Around 3–5 of 100 children in Australia have attention deficit hyperactivity disorder (ADHD). But new research has shown that children who are younger than their peers at school are more likely to be on medication for ADHD.
A data analysis of more than 300,000 children aged between six and 10, undertaken at Curtis University found that those children in the last month of the school year intake "were twice as likely" to receive ADHD medication as compared to those born in the first intake month.
But rather than take this as a sign that younger children are more likely to have ADHD, the study concluded that the more likely explanation is that it is the result of a misdiagnosis due to immaturity.
According to Dr Martin Whitley, from Curtis University, "the most plausible explanation is that teachers provide the evidence for the diagnosis of ADHD, they assess the behaviour of these kids against their peers and they are mistaking age-related immaturity for a psychiatric disorder."
Most children aren't checked for ADHD until they are school aged, but it can be diagnosed from as young as four years old. However, diagnosing ADHD can be difficult. Symptoms are similar to that of anxiety, and post-traumatic stress disorder, and can co-occur with other conditions such as autism.
There is no single test to diagnose ADHD. Rather, ADHD is diagnosed after a person has regularly shown some or all of the symptoms for more than six months. And these symptoms need to be present in different settings.
To avoid a misdiagnosis, Dr Whitley suggests more flexibility towards children starting school is needed: "Allowing parents to decide when their child is ready for school could prevent misdiagnosis."
What is ADHD?
ADHD is a neurobehavioural disorder mostly diagnosed in children. Boys are twice as likely to be diagnosed with ADHD than girls; adults can develop symptoms too. ADHD makes it hard for children to sit still for long periods; they have trouble focusing and often act before they think. Overall, children have problems learning, controlling their behaviour, thinking and/or expressing their feelings.
Though many children have trouble with these things, in children with ADHD the behaviour is extreme and can have a significant impact on their lives.
There are three types of ADHD:
Combined type: Children have trouble concentrating, they are restless and always on the go.
Inattentive type: Children have trouble remembering instructions, paying attention, concentrating or finishing tasks. Symptoms include:
- Inability to pay attention
- Making a lot of 'careless' mistakes
- Struggling to follow instructions
- Struggling to finish tasks
- Being easily distracted
- Struggling to remember everyday things
- Don't seem to listen when spoken to
- Often losing things.
Hyperactive/impulsive type: Children act without thinking and have trouble slowing down. Symptoms include:
- Fidgeting, or inability to sit still
- Running and climbing in inappropriate situations
- On the go constantly
- Talking a lot
- Finding it hard to play quietly
- Struggling to stay seated at the dinner table
- Being impatient and unable to wait for their turn
- Interrupting without asking.
ADHD was first mentioned in 1902, but as yet the exact cause of the disorder is unknown.Better Health Victoria suggest contributing factors include:
- Genetics: some research suggests possible gene mutations may be present.
- Drugs: the child's mother used nicotine or cocaine during pregnancy.
- Lead: chronic exposure to low levels of lead may influence behaviour and brain chemistry.
- Lack of early attachment: if a baby does not bond with their parent or caregiver, or has traumatic experiences related to the attachment, this can contribute to their inattention and hyperactivity.
- Neurophysiology: which includes differences in brain anatomy, electrical activity and metabolism.
