Attention-deficit hyperactivity disorder (ADHD), or hyperkinetic disorder (HKD), affects people of all ages, and ADHD prevalence rates are known to vary between children, adolescents and adults (Table)1-5
Summary of ADHD prevalence rates in different age groups
|Age group||Prevalence (%)|
|Pre-school children (Europe)||1.8–1.93,4|
|Children and adolescents (worldwide)||5.3–7.12,5|
|Adults (worldwide)||1.2–7.3 (average 3.4)1|
Can you describe the differences in presentation of the children and adults that attend your practice? | Dr Joel Young | Rochester Centre for Behavioral Medicine, Michigan, USA
Children and adolescents
Meta-regression analysis of 102 studies (>170,000 total participants) estimated that the worldwide prevalence of ADHD in children and adolescents aged ≤18 years old was 5.29%.2 A more recent meta-analysis, which focused solely on Diagnostic and Statistical Manual of Mental Disorders – 4th Edition diagnostic criteria for ADHD across 86 studies (n=163,688 participants), reported a worldwide prevalence rate of 5.9–7.1% for individuals aged <18 years.5
Limited data are available on the prevalence of ADHD in pre-school children (≤6 years of age), for example, a German study assessing 14,836 children using the Strengths and Difficulties Questionnaire (SDQ) reported that 1.8% of 3–6-year olds had symptoms of ADHD.3 Similarly, the prevalence of ADHD in 1250 Norwegian pre-school children (aged 2–6 years) assessed using the SDQ was reported to be 1.9%.4
The prevalence of ADHD in adults (n=11,422) aged 18–44 years from a range of countries in Europe, the Americas and the Middle East was 1.2–7.3% (estimated mean: 3.4%).1
Once considered to be a childhood disorder,6 ADHD is now acknowledged to persist into adulthood in ~50–66% of individuals.7-9
Adult persistence is significantly associated with retrospectively reported childhood ADHD severity, childhood symptom profile (highest persistence associated with the attentional plus impulsive/hyperactive type, lowest with the impulsive/hyperactive type), comorbid major depressive disorder, high comorbidity, paternal (but not maternal) anxiety or mood disorder, and parental antisocial personality disorder.9
Reported ADHD prevalence rates can vary due to population characteristics, methodological, environmental and cultural differences, and variability in identification and diagnostic guideline tools employed in studies.2,5,10
- Fayyad J, De Graaf R, Kessler R, et al. Cross-national prevalence and correlates of adult attention-deficit hyperactivity disorder. Br J Psychiatry 2007; 190: 402-409.
- Polanczyk G, de Lima MS, Horta BL, et al. The worldwide prevalence of ADHD: a systematic review and metaregression analysis. Am J Psychiatry 2007; 164: 942-948.
- Schlack R, Hölling H, Kurth BM, et al. The prevalence of attention-deficit/hyperactivity disorder (ADHD) among children and adolescents in Germany. Initial results from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2007; 50: 827-835.
- Wichstrøm L, Berg-Nielsen TS, Angold A, et al. Prevalence of psychiatric disorders in preschoolers. J Child Psychol Psychiatry 2012; 53: 695-705.
- Willcutt EG. The prevalence of DSM-IV attention-deficit/hyperactivity disorder: a meta-analytic review. Neurotherapeutics 2012; 9: 490-499.
- Biederman J, Mick E, Faraone SV. Age-dependent decline of symptoms of attention deficit hyperactivity disorder: impact of remission definition and symptom type. Am J Psychiatry 2000; 157: 816-818.
- Barkley RA, Fischer M, Smallish L, et al. The persistence of attention-deficit/hyperactivity disorder into young adulthood as a function of reporting source and definition of disorder. J Abnorm Psychol 2002; 111: 279-289.
- Faraone SV, Biederman J, Mick E. The age-dependent decline of attention deficit hyperactivity disorder: a meta-analysis of follow-up studies. Psychol Med 2006; 36: 159-165.
- Lara C, Fayyad J, De Graaf R, et al. Childhood predictors of adult attention-deficit/hyperactivity disorder: results from the World Health Organization World Mental Health Survey Initiative. Biol Psychiatry 2009; 65: 46-54.
- Skounti M, Philalithis A, Galanakis E. Variations in prevalence of attention deficit hyperactivity disorder worldwide. Eur J Pediatr 2007; 166: 117-123.