Attention Deficit Hyperactivity Disorder

July 1, 2021 Rima Pharmacology 0

  • Attention deficit hyperactivity disorder or ADHD is a condition characterized by high level of impulsivity, hyperactivity and inattention. It is one of the most common neurodevelopmental disorder occurring in childhood. The symptoms of ADHD may begin in childhood and may continue up to teenage and adolescence. 
  • If ADHD is left untreated in childhood, it may result in poor psychosocial outcomes.
  • Epidemiological data suggests that ADHD affect around 5% of children and adolescents and around 2.5% of adult population worldwide. 

Signs and symptoms of Attention Deficit Hyperactivity Disorder

  • Signs and symptoms are mainly of three different patterns:
    • Inattention (difficulty in paying attention).
    • Hyperactivity (over activeness).
    • Impulsivity (Acting or responding without thinking).

Inattention

  • People with symptoms of inattention may show following habits which affect their daily life. 
  • Forgetting or losing things.
  • Daydreaming a lot. 
  • Difficulty in following instructions like doing homework or doing duties in workplace.
  • Difficulty in organizing activities like keeping work organized, submitting work within deadlines, keeping materials in order. 
  • Making careless mistakes. 
  • Easily distracted. They may start some work, easily lose focus and get sidetracked. 
  • Difficulty in getting along with others. 

Impulsivity/Hyperactivity

  • Fidgeting and squirming while seated. 
  • They may be hyperactive (always moving, getting up and rotating or moving in situation when staying seated is expected). 
  • Difficulty to play or engage in any work quietly. 
  • Talking a lot. 

Types of Attention Deficit Hyperactivity Disorder

Depending on which symptoms are more prevalent in patient, ADHD can be classified into three different types. These symptoms are not constant. They can change over time. 

Predominantly Inattentive presentation

  • Individual may have difficulty in paying attention or following instructions. 

Predominantly hyperactivity/impulsive presentation

  • Individual is hyperactive and impulsive. They may jump or run constantly. Impulsive people speak before other complete their sentences, may blurt answer before question is completed.  

Combined

  • The individual may show symptoms of both inattentiveness and hyperactivity/impulsiveness. Most of the children have combined type of ADHD. 

Causes

  • There is not a single factor or cause that may cause ADHD. It may be caused due to combination of several genetic and environmental risk factors. 
  • Some of the possible causes and risk factors include:
    • Brain injury
    • Low birth weight
    • Smoking, alcohol or drug use by mother during or pregnancy. 
    • Exposure to environmental toxins during pregnancy or during young age.
    • Prevalence of ADHD is highly influenced by genetic factors. Relatives of ADHD children are at high risk of ADHD or other comorbid psychiatric disorder. 

Psychiatric comorbidity

  • It is associated with other psychiatric disorder like mood and anxiety disorder, substance abuse, oppositional defiant disorder j(ODD), conduct disorder etc. 
  • ADHD increases chance of having depressive disorder by two times. ADHD patients may also have various anxiety symptoms. 
  • Child with ADHD may have increased risk of developing habits of cigarette smoking or drug abuse in teenage. Certain research suggests that individual with ADHD may have more severe form of substance abuse and may have habit of substance abuse for longer time compared to individual without ADHD. 

Treatment of ADHD

  • There is no cure for ADHD. The treatment available helps to improve symptoms and improve quality of life. The treatment of ADHD includes non- pharmacological treatment and pharmacotherapy. Non- pharmacological treatment includes individual and family psychotherapy and educational remediation. 
  • In pre-school children, parent training program (PTP) is recommended first. Any medication treatment is not preferred in them. In school going children with ADHD, psychological treatment for child and PTP for parents is offered. Medications are used when psychological treatment is not sufficient to improve the symptoms. 
  • In school age children with severe impairment secondary to ADHD symptoms, pharmacotherapy is found to be more effective than PTP or other psychological therapy. Behavioral therapy can be used as add on therapy with medications. 
  • Psychosocial therapy is based on four main principles:
    • Rewarding positive behavior.
    • Ignoring inappropriate behavior. 
    • Punishing unacceptable behavior and 
    • Adjusting activities to child’s ability. 
  • Medications used for treating ADHD include stimulants, non-stimulants like atomoxetine, guanfacine. Some antidepressants can be used to manage ADHD in adults though they are not FDA approved for treating ADHD. 
  • Stimulants are first line agents preferred in children and adults with ADHD. They may be methylphenidate based or amphetamine based and act by increasing intrasynaptic catecholamines. Atomoxetine is potent inhibitor of reuptake of norepinephrine. It is also effective in comorbid ADHD.

References

  1. Ougrin et al. Attention Deficit Hyperactivity Disorder (ADHD): review for primary care clinicians. London J Prim Care (Abingdon). 2010 Jul; 3(1): 45–51.
  2. Wilens Te et al. Understanding Attention-Deficit/Hyperactivity Disorder from Childhood to Adulthood. Postgrad Med. Postgrad Med. 2010 Sep; 122(5): 97–109.
  3. Faraone, S., Asherson, P., Banaschewski, T. et al. Attention-deficit/hyperactivity disorder. Nat Rev Dis Primers 1, 15020 (2015).