It is not uncommon in my medical practice to hear patients say, “Back in my day, we didn’t have all this ADHD stuff.” But how common is Attention Deficit Hyperactive Disorder (ADHD)? The fact is that ADHD (formerly known as ADD) is the most common neurodevelopmental disorder among children in North America. As a physician, I am often left wondering if ADHD is increasing, or if we are just able to better detect it?
Why is the diagnosis of ADHD important?
ADHD serves as an important diagnosis for children because undiagnosed ADHD can interfere with a child’s ability to participate in school, home, or play activities.
Compared to children without ADHD, children with ADHD are at greater risk of:
- Self-injury: Children with ADHD are more likely to engage in intentional, or unintentional self harm. This can include things like burning themselves or cutting themselves.
- Car Crashes: Are almost twice as likely to have motor vehicle accidents when they begin to drive.
- Worse School Performance: Children with ADHD are more likely to drop out of school, have lower academic achievement scores, and fail more courses. This impairment persists even if the child no longer meets criteria for an ADHD diagnosis into adolescence or adulthood.
- Less likely to go to university: Data shows only 15-19% of adolescents with ADHD complete a bachelor’s degree, compared to 50-64% of adolescents without ADHD.
- Drug use: Children with ADHD are over 2.5 times more likely to use substances in adolescence and adulthood. The risk of specific substances includes:
- Nicotine: 2.1 times higher risk
- Alcohol: 1.7 times higher risk
- Marijuana: 2.8 times higher risk
- Cocaine: 2.1 times higher risk
So just how common is ADHD?
One study by the U.S. Health Statistics Reports showed that there was an increase in the rates of ADHD between the years of 1997-1999, and 2006-2008. This study caused some heightened concerns that the rates of ADHD were increasing. On later review of this study, it was found there was a flaw in both school and parent reporting.
The United States Vital Health Statistics reported that approximately 9.5% of all American children between 6 to 17 years old will receive an ADHD diagnosis. Other studies have shown rates anywhere from 3 to 8%. Based on my research, it appears that there is a wide difference in rates of ADHD across different studies.
Ultimately it is unclear if the prevalence of ADHD is increasing or if we are just getting better at detecting it. So how common is ADHD?
Based on my research it is about 1 in 10 children, or 2 to 4 children on average per classroom.
If you think your child may have ADHD, consider taking them to your family doctor or pediatrician for a check-up.
My initial suspicion was that diagnosis of ADHD appears to be increasing due to a number of factors. The first is that North Americans have become more willing to discuss mental illness and mental health. As a population whole, we are now more forthcoming about our mental health struggles such as ADHD. The second reason is that mental health services have improved and hopefully fewer children with ADHD are going undiagnosed.
I want to emphasize the importance of taking your child to the doctor if you feel like they are struggling at school, work, or while playing with other children. Treatment of ADHD may reduce some of the risks described above.
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