Attention deficit disorder

Attention-deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed mental disorders among children, and may be diagnosed in adults, where it is often referred to as Adult attention-deficit disorder (AADD) if symptoms were not present in childhood. Current theory holds that approximately 30% of children diagnosed retain the disorder as adults.

ADHD psychosis (or ADD psychosis), on the other hand, is a distinctive form of psychosis, identified by Leopold Bellak and his colleagues, which co-occurs with attention-deficit hyperactivity disorder and tends to be treatable with typical ADHD medication such as stimulants (or some antidepressants), but not with conventional or atypical antipsychotic medication.

Contents 1 Official Definitions of ADHD 2 Cause 3 Controversy 3.1 Skepticism towards ADHD as a diagnosis 3.2 ADD/ADHD a hoax? 4 Symptoms 5 Incidence 6 Psychological testing for ADHD 6.1 Other forms of testing 7 Treatment 7.1 Mainstream treatments 7.2 Alternative treatments 7.2.1 Feingold diet 7.2.2 Vitamin B6 7.2.3 Neurofeedback 8 Possible causes 8.1 Neuro-chemical imbalance 8.2 Smoking during pregnancy 8.3 Deficiencies in nutrition 8.4 Sleep apnea 8.5 Head injuries 9 Evidence for ADHD as an organic phenomenon 10 Positive aspects 11 Adults 12 See also 13 References

Official Definitions of ADHD

The official definitions of ADHD according to the US Surgeon General and ICD-9-CM (International Classification of Disease Revised Edition 2005) is a neurological deficit classified as "metabolic encephalopathy" affecting the release and homeostasis of neurological chemicals and the functioning of the limbic system.

The official definition of ADHD found in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders-IV (Text Revision) (DSM-IV-TR), defines three subtypes of ADHD:

• Predominantly Inattentive,
• Predominantly Hyperactive-Impulsive, and
• Combined Type.

Although most diagnoses of ADHD are made for children, the DSM definitions of ADHD do not confine the disorder solely to childhood and in fact many adults are also diagnosed. Current theory holds that approximately 30% of children diagnosed retain the disorder as adults. Although the disorder may not have been diagnosed in an individual during childhood, it is also currently thought that all adults with Adult attention-deficit disorder (AADD) had it in childhood. Hyperactivity and other symptoms may be less noticeable in adults with ADD/ADHD who have learned better coping skills and other forms of adaptive behavior than they had as children. Particularly in adults, studies have shown a high correlation between ADHD and creativity.

Cause

The exact cause(s) of ADHD are not conclusively known. Scientific evidence suggests most strongly that, in many cases, the disorder is genetically transmitted and is caused by an imbalance or deficiency in certain chemicals that regulate the efficiency with which the brain controls behavior.

A 1990 study at the US National Institute of Mental Health correlated ADHD with a series of metabolic abnormalities in the brain, providing further evidence that ADHD is a neurological disorder. While heredity] is often indicated, some believe that problems in prenatal development, birth complications, or later neurological damage may contribute to ADHD, although no satifactory proof exists for this.

Causes under investigation include, but are not limited to:

• Brain differences: Brain scan technology has revealed differences in the size, symmetry, metabolism, and chemistry of the brain in those who have ADHD; however, it should be noted that there is yet no clear determination of the source of these differences.

• Genetic factors: It has been demonstrated that children who have at least one parent diagnosed with ADHD are more likely to be diagnosed as having ADHD themselves. Current research is examining which genes may be involved in ADHD. This investigative path also suggests an associated hypothesis that environmental factors, handed down from generation to generation, may trigger the symptoms associated with ADHD.

• Brain development in utero and during the first year of life, possibly related to drug use during pregnancy or environmental toxins, again, little proof seems to exist as yet.

• Environmental/dietary factors: It has also been suggested that ADHD may result from a poor diet and other external factors rather than from any physiological source. While this evidence is only anecdotal, it has been noticed that some children with ADHD seem to be addicted to milk. It has been proposed by Norwegian and British scientists that this is due to the casomorphins, peptides formed by incomplete digestion of the whey protein.

Controversy

While ADD/ADHD is a known psychiatric condition, there are various theories about the cause and some controversy over the number of persons diagnosed and the cost of medications.

Skepticism towards ADHD as a diagnosis

Critics have complained that the ADHD diagnostic criteria are sufficiently general or vague to allow virtually any child with persistent unwanted behaviors to be classified as having ADHD of one type or another.

A growing number of critics have wondered why the number of children diagnosed with ADHD in the U.S. and UK has grown so dramatically over a short period of time. However, doctors point out that improving methods of diagnosis and greater awareness are probably in part, if not mostly the reason for this increase.

It has often been suggested that the causes of the apparent ADHD epidemic lie in cultural patterns that variously encourage or sanction the use of drugs as a simple and expeditious cure for complex problems that may stem primarily from social and environmental triggers rather than any innate disorder. Some critics assert that many children are diagnosed with ADHD and put on drugs as a substitute for parental attention, whereas many parents of ADHD children assert that the associated demand for attention goes beyond what can be humanly provided, causing massive disruption to other individuals and relationships, as well as to environments with dysfunctionally structured relationships such as are manifest in many classrooms. This criticism also includes the use of prescription drugs as a substitute for parental duties such as communication and supervision.

ADD/ADHD a hoax?

There are some claims that ADD/ADHD is simply a hoax. Many of these charges are that there has been a conspiracy between medical and counseling professionals and the pharmaceutical companies, or that the former have been misled by the latter, which have profited greatly from the sale of medication such as Ritalin and Adderall, and have advertised their products extensively. Since medications became available, there has been an increased number of persons diagnosed. This might be explained by increased awareness or easy solution for doctors, in any case, it seems unlikely that a Pharmaceutical company would fabricate an entire disorder, especially at the risk of millions of potential lawsuitsa if they were found out. Another explanation comes from a common misconception of the symptoms that leads to an incorrect diagnosis. For example, an employee of a school may spur the thoughts that a child has ADD simply because the child cannot be controlled in the classroom. A teacher may think a student they cannot control has ADD, but in reality the true problem is simply a lack of discipline. The same teacher won't notice the kid who forgets their papers, stares (entranced) at the carpet for long periods of time, or shows many of the true symptoms.

However, the results achieved in clinical tests with such medication and anecdotal evidence of parents, teachers, and both child and adult sufferers has been taken as proof that there is both a condition and successful treatment options for most people who meet the criteria for a diagnosis. The problem then lies in misdiagnosis; critics believe many of those being treated for ADHD do not suffer from the disorder to such a point that potentially mind-altering drugs should be prescribed.

A further problem is that ADD and ADHD are syndromes, associations of symptoms. There is no well established cause for the condition. This means that it may actually be a blanket term covering a multitude of conditions with a variety of causes.

Confusion may also arise from the fact ADD/ADHD symptoms, vary with each individual, and some mimic those of other causes. (but it has to be said, this is not uncommon - many other conditons have patient specific symptom variations.) A known fact is that, as the body (and brain) matures and grows, the symptoms and adaptability of the individual also change. Many individuals diagnosed with ADD/ADHD successfully develop coping skills, while others may never do so.

Symptoms

• In children the disorder is characterized by inattentiveness to external direction, impulsive behavior and restlessness. However, children with the inattentive type are actually often sluggish and hypo-active.
• In adults the problem is often an inability to structure their lives and plan simple daily tasks. Thus, inattentiveness and restlessness often become secondary problems.

The CDC emphasizes that a diagnosis of ADHD should only be made by trained health care providers. This is important as many of the criteria can be readily misinterpreted and the prescribed drugs can be very dangerous.

Incidence

ADHD is considered by some to be a problem all over the industrialized world, although in no other country are children diagnosed with this disorder as often as in the United States.

According to the 2000 edition of DSM-IV-TR, ADHD affects three to seven percent of all children in the U.S. According to 2002 data from the CDC's annual National Health Interview Survey, released in 2004, nearly 4 million children younger than 18 in the United States had been diagnosed with attention deficit hyperactivity disorder (ADHD). The 2002 data indicated that twice as many boys were diagnosed with ADHD as girls (10% vs. 4%). Some experts theorize that ADHD is under-diagnosed in girls, since their symptoms tend to be less dramatic than those in boys and thus draw less attention from parents and teachers.

A speculative explication for the higher diagnostical quota in the U.S. is reported, e.g. by E. Hallowell. He states that due to the high-risk traits of ADHD-affected people, it can be suggested that there was a higher prevalence for ADHD in the immigrants heading for America in former centuries than in the general population. Assuming that ADHD is inherited this theory might turn out to deserve further consideration. This theory is supported by the report in a study by Olfson (2003) that the ADHD treatment rate amongst Caucasian children is significantly higher than among Afro-Americans (4.4% versus 1.7% in 1997). On the other hand it is also possible that social and other factors may prevail here. A different often related theory links the statistical difference mainly to a presumably higher problem awareness and competence in the U.S. due to the longer research on and public acquaintance with ADHD. Nonetheless, although all of these theories have some support, none of them is considered generally accepted.

Psychological testing for ADHD

Psychological testing for ADHD symptoms generally consists of obtaining multiple types of assessments. These usually include a clinical interview reviewing the DSM-IV criteria for ADHD diagnosis. The interview also needs to rule out as much as possible other types of syndromes which can cause attention problems, such as depression, anxiety, allergies and psychosis. Rating scales can be administered which provide measurement of the person's own view of their symptoms, as well as the views of parents, teachers, and significant others.

Finally, computerized tests of attention can be helpful in providing a further independent assessment. These different assessments may not be consistent, but do provide a view of the person's difficulties. Subjectivity of the analysis can be compounded by the fact that physicians generally need not order psychological testing in order to make the diagnosis of ADHD, but many doctors use this kind of assessment to avoid over-diagnosis and treatment. The process of obtaining referrals for such assessments is being promoted vigorously by the President's New Freedom Commission on Mental Health.

Other forms of testing

Neurometrics, PET scans, or SPECT scans have been used for a more objective diagnosis. However, these are not usually suitable for very young children.

Treatment

There are many options available to treat people diagnosed with ADHD. These options include a variety of medications, behavior-changing therapies, and educational interventions.

Mainstream treatments

The first-line medication used to treat ADHD are mostly stimulants, which work by stimulating the areas of the brain responsible for focus, attention, and impulse control. The use of stimulants to treat a syndrome often characterized by hyperactivity is sometimes referred to as a paradoxical effect. The stimulants used include:

• Methylphenidate -- Available in:
  • Regular formulation, sold as Ritalin, Metadate, Methylin. Duration: 4-6 hours per dose. Usually taken morning, lunchtime, and in some cases, afternoon.
  • Long acting formulation, sold as Ritalin SR, Metadate ER. Duration: 8 hours per dose. Usually taken twice daily.
  • All-day formulation, sold as Ritalin LA, Metadate CD, Concerta. Duration: 10-12 hours per dose. Usually taken once a day.
• Amphetamines --
  • Dextroamphetamine -- Available in:
    • Regular formulation, sold as Dexedrine. Duration: 4-6 hours per dose. Usually taken 2-3 times daily.
    • Long-acting formulation, sold as Dexedrine Spansules. Duration: 8-12 hours per dose. Taken once a day. Also known as dexamphetamine in Australia.
  • Adderall, a trade name for a mixture of dextroamphetamine and laevoamphetamine salts. -- Available in:
    • Regular formulation, Adderall. Duration: 4-6 hours a dose.
    • Long-acting formulation, Adderall XR. Duration: 12 hours. Taken once a day.
  • Methamphetamine -- Available in:
    • Regular formulation, sold as Desoxyn by Ovation Pharmaceutical Company. Usually taken twice daily.
• Atomoxetine. A Selective Norepinephrine Reuptake Inhibitor (SNRI) introduced in 2002, it is the newest class of drug used to treat ADHD, and the first non-stimulant medication to be used as a first-line treatment for ADHD. Available in:
  • Once daily formulation, sold by Eli Lilly and Company as Strattera. Duration: 24 hours per dose. Taken once a day.

Second-line medications include:

• benzphetamine -- a less powerful stimulant. Research on the effectiveness of this drug is not yet complete.
• Provigil/Alertec/modafinil -- Research on this drug is not yet complete.
• Cylert/Pemoline -- a stimulant used with great success until the late 1980s when it was discovered that this medication could cause liver damage. Although some physicians do continue to prescribe Cylert, it can no longer be considered a first-line medicine. In March 2005 the makers of Cylert announced that it would discontinue the medication's production.
• Clonidine -- Initially developed as a treatment for high blood pressure, low doses in evenings and/or afternoons are sometimes used in conjunction with stimulants to help with sleep and because Clonidine sometimes helps moderate impulsive and oppositional behavior and may reduce tics

Because most of the medications used to treat ADHD are Schedule II under the U.S. DEA schedule system, and are considered powerful stimulants with a potential for diversion and abuse, there is controversy surrounding prescribing these drugs for children and adolescents. However, research studying ADHD sufferers who either receive treatment with stimulants or go untreated has indicated that those treated with stimulants are in fact much less likely to abuse any substance than ADHD sufferers who are not treated with stimulants.

Alternative treatments

There are many alternative treatments for ADHD, and all of them are as heavily disputed as the mainstream. This section attempts to deal with the most prominent of the alternative treatments.

Feingold diet

Dr Ben F. Feingold, once a Professor of Allergy in San Francisco, claimed that hyperactivity was increasing in proportion to the level of food additives and proposed a specific diet believing that it would help 50% of hyperactive children.

The Feingold diet excluded cola drinks, chocolate, preservatives and flavor additives, as well as salicylates that occur naturally in fruit such as tomatoes, strawberries, pineapples and oranges. However pineapple juice was suggested as a "safe" drink.

The effectiveness of the Feingold diet has been heavily disputed. Most studies have shown that only 5% of children diagnosed with ADHD benefited from the diet. Other studies have shown a figure of 60%.

Vitamin B₆

In the 1980s the vitamin B₆ promoted as a helpful remedy for children with learning difficulties including inattentiveness. After that, zinc was promoted for ADD and autism. Multivitamins later became the claimed solution. Thus far, no reputable research has appeared to support any of these claims, except in cases of malnutrition.

Neurofeedback

There has been a lot of interesting work done with neurofeedback and ADHD. Children are taught, using video game-like technology, how to control their brain waves. Many professionals consider the treatment promising, but state that there is not yet sufficient evidence that it works after the immediate treatment is complete.

Possible causes

ADHD is broadly defined and pervasive, and the symptoms attributed to ADHD likely have a variety of different causes. The initial triggers could include genetic vulnerabilities, viral or bacterial infections, brain injury, or nutritional deficits. There has been a surge in alternative approaches to ADHD, but these have been vigorously disputed.

A team at the University of California suggest that genes contributing to (ADHD) overlap an area of chromosome 16p13 where genes for Autism can be. The two conditions appear related. Both (ADHD) and autism frequently involve inattentiveness and/or Hyperactivity.

Neuro-chemical imbalance

There is increasing evidence that variants in the gene for the dopamine transporter are related to the development of ADHD (Roman et al., 2004, American Journal of Pharmacogenomics 4:83-92). This evidence is consonant with the theory of inefficacy of dopamine in people with ADD/ADHD; according to other recent studies, people with ADHD usually have relatively high dopamine transporter levels, which clears dopamine from between neurons before the full effect is gained from dopamine. Stimulant medications used to treat ADHD are all capable of either inhibiting the action of dopamine transporter (as methylphenidate does) or promoting the release of dopamine itself (as the amphetamine-class medications do). Therefore, it is theorized that stimulant medication allows the brain to enhance the effect of dopamine by blocking dopamine transporters or increasing the release of dopamine. Currently this is the most widely accepted model of ADD/ADHD etiology in the scientific and medical community.

New studies consider the possibility that norepinephrine also plays a role. (see Krause, Dresel, Krause in Psycho 26/2000 p.199ff).

Smoking during pregnancy

The finding of another possible cause stemmed from the observation that children of women who smoked during pregnancy are more likely to be diagnosed with ADHD (Kotimaa et al., 2003, J Am Acad Child Adol Psychiatry 42, 826-833). Given that nicotine is known to cause hypoxia (too little oxygen) in the uterus, and that hypoxia causes brain damage, smoking during pregnancy could be an important contributing factor leading to ADHD. It may even help explain in part the increase in ADHD diagnoses, as the number of women smokers has increased. However, there are not nearly enough women smoking during pregnancy to account for all the ADHD diagnoses. It is also possible that cause and effect could be confounded in this study, since many mothers who smoke during pregnancy may be ADHD suffers themselves; therefore the cause may simply be the shared genetic material of mother and child, rather than the mother's smoking.

Deficiencies in nutrition

It has been established conclusively that a small percentage of children are sensitive to dyes and other food additives, sugar, caffeine, etc. (Jacobson and Schardt, 1999, Diet, ADHD & Behavior, Center for Science in the Public Interest, Washington, DC).

Nutritional data has been well summarized in a review article (Burgess et al., 2000, Am J Clin Nutr 71:327-330). Children with ADHD have lower levels of key fatty acids. In fact, one study found that the lower the levels, the worse the symptoms. The possibility that fatty acid deficiency is a trigger for ADHD is especially plausible as nutrition scientists have recently demonstrated that the American diet is extremely deficient in omega-3 fatty acids. At the same time, ADHD diagnoses are rapidly increasing. More support for this idea comes from findings that breast-fed children have much lower levels of ADHD, and that until quite recently, infant formula contained NO omega-3 fatty acids.

A recent randomized double-blind experiment comparing a fatty acid supplement with placebo in children with developmental coordination disorder (which exhibits a high degree of overlap with ADHD diagnoses). Fatty acid supplements improved spelling, reading, and behaviour after three months (Richardson and Montgomery, Pediatrics, 2005, 115:1360-1366). While not directly showing a causal link between ADHD and fatty acids, increased levels of fatty acids has a beneficial effect on related behaviour.

However, creating a deficiency of omega-3 fatty acids in pregnant rats produces pups that are hyperactive and that have altered brain levels of dopamine in the same brain regions as seen in humans and other rat models of hyperactivity.

Sleep apnea

There is also new evidence that brief pauses in breathing (apnea) during infancy may be a cause of ADHD. Dr. Glenda Keating of Emory University presented data at the Society for Neuroscience annual meeting in October 2004, showing that repetitive drops in blood oxygen levels in newborn rats similar to that caused by apnea in some human infants is followed by a long-lasting reduction in dopamine levels, associated with ADHD. Apnea occurs in up to 85% of prematurely born human infants. (ScienceDaily)

Head injuries

It has been known for some decades that head injuries can cause a person to experience and display ADHD-like symptoms.

Evidence for ADHD as an organic phenomenon

Brain imaging research using magnetic resonance imaging (MRI) has shown that differences exist between the brains of children with and without ADHD, though these differences have not been shown in any way to be pathological in nature. Additionally PET studies have shown there might be a link between a person's ability to pay continued attention to external directives and the use of glucose - the body's major fuel - in the brain. In adults diagnosed with ADHD, the brain areas that control attention use less glucose and appear to be less active, suggesting that a lower level of activity in some parts of the brain may cause inattention (Zametkin et al.). However, there is no evidence that this low level of glucose in fact causes the low level of attention to external direction; it could in fact be no more than an indicator for low attention, or in the alternative, superior self-direction.

Also worth noting are the results of some studies using SPECT (Single Photon Emission Computed Tomography). One study (Lou et al. in Arch. Neurol. 46(1989) 48-52) found people labeled as ADHD have reduced blood circulation in the striatum. But even more significant may be the discovery that people with ADHD seem to have a significantly higher concentration of dopamine transporters in the striatum (Dougherty et al. in Lancet 354 (1999) 2132-2133; Dresel et al. in Eur.J.Nucl.Med. 25 (1998) 31-39). Researchers have also shown that individuals labeled as either bipolar or ADHD often have variant dopamine receptor alleles. Researchers have reported, for example, that DRD4 7 repeat alleles appear more frequently in certain aboriginal cultures with low population densities such as the Amazon, whereas DRD4 2 repeat alleles are especially common in higher population density regions, including the Orient.

Positive aspects

Though ADHD is classified as a serious disorder, many people have a different perspective and note the positive aspects. ADHD children tend to look at situations in a different manner. They tend to look beyond the norm. "While students are learning the details of photosynthesis, the ADHD kids are staring out the window and pondering if it still works on a cloudy day" (Underwood). Some children might be uneasy about getting into a situation. One positive side of impulsive behavior is the ability to try new things without trepidation. This can be a strength: "Compulsivity isn't always bad. Instead of dithering over a decision, they're willing to take risks" (Underwood). ADHD does not necessarily slow down a person's learning process. In fact, ADHD can contribute to a faster or more comprehensive learning process, especially if teachers implement effective teaching strategies geared specifically towards the ADHD learner. JetBlue founder David Neeleman believes that ADHD contributed to his business acumen.

Some people find hints of ADHD in the lives of many famous people in history. Though such post mortem diagnosis is questionable, it is intriguing to ponder the evidence that people such as Thomas Edison might have been diagnosed as having ADHD if the current DSM criteria had been developed long ago. Other historical figures who have been proposed as ADHD candidates include: , Ludwig van Beethoven, Winston Churchill, Walt Disney, Benjamin Franklin, and John F. Kennedy, Theodore Roosevelt, Woodrow Wilson, and the Wright brothers.

To see ADHD positively may seem somewhat problematic to anxious parents but it is at least a perspective that should be kept in mind. With or without hyperfocus, a common manifestation, ADD/ADHD in combination with successful coping skills may be utilized to achieve remarkable accomplishments. The list of historic figures and persons currently well-known in a wide range of fields who have displayed ADD/ADHD symptoms is impressive and may be source of inspiration.

Adults

Although most diagnoses of ADHD are made for children, the DSM definitions of ADHD do not confine the disorder solely to childhood and in fact many adults are also diagnosed with Adult Attention Deficit Disorder (AADD), which is simply the common label for ADHD in adults. Current theory holds that approximately 30% of children diagnosed retain the disorder as adults. Although the disorder may not have been diagnosed in an individual during childhood, it is also currently thought that all adults with the disorder had it in childhood.

Professionals have noted that adults with ADD/ADHD have often developed more coping skills than children, which make symptoms less noticeable to themselves and others.

See also

• Adult attention-deficit disorder
• ADD psychosis

References

¹Pine DS, Klein RG, Lindy DC, Marshall RD. (1993) Attention-deficit hyperactivity disorder and comorbid psychosis: a review and two clinical presentations. Journal of Clinical Psychiatry, 54 (4), 140-5.
²Opler LA, Frank DM, Ramirez PM. (2001) Psychostimulants in the treatment of adults with psychosis and attention deficit disorder. Annals of the New York Academy of Sciences, 931, 297-301.
³Bellak L, Kay SR, Opler LA. (1987) Attention deficit disorder psychosis as a diagnostic category. Psychiatric Developments, 5 (3), 239-63.

• Center for Neurobehavioral Genetics and Department of Psychiatry and Biobehavioral Sciences, University of California