It is likely that you are familiar with someone who has attention deficit hyperactivity disorder (ADHD), or you may even have it yourself. ADHD is a complex condition characterized by symptoms such as a constant inability to focus, impulsiveness, difficulty sleeping, and mood swings. Recent data from the Centers for Disease Control and Prevention shows that an estimated 7 million children in the U.S. (11.4% of all children) have been diagnosed with ADHD, along with 15.5 million U.S. adults (6% of the adult population)—half of whom were diagnosed as children.
These numbers are not static, however. The prevalence of diagnosed ADHD has been steadily increasing in the U.S. over time and varies significantly from state to state. Globally, ADHD rates tend to be lower than those in the U.S., but they have been rising in some parts of the world. The reasons for these differences in diagnosed ADHD rates, whether across states or countries, are not entirely clear.
It is possible that much of this increase simply reflects doctors becoming better at recognizing ADHD in children and adults over time. However, ADHD is also believed to be primarily caused by a complex mix of genetic and environmental factors, some of which may be on the rise. In a less supported theory, Robert F. Kennedy Jr., the Secretary of Health and Human Services, recently suggested—without evidence—that the increase in ADHD and other neurological conditions may be due to food dyes or another environmental toxin.
Some researchers argue that cultural perceptions of the behaviors associated with ADHD, particularly in children, as well as other societal factors, may contribute to differences in ADHD rates. To explore this further, we consulted psychologists, psychiatrists, and medical historians for their insights on why ADHD rates vary so widely from place to place. Their responses have been edited for clarity and grammar.
Kevin Antshel, a psychologist specializing in ADHD and other developmental conditions at Syracuse University, explains that the prevalence of ADHD in children varies between 5% and 10% depending on the region of the world. ADHD rates are generally higher in the U.S. (around 10%) and lower in Europe and Asia (around 5%). He attributes these differences to medical, social/cultural, and educational factors.
Matthew Smith, a professor of health history at the University of Strathclyde, notes that ADHD is most commonly diagnosed in the United States because it was where the condition was first recognized. American children were diagnosed with what we now know as ADHD in the late 1950s, leading to increased awareness and diagnosis of the disorder. In the 1970s, certain tactics used by drug companies were restricted, but the introduction of direct-to-consumer advertising in the 1980s and 1990s further increased the popularity of what is now known as ADHD. Alongside these factors, environmental influences such as synthetic food additives, exposure to lead, lack of exercise, and limited time spent in nature also play a role in contributing to ADHD behaviors. These factors are more prevalent in the U.S. compared to other countries.
Joel Nigg, a Professor of psychiatry and co-director at Oregon Health & Science University’s School of Medicine, highlights several factors contributing to the varying rates of ADHD diagnosis across countries. He mentions differences in laws, treatment guidelines, healthcare systems, and clinician perspectives on diagnosing ADHD as key factors. Additionally, genetic influences and environmental exposures are both important in understanding the etiology of ADHD.
Stephen Hinshaw, a Distinguished professor of psychology at the University of California, Berkeley, emphasizes that ADHD is a complex condition with no objective biological marker. He mentions the impact of ADHD on academic, social, and emotional aspects of an individual’s life. He also discusses the heritability of ADHD and how genetic predispositions, along with parenting and schooling, can influence the severity of symptoms.
International studies have shown consistent rates of diagnosed ADHD in countries with compulsory education, indicating that around 5 to 8% of young people may have difficulties with self-control. However, the U.S. and Israel have higher rates of diagnosed ADHD, which Hinshaw attributes to extreme academic pressure in these countries. He also discusses the influence of educational policies on ADHD diagnostic rates across different U.S. states. Jadi, di negara-negara yang tiba-tiba menetapkan tingkat kinerja akademik tertentu untuk mempertahankan dukungan negara bagi distrik-distrik tersebut, tingkat diagnosis ADHD naik secara tiba-tiba selama beberapa tahun berikutnya – karena tekanan untuk mengobati anak-anak tersebut dan karena kebijakan pada saat itu yang mengesampingkan anak-anak yang didiagnosis dengan ADHD dari dihitung dalam rata-rata skor ujian distrik (karena anak-anak ini sekarang merupakan anak “pendidikan khusus”). Secara keseluruhan, meskipun realitas psikobiologis ADHD, ketika dievaluasi dengan hati-hati, mungkin saja tekanan sosial dan budaya untuk “berprestasi” dapat secara salah meningkatkan tingkat diagnosis (a) ketika ada tekanan pada sekolah umum untuk menghasilkan skor ujian yang lebih baik dengan segala biaya dan (b) mengingat kecenderungan banyak profesional non-spesialis untuk memberikan diagnosis cepat dalam ketiadaan waktu dan usaha yang diperlukan untuk membuat diagnosis yang valid. Akhirnya, meskipun Anda tidak bertanya, telah terjadi pengabaian dan penolakan selama 100 tahun terhadap kemungkinan bahwa gadis dan wanita dapat “menderita” ADHD. Banyak pekerjaan di laboratorium saya telah menunjukkan bahwa ini adalah mitos: Anak laki-laki jauh lebih mungkin dua kali lipat daripada anak perempuan untuk mengembangkan ADHD, tetapi ini jauh berbeda dengan perbedaan 10:1 yang sering kali diutarakan. Gadis cenderung menunjukkan bentuk ADHD yang kurang rewel dan terang-terangan daripada anak laki-laki – dan para profesional harus mengejar standar diagnosis terbaru.