Attention Deficit/Hyperactivity Disorder(ADHD)

Attention deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder characterized by persistent patterns of inattention, hyperactivity, and impulsivity that interfere with functioning or development. Symptoms usually begin during childhood and may persist into adolescence and adulthood.

ADHD affects academic performance, social relationships, emotional regulation, and daily functioning. The disorder may present predominantly with symptoms of inattention, predominantly with hyperactivity-impulsivity, or as a combined presentation. Early identification and comprehensive management are important to improve educational, behavioral, and psychosocial outcomes.

Epidemiology

ADHD is one of the most common neurodevelopmental disorders of childhood. Symptoms typically become evident during the early school years when demands for attention, organization, and self-control increase.

Although ADHD is commonly diagnosed in childhood, symptoms may continue into adolescence and adulthood. Males are diagnosed more frequently than females, although females may be under-recognized because they often present predominantly with inattentive symptoms.

Risk Factors

Genetic risk factors

• Family history of ADHD

• Family history of other neurodevelopmental disorders

• Genetic susceptibility affecting neurotransmitter regulation

Prenatal and perinatal risk factors

• Prematurity

• Low birth weight

• Maternal substance use during pregnancy

• Perinatal complications

Environmental risk factors

• Exposure to psychosocial stressors

• Adverse childhood experiences

• Family dysfunction

• Exposure to environmental toxins

Pathophysiology

The exact cause of ADHD is not fully understood. Current evidence suggests that ADHD results from a combination of genetic, neurobiological, and environmental factors.

Neurobiological abnormalities may involve:

• Dopaminergic neurotransmission

• Noradrenergic neurotransmission

• Executive functioning networks

• Frontal lobe circuits responsible for attention, impulse control, and behavioral regulation

These abnormalities contribute to difficulties with attention, self-regulation, organization, and impulse control.

Clinical Presentation

Symptoms vary according to age, developmental stage, and ADHD presentation.

Symptoms of inattention

• Difficulty paying attention to details

• Frequent careless mistakes

• Difficulty sustaining attention

• Easily distracted

• Frequent daydreaming

• Appears not to listen when spoken to

• Difficulty following instructions

• Poor organization skills

• Avoidance of tasks requiring sustained mental effort

• Frequently losing items

• Forgetfulness in daily activities

Symptoms of hyperactivity

• Excessive movement

• Fidgeting or squirming

• Inability to remain seated

• Running or climbing excessively

• Excessive talking

• Difficulty engaging quietly in activities

• Constant restlessness

Symptoms of impulsivity

• Interrupting conversations

• Difficulty waiting for turns

• Answering before questions are completed

• Acting without considering consequences

• Intruding on others' activities

Clinical Signs

• Distractibility during assessment

• Difficulty remaining seated

• Excessive talking

• Impaired task completion

• Poor organizational skills

• Academic underachievement

• Behavioral difficulties at home or school

DSM-5 Diagnostic Criteria

According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), an individual diagnosed with ADHD demonstrates functional impairment primarily due to:

• Inattention, and/or

• Hyperactivity and impulsivity

Symptoms must:

• Be present before the age of 12 years.

• Be present in at least two different settings (for example, home, school, social environments, or workplace).

• Cause clinically significant impairment in functioning.

• Not be better explained by another mental disorder.

Inattention criteria

The DSM-5 requires at least six of the following symptoms of inattention for children and adolescents below 17 years of age:

• Failing to pay close attention to details

• Concentration difficulties

• Difficulties with sustaining attention at tasks

• Daydreaming and appearing unable to follow normal conversations

• Difficulties with organization of tasks

• Reluctance to participate in tasks requiring sustained attention

• Frequently loses important objects

• Easily distractible

• Forgetfulness about daily activities

For individuals aged 17 years and above, only five symptoms are required.

Hyperactivity and impulsivity criteria

The DSM-5 requires at least six of the following symptoms:

• Moving about and unable to sit still

• Leaves seat even when required to remain seated

• Climbs or runs about in inappropriate situations

• Always having excessive energy and always on the move

• Chats excessively

• Impulsive and gives answers even before being asked to

• Having difficulties waiting for his or her turn

• Unable to carry out normal conversation due to frequent interruptions

For individuals aged 17 years and above, only five symptoms are required.

DSM-5 Presentations

Predominantly inattentive presentation

The individual primarily exhibits symptoms of inattention with fewer symptoms of hyperactivity and impulsivity.

Predominantly hyperactive-impulsive presentation

The individual primarily exhibits symptoms of hyperactivity and impulsivity.

Combined presentation

The individual fulfills criteria for both inattentive and hyperactive-impulsive symptoms.

Differential Diagnosis

Neurodevelopmental disorders

• Autism spectrum disorder

• Specific learning disorders

• Intellectual disability

• Communication disorders

Psychiatric disorders

• Anxiety disorders

• Depressive disorders

• Bipolar disorder

• Oppositional defiant disorder

• Conduct disorder

Medical conditions

• Hearing impairment

• Visual impairment

• Thyroid disorders

• Sleep disorders

• Epilepsy

Environmental and psychosocial factors

• Psychosocial stress

• Inadequate educational support

• Family dysfunction

• Trauma-related disorders

Investigations

There is no single laboratory test that confirms ADHD. Diagnosis is based primarily on clinical assessment.

Clinical assessment

• Comprehensive developmental history

• Medical history

• Educational history

• Behavioral assessment

• Family assessment

Functional assessment

• Academic functioning

• Social functioning

• Family functioning

• Behavioral performance across different settings

Additional investigations when indicated

• Hearing assessment

• Vision assessment

• Neurodevelopmental evaluation

• Psychological testing

• Assessment for learning disorders

Management

Management should be individualized according to symptom severity, age, functional impairment, educational needs, and family circumstances.

The goals of treatment are to:

• Improve attention and concentration

• Reduce hyperactivity and impulsivity

• Improve academic performance

• Improve social functioning

• Enhance self-esteem

• Improve family functioning

Non-pharmacological treatment

Parent-training and education programmes

Parents should be referred to educational programmes to learn about ADHD, its management, and coping strategies.

For parents

Programmes should include:

• Individual parent-training programmes

• Group-based parent-training programmes

• Education regarding ADHD symptoms

• Behavioral management strategies

• Coping skills for family members

For children and adolescents

Programmes should include:

• Cognitive behavioral therapy (CBT)

• Social skills training

• Emotional regulation strategies

• Problem-solving skills development

Teacher training

Teachers should receive training on behavioral interventions within the classroom to help children cope with ADHD.

These interventions may include:

• Structured classroom routines

• Positive reinforcement techniques

• Task modification strategies

• Improved classroom organization

Behaviour therapy

Behavioural interventions are a cornerstone of ADHD management.

Positive reinforcement

Positive reinforcement encourages desirable behavior through:

• Reward systems

• Praise

• Incentive programmes

• Star charts and behavior tracking systems

Parents may use star charts to promote positive behavior at home.

Environmental modifications

Environmental modifications aim to improve attention and reduce distractions.

Examples include:

• Seating the child in the front row of the classroom

• Minimizing environmental distractions

• Providing structured routines

• Breaking tasks into smaller steps

• Using visual reminders and schedules

Combined interventions

The combination of behavioural therapy and medication is generally more effective than medication alone.

Pharmacological treatment

Pharmacological treatment may be considered for children and adolescents with moderate to severe symptoms causing significant impairment.

Medication should be initiated and monitored according to established ADHD treatment guidelines and individual patient needs.

Principles of pharmacological treatment

• Medication should be used as part of a comprehensive treatment plan.

• Behavioral interventions should continue even when medication is prescribed.

• The lowest effective dose should be used.

• Regular monitoring of treatment response and adverse effects is required.

• Treatment goals should be reviewed periodically.

Referral

Refer the child or adolescent when:

• ADHD is suspected and diagnostic confirmation is required

• Symptoms cause significant functional impairment

• Coexisting psychiatric disorders are present

• Learning difficulties are suspected

• Symptoms fail to respond to initial interventions

• Specialist assessment or treatment is required

Complications

• Academic underachievement

• School dropout

• Behavioral problems

• Low self-esteem

• Social difficulties

• Family conflict

• Anxiety disorders

• Depressive disorders

• Increased risk-taking behavior

• Substance use disorders in later life

Prognosis

The prognosis varies according to symptom severity, age at diagnosis, treatment adherence, family support, and the presence of coexisting conditions.

Many children show significant improvement with appropriate behavioral, educational, and pharmacological interventions. Although symptoms may persist into adulthood, early treatment can substantially improve long-term outcomes.

Prevention

There is no known method of preventing ADHD. However, early identification and intervention can reduce the impact of symptoms and improve functioning.

Important strategies include:

• Early developmental screening

• Prompt assessment of behavioral concerns

• Family education

• School-based support

• Early behavioral interventions

• Management of coexisting conditions

Special Considerations

• ADHD is characterized by persistent patterns of inattention and/or hyperactivity-impulsivity that interfere with functioning.

• Symptoms must be present before the age of 12 years and occur in at least two settings.

• Parent-training programmes and behavioural interventions are essential components of management.

• Teacher involvement is important for successful classroom management.

• Combined behavioural and pharmacological treatment is generally more effective than medication alone.

• Management should be individualized according to the child's developmental and educational needs.