The prevalence of ADHD among adults in The Netherlands between the ages of 18 and 75 is estimated to be between 1.5% and 2.5%, with no indication of a decline as people get older.
The highest rates emerged from Africa (8.5%) and South America (11.8%). Corroboration comes from a dimensional ADHD scale used in 21 countries. Japanese and Finnish children scored lowest, Jamaican and Thai children scored highest, and American children scored about average (7).
The prevalence rates of ADHD in children and adolescents are high with estimates of 5.3 % [45] to 5.9 % [59] worldwide and 4.6 % for Europe [45].
Researchers at Oregon Health & Science University estimate the true percentage of people with Attention-Deficit/Hyperactivity Disorder, or ADHD, in the United States is approximately 3.5% of the population — substantially lower than many common estimates.
Results: The literature search generated 9,105 records, and 303 full-text articles were reviewed. One hundred and two studies comprising 171,756 subjects from all world regions were included. The ADHD/HD worldwide-pooled prevalence was 5.29%. This estimate was associated with significant variability.
In Australia, ADHD is one of the most common neurodevelopmental disorders, affecting 6-7% of the population4. Even into adulthood, around 65% of those diagnosed continue to experience symptoms, with 15% still meeting the criteria for a diagnosis of ADHD5.
It's estimated one in 20 children in Australia have ADHD. It is more common in boys than girls.
According to new research published in JAMA Pediatrics, cases of attention-deficit/hyperactivity disorder, or ADHD, have increased over the past 20 years. However, the increase may be due to increased awareness, especially in the ways ADHD presents differently in boys and girls.
Approximately 6.8% (366.3 million) adults worldwide have symptomatic ADHD, which includes individuals diagnosed with ADHD regardless of the onset age.
There has been a notable increase of ADHD diagnoses in adults. ADHD symptoms persist into adulthood for as many as 60 percent of patients diagnosed while adolescents. Adult ADHD patients may struggle to focus, organize, manage time, prioritize tasks, and make decisions.
The terms 'hyperkinetic disorder' (HKD) and 'deficits in attention, motor control and perception' (DAMP) are still in use in the UK and a few other European countries (HKD) and Scandinavia (DAMP). (HKD defines a subset of patients with a particularly severe form of ADHD.)
In the UK, prevalence of ADHD in adults is estimated at 3% to 4%, with a male to female ratio of approximately 3 to 1.
ADHD facts
In the UK it's thought that between 2% to 5% of school aged children have ADHD. The prevalence of ADHD in the adult population is between 3% and 4% but the majority of these individuals are undiagnosed.
While the prevalence rates are increasingly similar by gender, the diagnosis rate among American men is nearly 69% higher than it is among American women (5.4% of men in the U.S. have an ADHD diagnosis vs. just 3.2% of women.1)
Findings. This cohort study of 238 011 children examined the association between race/ethnicity and the diagnosis of ADHD. Asian, Black, and Hispanic children were significantly less likely to be diagnosed with ADHD compared with White children.
Rather, the rise seems to be due to an increase in access to healthcare; a decrease in stigmatization about receiving mental health care; and greater awareness of the symptoms of ADHD among clinicians, guardians, educators, and patients. In the past, ADHD was only diagnosed in children who were hyperactive.
Autism is very distinct from ADHD, but the core symptoms of ADHD-Combined type, i.e., attention deficit, impulsivity, and hyperactivity, would appear to also be features of autism. ASD and ADHD are neurobiological disorders characterized by similar underlying neuropsychological “deficits”.
Similar to the hyperactive symptoms, impulsive symptoms are typically seen by the time a child is four years old and increase during the next three to four years to peak in severity when the child is seven to eight years of age.
Findings. In this systematic scoping review of 334 published studies in children and adolescents, convincing evidence was found that ADHD is overdiagnosed in children and adolescents. For individuals with milder symptoms in particular, the harms associated with an ADHD diagnosis may often outweigh the benefits.
ADHD is also three times more common in males than females, and subtypes tend to have a different prevalence. Due to this discrepancy in the prevalence of ADHD among males and females, researchers have undertaken studies to explore the sex differences in ADHD and the possible cause of the discrepancy.
ADHD Assessment & Treatment Centres
To legally protect the rights of people with ADHD in Australia, under the Disability Discrimination Act 1992 (DDA), a person's ADHD must be classed as a disability according to the criteria as specified in the DDA. DDA disability definition criteria relevant to people with ADHD: 1.
an estimated 1 in 4 (26% or 671,100) experienced at least 1 mental disorder in the preceding 12 months. anxiety disorders were the most commonly reported disorder for all young people overall (15%) followed by substance use disorders (13%) and affective disorders (6%).
The peak age of diagnosis of ADHD is in primary school children aged 5–10 years. These children typically present with poor concentration that affects their learning. A child who is unable to concentrate for long may become bored and disruptive.