What We Currently Know About ADHD

By Jim Windell

           You would think that after more than 40 years of studying ADHD that there would be widespread agreement on various aspects of the disorder. However, as the authors of a recently published journal article point out, there are still misconceptions that abound about ADHD and that these misconceptions stigmatize affected people, reduce the credibility of providers, and prevent – and sometimes delay – treatment.

           In order to challenge misconceptions in our society, the authors, led by Stephen Faraone, with the Departments of Psychiatry and Neuroscience and Physiology, Psychiatry Research Division, SUNY Upstate Medical University, in Syracuse, New York, curated ADHD findings that had a strong evidence base.

           The authors reviewed studies with more than 2,000 participants or meta-analyses from five or more studies or 2,000 or more participants. From the literature they found, they extracted evidence-based assertions about ADHD. They then took these assertions and converted them into 208 empirically supported statements about ADHD.  The result is this article, called an International Consensus Statement on ADHD, and was published in the journal Neuroscience & Biobehavioral Reviews. The aim of the article, in addition to correcting misconceptions, was to provide current and accurate information about ADHD supported by a substantial and rigorous body of evidence.

           Here are just a sprinkling of findings from the 208 presented in the article:

            • The syndrome we now call ADHD has been described in the medical literature since 1775.

            • When made by a licensed clinician, the diagnosis of ADHD is well-defined and valid at all ages, even in the presence of other psychiatric disorders, which is common

            • ADHD is more common in males and occurs in 5.9% of youth and 2.5% of adults. It has been found in studies from Europe, Scandinavia, Australia, Asia, the Middle East, South America, and North America.

            • ADHD is rarely caused by a single genetic or environmental risk factor but most cases of ADHD are caused by the combined effects of many genetic and environmental risks each having a very small effect.

            • People with ADHD often show impaired performance on psychological tests of brain functioning, but these tests cannot be used to diagnose ADHD.

            •  ADHD can only be diagnosed by a licensed clinician who interviews the parent or caregiver and/or patient to document criteria for the disorder

           • Neuroimaging studies find small differences in the structure and functioning of the brain between people with and without ADHD. These differences cannot be used to diagnose ADHD.

           •  People with ADHD are at increased risk for obesity, asthma, allergies, diabetes mellitus, hypertension, sleep problems, psoriasis, epilepsy, sexually transmitted infections, abnormalities of the eye, immune disorders, and metabolic disorders.

           • People with ADHD are at increased risk for low quality of life, substance use disorders, accidental injuries, educational underachievement, unemployment, gambling, teenage pregnancy, difficulties socializing, delinquency, suicide, and premature death.

           •  Regulatory agencies around the world have determined that several medications are safe and effective for reducing the symptoms of ADHD as shown by randomized controlled clinical trials.

           •  Treatment with ADHD medications reduces accidental injuries, traumatic brain injury, substance abuse, cigarette smoking, educational underachievement, bone fractures, sexually transmitted infections, depression, suicide, criminal activity and teenage pregnancy.

           • The adverse effects of medications for ADHD are typically mild and can be addressed by changing the dose or the medication.

           • The stimulant medications for ADHD are more effective than non-stimulant medications but are also more likely to be diverted, misused, and abused.

          • Non-medication treatments for ADHD are less effective than medication treatments for ADHD symptoms, but are frequently useful to help problems that remain after medication has been optimized.

             To read the full article or view the hundreds of references, find it at:

Stephen V. Faraone, Tobias Banaschewski, David Coghill, Yi Zheng, Joseph Biederman, Mark A. Bellgrove, Jeffrey H. Newcorn, Martin Gignac, Nouf M. Al Saud, Iris Manor, Luis Augusto Rohde, Li Yang, Samuele Cortese, Doron Almagor, Mark A. Stein, Turki H. Albatti, Haya F. Aljoudi, Mohammed M.J. Alqahtani, Philip Asherson, Lukoye Atwoli, Sven Bölte, Jan K. Buitelaar, Cleo L. Crunelle, David Daley, Søren Dalsgaard, Manfred Döepfner, Stacey Espinet, Michael Fitzgerald, Barbara Franke, Jan Haavik, Catharina A. Hartman, Cynthia M. Hartung, Stephen P. Hinshaw, Pieter J. Hoekstra, Chris Hollis, Scott H. Kollins, J.J. Sandra Kooij, Jonna Kuntsi, Henrik Larsson, Tingyu Li, Jing Liu, Eugene Merzon, Gregory Mattingly, Paulo Mattos, Suzanne McCarthy, Amori Yee Mikami, Brooke S.G. Molina, Joel T. Nigg, Diane Purper-Ouakil, Olayinka O. Omigbodun, Guilherme V. Polanczyk, Yehuda Pollak, Alison S. Poulton, Ravi Philip Rajkumar, Andrew Reding, Andreas Reif, Katya Rubia, Julia Rucklidge, Marcel Romanos, J. Antoni Ramos-Quiroga, Arnt Schellekens, Anouk Scheres, Renata Schoeman, Julie B. Schweitzer, Henal Shah, Mary V. Solanto, Edmund Sonuga-Barke, César Soutullo, Hans-Christoph Steinhausen, James M. Swanson, Anita Thapar, Gail Tripp, Geurt van de Glind, Wim van den Brink, Saskia Van der Oord, Andre Venter, Benedetto Vitiello, Susanne Walitza, & Yufeng Wang. (2021). The World Federation of ADHD International Consensus Statement: 208 Evidence-based Conclusions about the Disorder. Neuroscience & Biobehavioral Reviews.

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