Attention Deficit Hyperactivity Disorder (ADHD) – A Historical Perspective of ADHD

The contemporary concept of attention deficit hyperactivity disorder (ADHD) is widely described by the DSM-IV-TR (American Psychiatric Association, 2000) as a major cause of concern among children. The major manifestations of ADHD have been described in excessive hyperactive, inattentive, and impulsive children, with the early etiological theories being similar to the current descriptions of ADHD. Since the nineteenth century, detailed studied focusing on the behaviors of hyperactive children with added knowledge on brain functions have resulted in better understanding of the inherent behavioral and neuropathological deficits underlying the disorder. Currently, most children with Attention Deficit Hyperactivity Disorder are identified based on their symptoms, with most of them being identified and treated in primary school.

Population studies have concluded that five percent of children across the globe elicit impaired attention levels, as well as hyperactivity. The studies have classified boys as suffering from ADHD as being approximately twice as frequently as girls and primary age children as being approximately twice as frequently as adolescents. The existence of ADHD symptoms is on a continuum in the general population, with the disorder being considered to a greater or lesser degree based on the identification, (e.g., parent or teacher), the perceived extent of functional impairment, the criteria used in diagnosing the condition, and the threshold chosen in defining the case under observation. Available literature indicates that developmentally inexcessive levels of inattention or overactivity and impulsive characteristics of ADHD are present among cases from an early age. However, among preschoolers with early signs of ADHD may also present with co-occurring oppositional noncompliant behaviors, temper tantrums and being overly aggressive that may overshadow symptoms of inattention and overactivity, consequently confounding the diagnosis.

, a psychiatrist who treats this condition in adults, “Inattentiveness tends to be less obvious in adults and often goes unnoticed to the untrained eye. Unfortunately, many physicians and those in the medical community are not convinced that ADHD continues well into adulthood.”

In the early nineteenth century, ADHD medication was based on a sequelae among survivors of the Spanish influenza epidemic, whereby it was postulated that the source of ADHD was a neurological disturbance (minimal brain damage), although the fact was displayed only by children in the post-influenza reaction. As such, many social events nudged the development of theoretical constructs with some pointing towards a combination of genetic, biological, social, and evolutionary effects. Therefore, it was necessary to address the underlying issue with the discovery of l-amphetamine in 1932 by Charles Bradley making a breakthrough in the paradoxical treatment of some children. The impact of this development persisted as the sole pharmacologically viable solution until 50 years later when it was observed that the calming and focusing effects of stimulants were positive in both normal and ADHD children, with age rather than susceptibility, being the defining feature of the drug’s effect on the children.

Parallel to these ADHD pharmacological developments was the creation of diagnostic categories, psychometric instruments, as well as definitions that proceeded in both derivation and shaping the understanding of ADHD as a heterogeneous disorder. More controversy around accurate diagnosis was heightened with increase in diagnosis of younger children in addition to discovery of new medications for psychoactive medications. In the United States, an approximated 150,000 to 200,000 children were subjected to stimulant treatment by the end of the 1960s, and as of 2005, it is estimated that 4.4 million children have been diagnosed with ADHD, with 56 percent of them receiving medication. Psychostimulants have been widely prescribed since 1971, when they recategorized as Schedule II controlled substances subject to mandatory reporting requirements.

Even though methylphenidate (MPH) has been used as a controlled substance, it has attracted lots of concern; considering that it appears to be widely available beyond the common medical access points such as through internet sources as well as increased use as a study aid in many universities. The main concern revolves on considerations that the evidence creates a mismatch between the people who get diagnosed and those who get prescribed. As study by Tuber, Harris, Meehan, Reynoso, & Ueng-McHale (2007) points at a definite diagnosis prevalence of ADHD as being 0.9 percent in the population (based on interviews with parents), while the Psychostimulants treatment doubles the initial findings, with majority of those using the medication meeting partial but not full diagnostic criteria. Other studies on the same don not find such strong of a wide mismatch as reported in the study.

In managing the symptoms of ADHD, many psychostimulants medications such as MPH, dextroamphetamine (DEX), or mixed amphetamine salts (MAS) have been found and consequently approved by the FDA as being able to decrease the core symptoms of ADHD and other associated impairments (Tomas, 2004). Although the drugs’ mechanisms have been found to be effective to a larger extent, some preparations have been found to last only a few hours, with the symptoms setting in as soon as the medication wears off. With many families preferring to use the medications on school-aged children and youth aged 6 years and below, it has been documented that psychostimulants, most commonly MPH and DEX, are safe and well tolerated among children. However, the side effects are a major concern including insomnia, headaches, stomachaches, increased blood pressure and heart rate.

Similarly, use of the psychostimulants on long-term has been found to result in decreased growth rate, which in most cases is considered to be clinically insignificant. Other concerns raised after post marketing surveillance suggests rare incidences of sudden death, which is perhaps associated with pre-existing cardiac defects. However, the rate appears not to exceed that of the base rate of sudden death among people in a selected geographical area. As noted earlier, in the United States, an approximated 150,000 to 200,000 children were subjected to stimulant treatment by the end of the 1960s, and as of 2005, it is estimated that 4.4 million children have been diagnosed with ADHD, with 56 percent of them receiving medication (Stieglitz, 2005).

In recent years, several extended preparations of psychostimulants have been released with focus on improving adherence and symptom control throughout the day, as well as remarkable decrease in potential of the drugs being abused. As a result, non-stimulants such as alpha adrenergic agents and atomoxetine (ATX) have been developed, with findings indicating their usefulness in managing symptoms with few associated adverse events among users. However, the main concern remains that the effect of the medications wears off upon discontinuation. Considering that ADHD is a chronic disorder, many children, teens, and adults are required to stay on medications for longer periods.

In conclusion, the possibility of cumulative effects over time is high, with review of evidence suggesting that the benefits and risks of prolonged medication for ADHD are relatively equal among many patients. Even with the existence of nonpharmacologic interventions as a complement to pharmacological interventions. Behavioral training has been found to be a helpful intervention in the management of ADHD, as a primary management intervention for disruptive behaviors that in most cases coincide with ADHD. Since ADHD may begin before school age, a common precedent is being noted among older children, with an increasing number of preschoolers being identified and treated, sometimes with medications (Duff, 2008). The most commonly used psychostimulant is MPH, although it has not received government regulatory approval for use in children aged below 6 years of age. On the other hand, MAS has been granted FDA approval in the United States to be used for children under 6 years, but older than 3 years of age. Recent reviews of treatments for preschoolers with ADHD have emphasized the use of psychostimulants alongside parenting interventions, which is based on general clinical consensus guidelines.

References

  • American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (DSM-II). Washington DC: American Psychiatric Association.
  • Duff, J. (2008). ADHD. Journal of Complementary Medicine, 52-55.
  • Stieglitz, R. D. (2005). Attention-deficit hyperactivity disorder in adults : diagnosis and prevalence. Attention-deficit hyperactivity disorder (ADHD) in adults, 105-125.
  • Tomas, L. (2004). ADHD. Journal of Complementary Medicine, 24-30.
  • Tuber, S., Harris, B. H., Meehan, K. B., Reynoso, J. S., & Ueng-McHale, J. (2007). Rorschach configurations of children with ADHD. The clinical assessment of children and adolescents, 449-465.