Attention-deficit hyperactivity disorder overview
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Charmaine Patel, M.D. [2], Haleigh Williams, B.S.
|
Attention-deficit hyperactivity disorder Microchapters |
|
Differentiating Attention-Deficit Hyperactivity Disorder from other Diseases |
|---|
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
Template:Attention-deficit hyperactivity disorder On the Web |
|
American Roentgen Ray Society Images of Attention-deficit hyperactivity disorder overview |
|
Attention-deficit hyperactivity disorder overview in the news |
|
Directions to Hospitals Treating Attention-deficit hyperactivity disorder |
|
Risk calculators and risk factors for Attention-deficit hyperactivity disorder overview |
Overview
- Attention-deficit hyperactivity disorder (ADHD) is a neurobehavioral brain disorder marked by an ongoing pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. It may negatively impact the patient’s academic or professional performance and/or social interactions.
- ADHD has a strong component of heritability.
- ADHD is more commonly diagnosed in boys than in girls, though this may be because the symptoms of the disorder are less easily recognized in girls.[1]
Historical Perspective
- ADHD symptoms have been recognized in children and described in medical texts since the nineteenth century, though the formal diagnosis had not yet been devised.
- ADHD was first included in some form in the DSM in its second edition, when it was referred to as “hyperkinetic reaction of childhood.” It was not until the third edition of the DSM was released in 1980 that the disorder was formally identified as “ADD (Attention-Deficit Disorder) with or without hyperactivity.”[2]
- Rhode Island physician Dr. Charles Bradley pioneered the use of medications to treat ADHD in 1937. Since that time, the prescription of stimulants has become a first-line treatment for ADHD.[3]
Classification
ADHD may be classified according to the DSM-V criteria into three subgroups:
- predominantly inattentive type;
- predominantly hyperactive-impulsive type; and
- combined type.[4]
Pathophysiology
- ADHD appears to be highly heritable, although one-fifth of all cases are estimated to be caused by trauma or exposure to toxins.
- Evidence suggests that ADHD is a heterogeneous disorder, meaning that several causes could create very similar symptomology.[5]
- Although there is evidence for dopamine abnormalities in ADHD, it is not clear whether abnormalities of the dopamine system are a molecular abnormality of ADHD or a secondary consequence of ADHD.
Causes
There are no established causes of ADHD. Studies suggest that ADHD results from a complex interaction between genetic and environmental factors.[6]
Differentiating Attention Deficit Hyperactivity Disorder from other Diseases
- ADHD must be differentiated from other diseases that cause behavioral issues and anxiety such as anxiety disorder, dissociative disorder, conduct disorder, and oppositional defiant disorder.
- ADHD must also be differentiated from the other psychiatric disorders with which it shares common genetic roots, including autism, bipolar disorder, major depression, and schizophrenia.[7]
Epidemiology and Demographics
- The prevalence of attention-deficit hyperactivity disorder (ADHD) is estimated to be 5,000 per 100,000 (5%) children and 2,500 per 100,000 (2.5%) adults.[4]
- Boys are more commonly affected by ADHD than girls. The male to female ratio is 2 to 1.[8]
Risk Factors
Several factors have been implicated as risk factors in the development of ADHD. Maternal smoking and alcohol use have had an association to the development of ADHD in the child. In addition, high blood lead levels have been linked to ADHD.
Natural History, Complications and Prognosis
ADHD is currently considered to be a persistent and chronic condition for which no medical cure is available. ADHD is most commonly diagnosed in children and, over the past decade, has been increasingly diagnosed in adults. About 60% of children diagnosed with ADHD retain the condition as adults.[9] Adults are able to hide the symptoms more easily. Children who are not medicated for ADHD have higher rates of substance abuse in adulthood. Paradoxically, stimulant medications are intoxicants, and substance dependence may develop.
Diagnosis
History and Symptoms
Diagnosis of ADHD is based on DSM IV criteria. These are very specific criteria which assess the patient's functioning and the impact of their symptoms on their life, in various settings. History includes symptoms of innattentiveness, hyperactivity, impulsivity, difficulty functioning at school and at an occupational level, and difficulty with organization. Symptoms may also affect relationships in the social setting.
Treatment
Medical Therapy
First line treatments include stimulant medications such as methyphenidate and dextroamphetamine. More recent, less addictive medications used is modafinil. Behavioral modification and strategies have also been shown to help, as pharmacologic treatment is thought to mostly help symptoms associated with poor concentration. Methods of treatment usually involve some combination of medications, behavior modifications, life style changes, and counseling.
References
- ↑ National Institute of Mental Health (NIH). (2016). "Attention Deficit Hyperactivity Disorder."
- ↑ Lange, K. W., Reichl, S., Lange, K. M., Tucha, L., & Tucha, O. (2010). The history of attention deficit hyperactivity disorder. Attention Deficit and Hyperactivity Disorders, 2(4), 241–255. http://doi.org/10.1007/s12402-010-0045-8.
- ↑ Strohl, M. P. (2011). Bradley’s Benzedrine Studies on Children with Behavioral Disorders. The Yale Journal of Biology and Medicine, 84(1), 27–33.
- ↑ 4.0 4.1 Diagnostic and statistical manual of mental disorders : DSM-5. Washington, D.C: American Psychiatric Association. 2013. ISBN 0890425558.
- ↑ Barkley, Russel A. "Attention-Deficit/Hyperactivity Disorder: Nature, Course, Outcomes, and Comorbidity". Retrieved 2006-06-26.
- ↑ OurMed. (2010). "Attention-deficit hyperactivity disorder."
- ↑ Cross-Disorder Group of the Psychiatric Genomics Consortium. (2013). Identification of risk loci with shared effects on five major psychiatric disorders: a genome-wide analysis. Lancet, 381(9875), 1371–1379. http://doi.org/10.1016/S0140-6736(12)62129-1.
- ↑ Briars, L., & Todd, T. (2016). A Review of Pharmacological Management of Attention-Deficit/Hyperactivity Disorder. The Journal of Pediatric Pharmacology and Therapeutics : JPPT, 21(3), 192–206. http://doi.org/10.5863/1551-6776-21.3.192.
- ↑ Attention-Deficit / Hyperactivity Disorder: ADHD in Adults. WebMd.com. Retrieved on December 11, 2006.