There are various treatment options for ADHD, and they can be different between children and adults.

Children

The following are treatment options for children. 

  • Medications: Stimulant medications such as Amphetamines and Methylphenidates support the brain in stimulating brain chemicals known as neurotransmitters. The right dose may be able to help ADHD symptoms in children, but it’s important to consult a healthcare professional.
  • Behavior therapy: Behavior therapy is usually provided by a psychologist, therapist, social worker, or other mental health professional. This is used to teach the child and parent about behavior-changing strategies and dealing with hard situations. 
  • Lifestyle changes: While this is not necessarily a treatment for ADHD, lifestyle changes can help support a child with ADHD and help improve their self-esteem. Some lifestyle changes to take into account are identifying difficult situations, recognizing your child’s strengths, and keeping a regular schedule.

Adults

The following are treatment options for adults with ADHD.

  • Medications: Stimulants, along with other medications, are used to treat adults with ADHD. These medications can support the balance of neurotransmitters in the brain, and reduce symptoms.
  • Psychological counseling: Psychological counseling can help an adult with ADHD manage their symptoms, such as reducing impulsivity or coping with failure. Cognitive-behavioral therapy (CBT) is a type of psychological counseling that may help change negative thought patterns into positive ones.
  • Lifestyle changes: Lifestyle changes, such as sticking to a routine, or breaking down tasks, may support adults with ADHD manage their symptoms.

Frequently Asked Questions (FAQs)

Below I outline frequently asked questions when it comes to ADHD.

Can you have ADHD if no one in your family has it?

While there is research that supports that ADHD is genetic, it’s still possible to have ADHD even if no one in your family has it. 

Can you outgrow ADHD?

Most children diagnosed with ADHD will not outgrow the condition. It’s a myth that most children grow out of ADHD. However, with proper treatment, some people have fewer symptoms as they grow older. Symptoms may also change over time. 

Takeaway

Research supports that ADHD is genetic, but it’s not the only factor that influences whether or not someone will develop the condition. Other factors, such as brain injury, exposure to environmental risks, and low birth weight may contribute as well.