ADHD is a neurodevelopmental disorder marked by inattention and hyperactivity-impulsivity. It impacts daily functioning across multiple settings, with symptoms starting before age 12. There are three subtypes: predominantly inattentive, predominantly hyperactive-impulsive, and combined.

ADHD has biological, psychological, and environmental causes. It affects academic, social, and occupational functioning. Treatment options include medication (stimulants and non-stimulants) and non-pharmacological approaches like behavioral therapy, CBT, and educational interventions.

Overview of Attention-Deficit/Hyperactivity Disorder (ADHD)

Primary symptoms of ADHD

• Neurodevelopmental disorder marked by persistent inattention and/or hyperactivity-impulsivity interfering with functioning or development
• Symptoms present before age 12 occur in multiple settings (home, school, work)
• Inattention symptoms involve difficulty sustaining focus, distractibility, failing to follow instructions or complete tasks, avoiding mentally demanding activities, losing important items, forgetfulness in daily routines
• Hyperactivity-impulsivity symptoms include fidgeting or squirming, trouble staying seated, excessive running or climbing (children), difficulty with quiet activities, constantly "on the go" or "driven by a motor," excessive talking, blurting out answers or interrupting, struggling to wait for turns

Subtypes of ADHD

• Predominantly Inattentive Type (ADHD-PI) primarily exhibits inattention symptoms may appear sluggish, daydreamy, easily confused
• Predominantly Hyperactive-Impulsive Type (ADHD-HI) mainly shows hyperactivity-impulsivity symptoms appears restless, fidgety, disruptive
• Combined Type (ADHD-C) displays both inattention and hyperactivity-impulsivity most common subtype
• Symptom presentation can shift over time leading to changes in subtype diagnosis

Etiology and Impact of ADHD

Contributing factors for ADHD

• Biological factors
  • Genetic influences with 60-90% heritability
  • Neurochemical imbalances in dopamine and norepinephrine systems
  • Structural and functional brain differences (reduced volume in prefrontal cortex and striatum)
• Psychological factors
  • Executive functioning deficits (working memory, inhibitory control, cognitive flexibility)
  • Emotional regulation and motivation difficulties
• Environmental factors
  • Prenatal substance exposure (alcohol, tobacco)
  • Low birth weight and prematurity
  • Toxin exposure (lead)
  • Family dysfunction and adverse childhood experiences

Impact of ADHD on functioning

• Academic functioning impairments
  • Difficulty completing assignments and studying effectively
  • Lower grades and higher academic underachievement rates
  • Increased school dropout risk
• Social functioning challenges
  • Trouble maintaining friendships and relationships
  • Impaired social skills and problem-solving abilities
  • Higher peer rejection and social isolation rates
• Occupational functioning issues
  • Difficulty maintaining employment
  • Lower job performance and productivity
  • Increased workplace accidents and injuries risk

Treatment of ADHD

Treatments for ADHD

• Pharmacological treatments
  1. Stimulant medications (methylphenidate, amphetamines)
     • Increase dopamine and norepinephrine brain levels
     • Improve attention, reduce hyperactivity and impulsivity
  2. Non-stimulant medications (atomoxetine, guanfacine)
     • Increase norepinephrine or activate alpha-2 adrenergic receptors
     • Improve attention and reduce hyperactivity
• Non-pharmacological treatments
  1. Behavioral therapy teaches strategies for managing symptoms and improving functioning (positive reinforcement, time management, organizational skills training)
  2. Cognitive-behavioral therapy (CBT) addresses maladaptive thoughts and behaviors develops coping strategies and problem-solving skills
  3. Parent training and education teaches strategies for managing child's behavior and creating supportive home environment
  4. Educational interventions and accommodations include individualized education plans (IEPs), classroom modifications, assistive technology