Attention Deficit Hyperactivity Disease (ADHD)
All people, whether they are old or young, male or female, sometimes have difficulty sitting still, paying attention, and controlling impulsive acts. But when these problems occur so often that they get in the way of day-to-day life, they may be signs of a neurodevelopmental condition called ADHD.
Attention-deficit/hyperactivity disorder (ADHD) is a common condition that causes inattention, hyperactivity/impulsivity, or both. ADHD interferes with a child’s ability to:
- Regulate activity level (hyperactivity)
- Inhibit behaviour (impulsivity)
- Attend to the task at hand (inattention)
ADHD affects many areas of a child’s functioning, including:
- Self-control of behaviour
- School achievement
- Development of social skills and positive relationships
Unless ADHD is identified and properly treated, children with ADHD are at higher risk for:
- School failure
- Depression and anxiety
- Problems with relationships
- Substance abuse
- Delinquency
- Risk for accidental injuries
- Job failure
For these reasons, it is very important to identify and treat ADHD early.
How common is ADHD?
ADHD is very common. On average, it affects 5% of school-aged children around the world, or about one in every 20 children. This means that in many countries, there may be one or two children with ADHD in every classroom.
ADHD is about three times more common in boys than in girls. However, ADHD is often easier to recognize and diagnose in boys, so the ratio of boys to girls in clinical practice is often higher still – about seven to nine boys for every girl. Girls with ADHD are more likely to be overlooked.
ADHD also affects about 4% of adults, or about one adult in 25.
ADHD is called a disorder, suggesting that people either do or do not have ADHD. In fact, though, ADHD symptoms occur on a continuum, like blood pressure. A child may have some inattentive or hyperactive symptoms without actually meeting the criteria for ADHD. Also like blood pressure, ADHD symptoms may flare up based on the situation.
These children may also be at risk for poor school outcomes such as low productivity, lower academic grades, and lower scores on standardized testing
When is ADHD usually diagnosed?
Children often start to show symptoms of ADHD in the preschool years. However, most children are not diagnosed with ADHD until they are in grade school. This is because most preschoolers are somewhat inattentive, impulsive, and highly active at times. So it may be more difficult for doctors to determine whether a preschooler’s behavior is simply at the high end of the typical range of behaviour at this age, or whether it is persistently high, impairing, and meets the diagnostic criteria for ADHD.
Once the child goes to school, doctors can find out from the teacher whether the child is inattentive, impulsive, and hyperactive at school as well as at home. Because there is no specific test that doctors can use to confirm a diagnosis of ADHD, it is important to have as much information as possible about the child’s behaviour.
Current medical knowledge about ADHD
There is still a lot we don’t know about ADHD, starting with what causes it. However, several factors seem to contribute to ADHD. Scientists believe that genes and environmental factors cause subtle brain alterations. In turn, these brain alterations cause problems with behaviour and learning.
We also know that ADHD can be treated. Over the last few decades, many studies have shown that medication and behaviour therapy are effective at treating the symptoms of ADHD.
We still do not know:
- The exact causes of ADHD
- Whether the genetic and brain differences seen in children with ADHD are a cause or an effect of ADHD
- Why some individuals with ADHD are very successful and others are not
- Why medication is effective at reducing the symptoms of ADHD
ADHD and school
Learning problems are a key feature of ADHD. Students with ADHD are at risk for:
- Low scores on schoolwork and standardized achievement tests
- Repeating a grade
- Placement in special education
- Dropping out of high school
Children with ADHD often have problems with:
- Concentration
- Working memory
- Self-regulation and staying focused on a task
- Processing speed
All these can cause problems with school work. In addition, children with ADHD often have one or more learning disabilities as well.
Medication can help with the symptoms of ADHD, but it usually does not address the other problems that can interfere with learning. Medication also cannot make up for gaps in learning that may have occurred before the child started receiving treatment. It is very important that children with ADHD get the right support at home and in school to help them reach their full potential.
We also know that ADHD can be treated. Over the last few decades, many studies have shown that medication and behaviour therapy are effective at treating the symptoms of ADHD.
We still do not know:
- The exact causes of ADHD
- Whether the genetic and brain differences seen in children with ADHD are a cause or an effect of ADHD
- Why some individuals with ADHD are very successful and others are not
- Why medication is effective at reducing the symptoms of ADHD
ADHD and college or university
Many students with ADHD do graduate from high school and enroll in college and university. These findings are encouraging; they show that many students with ADHD go on to higher education. On the other hand, college life is challenging to students with ADHD. They may continue to have social, academic, and behaviour problems.
ADHD and other conditions
ADHD rarely occurs by itself. People with ADHD often have:
- Other types of co-existing mental health problems, such as oppositional defiant behaviour, aggression, or high levels of anxiety
- Learning disabilities, such as reading disability (dyslexia) and language impairments
Diagnosing ADHD
A child’s teacher may be the first person to suspect that a child has ADHD, especially if he is hyperactive and often disrupts class. However, parents may notice signs of ADHD before the child begins school, such as problems with social skills and disruptive behaviour. Alternatively, parents may realize that their child is having problems if she does poorly at school. If you or your child’s teacher suspect your child might have ADHD, your child should be assessed by a doctor or psychologist.
ADHD is very common; it is estimated that between 5% and 12% of children have ADHD. For this reason, a doctor or psychologist will consider ADHD when they see a child who:
- is doing poorly or failing at school
- disrupts class
- cannot sit still or is hyperactive
- acts without thinking
- does not pay attention or does not seem to listen
- cannot concentrate
- daydreams
- has problems with friendships and other social relationships
- has low self-esteem
If your child has signs or symptoms that make your child’s doctor suspect your child has ADHD, she will do a thorough assessment.
ADHD is not always easy to diagnose, for several reasons:
- The symptoms of ADHD are inattention and/or hyperactivity and impulsivity, but it is normal for all children to be restless, impulsive, or inattentive sometimes.
- There is no one specific test for ADHD.
- Children behave differently in different settings and with different people.
- The symptoms of ADHD look different in different children, in boys and girls, and at different ages.
- Children with only symptoms of inattention are often overlooked.
For these reasons, the doctor will need as much information as possible from you, your child, your child’s teacher, and other caregivers.
It may take some time to figure out whether your child really has ADHD. Once the doctor knows what is happening with your child, she will sit down with you and explain the diagnosis and treatment plan.
This section discusses:
- how ADHD is diagnosed
- the symptoms of ADHD
- the subtypes of ADHD
- ADHD in girls and boys
- ADHD at different ages and stages of development
- other conditions that often affect children with ADHD (comorbidity)
- conditions that may look like ADHD, but are not