Section C - Childhood conditions

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Part 1 - Attention-deficit/hyperactivity disorder
Part 2 - Pervasive developmental disorders
Part 3 - Separation anxiety disorder

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The conditions described in this section are the most common mental health disorders in childhood, including attention-deficit/hyperactivity disorder (ADHD), autistic disorder, Asperger's disorder, and separation anxiety disorder. Each of these disorders, by definition, has a diagnosis before 18 years of age. attention-deficit/hyperactivity disorder affects about 5% of the school-age population and contributes to poor school performance, conduct disorders, and difficulties in family and friend relationships.7,65,66 Autistic disorder and Asperger's disorder are pervasive developmental disorders (PDDs), which are characterized by significant impairment in specific areas of development, such as social interaction skills and/or communication skills, as well as the presence of stereotyped behaviour, activities or interests.7 The distinction between autistic disorder and Asperger's disorder is generally made in terms of severity: autistic disorder is at the lowest functioning end of the PDD continuum, whereas Asperger's relates to the mildest and highest functioning end of the continuum.7,67,68 Finally, separation anxiety disorder is a disorder typically in children that is characterized by a fear of being alone or being without an individual the child is attached to, usually a parent.

Part 1 - Attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is characterized by inattention, hyperactivity and impulsivity, and is one of the most common mental health conditions in children.7,65,66 Boys are three times more likely to develop ADHD than girls.66 Symptoms of ADHD usually arise between the ages of three and five but are typically most prominent in the elementary school grades and often persist throughout adulthood. In fact, approximately 75% of cases will continue to have the diagnosis through adolescence, and over half of the cases continue into adulthood.69 Severity of childhood ADHD and treatment of ADHD in childhood has been found to predict adult ADHD.70 The functional limitations described in this section refer to the health state of a child diagnosed with ADHD; those associated with an adult are not captured here.

The DSM-IV makes a clinical diagnosis of ADHD based on the presentation and persistence of symptoms. Depending on which symptoms (pattern) are predominant over the past six months, diagnosis can be one of three subtypes. An individual is diagnosed with ADHD–predominantly inattentive type, if they have six or more of the following symptoms of inattention: often pays little attention to details or makes careless mistakes in school/work; has difficulty staying attentive in tasks or activities; seems not to listen when spoken to directly; fails to finish a task or does not follow through on instructions; often has difficulty with organizing tasks and activities; either avoids, dislikes, or is reluctant to partake in tasks that require sustained effort (e.g., schoolwork, homework); often misplaces items that are required for tasks or activities; is easily distracted by external stimuli; and/or is often forgetful in daily activities. An individual is diagnosed with ADHD–predominantly hyperactive-impulsive type, if they have six or more of the following symptoms of hyperactivity or impulsivity: often fidgets or squirms; often leaves seat/chair when remaining seated is expected; often runs around in inappropriate situations; has difficulty playing quietly; is often "on the go"; often talks excessively; often blurts out answers to questions that have not been completed; has difficulty waiting their turn; or often interrupts/intrudes others. The third subtype of ADHD is ADHD–combined type, in which the individual has at least six of the inattentive symptoms and at least 6 of the hyperactive-impulsive symptoms. Additional criteria for making these diagnoses are that some symptoms (that cause impairment) must have been present before seven years of age, and some impairment must be shown in at least two settings (e.g., school, home). Finally, it must be evident that the symptoms are causing clinically significant impairment in social, academic, or occupational functioning, and the symptoms do not occur during the course of, or are not better accounted for, another mental disorder.7

The majority of children with ADHD have combined type;7 therefore, it is the subtype we describe in this section.

The underlying causes of ADHD are unknown at this time. Some assume that it stems from the home environment (i.e., allowing the child to watch too much television or consume excess sugar), but there are likely genetic influences; ADHD has been found to be more common in first-degree biological relatives of children with ADHD than in the general population.7,71 Non-genetic factors that may be linked to ADHD include premature birth, exposure to high levels of lead in early childhood, brain injuries, and the maternal use of alcohol or tobacco. There are theories that ADHD arises as a developmental failure in the brain that impairs self-control and inhibition.71

The most effective treatment for ADHD is currently considered to be a combination of medication with psychotherapy, behavioural therapy, and/or emotional counseling. Ritalin (a short-acting methylphenidate) is the most common medication and helps to reduce hyperactivity and improve the ability to focus, work and learn. Other medications with similar effects include dextroamphetamine (Dexadrine or Dextrostat), pemoline (Cylert) and Adderall. Medication should not be taken indefinitely and is often discontinued to assess the child's condition. Psychotherapy is another mode of treatment that helps individuals with ADHD to learn new behaviours that will raise self-esteem and teach them how to deal with the emotional effects of ADHD. Parents may also be encouraged to attend skills training in order to learn techniques for managing their child's behaviour.72

Attention-deficit/hyperactivity disorder – combined type

ICD-9: 314.01 ICD-10 - Attention-deficit/hyperactivity disorder F90.0

This health state describes a child diagnosed with ADHD-combined type who is currently taking a psychostimulant medication (i.e., Ritalin) as a form of treatment. Insomnia and appetite suppression are the two most common side effects. The major symptoms of ADHD-combined type are inattention, hyperactivity and impulsivity. Children with ADHD-combined type have a hard time keeping their minds on a specific task and may get bored after only a few minutes. Concentration, organization, and completion of tasks (particularly for a new task) are difficult. Consequently, the child often suffers low academic achievement and poor school performance, and has more school suspensions and expulsions, leading to conflict with parents and teachers (and other school authorities). Hyperactivity is characterized by fidgeting and squirming, bouncing from task to task, and excessive talking. Impulsivity is manifested by impatience: the child may not think before they act, which may lead to participation in potentially dangerous activities without consideration of the consequences. In general, individuals with the disorder have difficulties in adapting to the demands of social life and often fail to reach the goals they strive for themselves. Children with ADHD also have a difficult time making and keeping friends, and family relationships are impaired.  The child with ADHD is often punished for being disruptive and thought of as lazy or irresponsible due to their lack of self-application.7,71 Fine and gross motor abilities development may be slightly impaired in some cases.73 Many of these children experience more depressive symptoms in comparison to children without ADHD.74

Classification Attention-deficit/hyperactivity disorder – combined type)

Part 2 - Pervasive developmental disorders

Pervasive developmental disorders (PDDs) are disorders that cause significant impairment in several areas of development, including social interaction skills, verbal and non-verbal communication skills, and/or the presence of stereotyped behaviour, interests and activities.7 In general, these impairments become evident as the child fails to meet age-appropriate development, as compared to other children the same age. In the majority of cases, individuals are diagnosed before three years of age.

There are five PDDs in the DSM-IV, each with their own specific diagnostic criteria: autistic disorder, Asperger's disorder, Rett's disorder, childhood disintegrative disorder, and pervasive developmental disorder not otherwise specified.7 These PDDs are defined based on the number and type of symptoms present, which could range from mild to severe, or the age of onset of the symptoms. This section describes the health states associated with a diagnosis of autistic disorder and of Asperger's disorder, as they are the most common of the PDDs.

Part 2a - Autistic disorder

Autistic disorder is a lifelong pervasive developmental disorder that affects all of mental development. It is at the opposite end of the PDD continuum from Asperger's and is more involved with lower functioning. Specifically, autistic disorder is characterized by impaired social interaction and communication, as well as behaviour patterns that are repetitive and restricted. It is the most prevalent of the PDDs, with prevalence rates ranging from 2 to 20 cases per 10,000.7,75,76,77 Rates are 4-5 times higher in males than females.7,78 Although onset is typically prior to age three years, most children are not diagnosed before age four76,78 because symptoms of the disorder are difficult to identify in infancy. Possible signs during infancy include lack of eye contact and/or facial responsiveness, a failure to respond to parents' voices, and a lack of protective reflexes when falling. Symptoms become more noticeable as the child falls farther behind in development compared with other children the same age.

Autistic disorder is defined as a spectrum disorder because it affects each individual differently and at varying degrees. Approximately 30% of individuals with autistic disorder are high functioning (have a normal IQ),75 while the majority have at least some degree of mental retardation.75,77 At least half of individuals with autistic disorder learn to speak, but many others are mute. Those that can speak tend to use language in unusual ways: some may not be able to combine words into a meaningful sentence; some repeat words as a parrot would (referred to as echolalia); others may only be able to speak single words.

Diagnosis of autistic disorder is based on observation of the individual's communication, behaviour, and developmental levels. Diagnosis is made if the individual has at least six or more of the following items: 1) qualitative impairment in social interaction as seen in at least two of the following: a) marked impairment in nonverbal behaviours; b) failure to develop relationships with peers at the appropriate developmental level; c) lack of wanting to share enjoyment or interests with others; d) lack of social or emotional reciprocity; 2) qualitative impairments in communication as seen in at least one of the following: a) delay in or lack of the development of spoken language; b) marked impairment in initiating or sustaining a conversation (among individuals who do speak); c) peculiar or repetitive use of language; d) lack of make-believe or social imitative play at the appropriate developmental level; and 3) at least one of the following that is evidence for restricted repetitive patterns of behaviour: a) preoccupation with restricted patterns of interest that are abnormal in either intensity or focus; b) inflexible adherence to non-functional routines or rituals; c) repetitive motor mannerisms; and d) persistent preoccupation with parts of objects. In addition to these items, the disturbance must be apparent by delays or abnormal functioning in at least one of social interaction, language as used in social communication, or symbolic or imaginative play, prior to three years of age. Finally, these disturbances must not be better accounted for by Rett's disorder or childhood disintegrative disorder.7

Though no specific cause of autistic disorder has been identified, there is evidence for a strong genetic component. Current heritability estimates are above 90%,79,80 although no one gene has been identified. Parents who already have a child with autistic disorder are at increased risk for having another one with autistic disorder, a risk of approximately 3% (50+ times higher than the population rate).77,81,82 This risk extends to other forms of PDDs, such as Asperger's disorder. Non-genetic factors are associated with disruption of normal brain development, and usually occur prenatally. Examples include prenatal exposure to a viral infection, use of maternal anticonvulsants, and hypothyroidism or other medical conditions of the mother.83,84,85

There are several approaches for treatment of autistic disorder. Interventions typically consist of highly structured, specialized education programs that are tailored to the individual. These interventions target specific areas of communication, social skills, play, cognition, and independence. Individuals with more severe impairments may require education in managing the basic needs and tasks for daily living. Medications may be prescribed to treat specific symptoms if those symptoms pose a threat to the child or interfere with patient education,86 such as aggression or self-injurious behaviour. Behavioural approaches focus on rewarding the child each time they attempt or perform a new skill, in order for the child to perform it more often. Parental involvement in any treatment program is a factor for greater success. In general, the earlier treatment begins, the more opportunities there are for learning; in turn, the child's developmental rates, particularly skill and language development, may improve.83

Autistic disorder

ICD-9: 299.0 ICD-10 Childhood autism – F84.0

Individuals with autistic disorder experience significant impairments in communication; engaging in a meaningful conversation can be extremely difficult. The inability to communicate effectively contributes to frustration – the individual may not be able to tell others what he/she needs and therefore may simply scream or throw things. Hearing capacity is usually normal although some individuals with autistic disorder act as if they are deaf; some are particularly sensitive (often painfully) to sound. Social interaction is also limited. Though it is hard to estimate the functional limitations associated with the use of hands and fingers, typically their fine motor skills are either underdeveloped or not used properly, or both. Individuals with autistic disorder have a difficult time forming relationships with others, and are often teased and tormented by peers. They tend to have a preference for being alone, provide little or no eye contact, and are non-responsive to verbal cues or normal teaching methods. Aggressive behaviour toward others or self may be present; temper tantrums are not uncommon in young children. Often individuals with autistic disorder have an obsessive interest in a single item, idea or person. They tend to have their own routines and rituals, engage in repetitive activities (e.g., rocking or banging their head), and are resistant to change in daily routines (for example, if their toothbrush has been moved, they may get very upset). Walking, bathing or dressing themselves may be difficult due to their inflexible and rigid behaviours.7,83,85

Classification (Autistic disorder)

Part 2b - Asperger's disorder

Asperger's disorder, or Asperger syndrome, refers to the mildest and highest functioning end of the pervasive development disorder continuum, and is characterised by delays in the development of social skills and behaviour. While there are some similarities to autistic disorder, there are also some very important differences. The unusual restricted and repetitive patterns of behaviour and activities, as well as severe and sustained impairment in social interactions, are common features of both Asperger's and autistic disorder. However, individuals with autistic disorder tend to be socially isolated, whereas individuals with Asperger's are motivated to approach others. In addition, individuals with autistic disorder tend to have a preoccupation with parts of objects or rituals whereas those with Asperger's are more likely to be completely encompassed in a topic about which they may spend endless time learning. As well, a child with Asperger's does not show the same delays as a child with autistic disorder in the areas of cognitive development or developing language skills.67,68

Asperger's disorder is diagnosed if the individual has qualitative impairment in social interaction, as seen by two or more of the following: a) marked impairment in multiple nonverbal cues such as eye contact or facial expressions; b) failure to develop relationships with peers at the appropriate developmental level; c) a lack of seeking shared enjoyment or interests with others; and/or d) a lack of social or emotional reciprocity. The individual also shows restricted repetitive and stereotyped patterns of behaviour, as evidenced by any of the following: an abnormally intense preoccupation with one or more stereotyped and restricted patterns of interest; inflexible adherence to specific, non-functional routines/rituals; stereotyped and repetitive motor mannerisms (e.g., hand or finger flapping); and/or persistent preoccupation with parts of objects. These symptoms cause clinically significant impairment in social, occupational or other areas of functioning. Finally, there is neither a clinically significant delay in language or cognitive development, nor in age-appropriate self-help skills, adaptive behaviour, or curiosity about the environment.7

Prevalence of Asperger's disorder is comparable to autistic disorder; prevalence rates for Asperger's have ranged from 2.5 to 36 per 10,000,75,87 with boys at least four times more likely to have the disorder than girls.7,87 Onset is typically between the ages of two and six years but it is often not recognized until later (average age at diagnosis is around 7 to 11 years),88,89 possibly as late as young adulthood. This is likely because language and cognitive skills are considered normal; it is not until the child enters pre-school that the social difficulties become apparent. These social difficulties often become more striking over time.7 It has been found that children with severe language impairments have been shown to receive a diagnosis (1.2 years) earlier than other children, whereas children with hearing impairments receive a diagnosis (10 months) later than other children.88 Similar to autistic disorder, no single cause has been identified, but there is likely a genetic component. There is a higher risk for Asperger's and other autism spectrum disorders in family members of an affected child.7

Though the majority of individuals with Asperger's disorder improve with age, early diagnosis and treatment is optimal for long-term prognosis. Treatment of Asperger's disorder is most effective when multiple therapies are combined and customized to the child's developmental and behavioural needs. Psychotherapy, behaviour modification, social skills training programs, and familial/parental education and support are interventions that aid the individual and their family to cope more effectively with changing social goals and demands.90,91,92,93 Educational interventions (i.e., special education services) may be required, particularly when the goal is to integrate the individual into a regular classroom.68,94 Some pharmacological interventions may be prescribed to alleviate associated symptoms of Asperger's, such as hyperactivity or depression. Individuals with Asperger's often complete high levels of education, gain employment and live independently.

Asperger's disorder

ICD-9: 299.8 ICD-10 – Asperger's syndrome F84.5

An individual with Asperger's disorder experiences delays in the development of social skills and behaviour. As opposed to autistic disorder, language development is normal: the individual likely has an extensive vocabulary and most have strong verbal skills. Often speech is pedantic (putting excessive emphasis on details) and formal. There are some difficulties, however, with nonverbal communication such as facial expressions or body posture. Verbal communication may be impaired and is likely due to social dysfunction: the individual often fails to adhere to the give-and-take of a conversation and will pursue/maintain a topic that may be inappropriate. Mentally, individuals with Asperger's have average or above average intelligence (IQ). Often the individual will have intense preoccupations about a certain topic or interest, and possess extensive knowledge of facts and information on that topic. For some individuals, this preoccupation will remain through adulthood and form the basis for their career; in others, this area of preoccupation will be replaced by another. Clumsiness and poor motor skills may be apparent, particularly in the use of hands and fingers. Many individuals with Asperger's have a tendency to rock or pace while concentrating; hyperactivity is often present. Repetitive and restrictive behaviour is common and the individual is likely resistant to change. Individuals with Asperger's are typically considered socially awkward. They experience difficulties in social interaction, appear to be uninterested in sharing interests or experiences, tend to be unaware of occurrences in their surroundings, and are egocentric. Despite the desire to fit in socially, they are often viewed by peers as odd and therefore experience social isolation, peer rejection and frequently are victims of bullying. As adults, social interaction likely improves but can be challenged by the demands of marriage (and/or living with others) and working with other people.7,67,68

Classification (Asperger's disorder)

Part 3 - Separation anxiety disorder

Separation anxiety disorder (SAD) is a disorder usually first diagnosed in childhood or adolescence, and is characterized by excessive anxiety of separation from the home or from people to whom the individual is attached (e.g., parents). Although there is a period in childhood during which it is developmentally appropriate (12-24 months of age) to experience separation anxiety, individuals with SAD experience extreme anxiety over long periods of time. The individual becomes markedly afraid to leave an attachment figure because they fear that if they are apart, something bad will happen to prevent their re-uniting, such as death or an accident. The individual with SAD may undergo temper tantrums or experience a panic attack. Many refuse to participate in activities outside the home; about 75% of individuals refuse to go to school.95 Consequently, SAD significantly interferes with academic and social functioning.

SAD typically develops in middle childhood, but early onset can occur before six age years of age.7 Rarely, SAD will develop in adulthood. It is often first diagnosed when the child begins school. Lifetime prevalence rates are between 3% and 5%;7,14,95,96,97,98 prevalence decreases with age. SAD is more common in females than males.7,98,99 Most children with SAD grow out of the disorder; approximately one-third of cases persist into adulthood.98 The typical course involves periods of exacerbation and remission. The higher the number of SAD symptoms, the more likely SAD will persist. Moreover, individuals with persistent SAD tend to receive at least one comorbid diagnosis.100

The DSM-IV diagnoses SAD if the individual experiences excessive anxiety when faced with separation from home or from someone the individual is attached to. This anxiety must be developmentally inappropriate, and manifested by at least three of the following: recurrent excessive distress when anticipating separation from home or someone the individual is attached to; persistent and excessive worry about losing major attachment figures or attachment figures being harmed; persistent and excessive worry about getting lost or another event in which the individual will never reunite with the major attachment figure; persistent unwillingness or refusal to go to school or other locations due to fear of separation; persistent and excessive fear or reluctance to be alone or without major attachment figures at home; persistent unwillingness or refusal to sleep unless near a major attachment figure or refusal to sleep away from home; recurrent nightmares revolving around separation; and/or repeated complaints of physical symptoms (e.g., headache, nausea) when faced with or anticipating separation from someone the individual is attached to. These symptoms must have been present for at least four weeks and onset before age 18 years. Finally, the disturbances from SAD cause significant impairment in social, academic/occupational, or other area of functioning.7

SAD may develop after a highly stressful life event, such as the death of a parent. Although there is no particular cause, there is some evidence that its development has a genetic contribution; twin and adoption studies have shown that children who have a biological relative with the disorder are more likely to develop SAD than the general population.7,96,97 Parental factors also seem to play a role; SAD is more common in the offspring of women with panic disorder,7 or other anxiety or depressive disorders.96,97 Individuals with SAD typically have other anxiety or depressive disorders themselves, particularly social anxiety and panic disorder.97

The most widely used mode of treatment for SAD is psychotherapy. Cognitive-behavioural therapy teaches the child to identify their unrealistic fears and anxious thinking and develop more appropriate coping strategies to reduce the anxiety. Exposure therapy is a form of psychotherapy in which the individual is gradually exposed to anxiety-causing separation (by slowly increasing the distance from parents or other major attachment figures). This forces the individual with SAD to confront their fears with the goal of reducing their anxiety over time. Family therapy may also be recommended; parents can learn more about the disorder and its consequences, and they can learn how to help encourage their child to face new situations and avoid excessive criticism. Rewards and praise are sometimes effective. Medication therapy is typically only required if the individual has persistent symptoms after attempting psychotherapy; an antidepressant may help if the individual is also depressed.97

Separation anxiety disorder

ICD-9: 309.21 ICD-10 - Separation anxiety disorder of childhood F93.0

Separation anxiety disorder (SAD) occurs mostly in children. Individuals with SAD become excessively afraid of leaving a loved one, usually a parent, and are preoccupied with thoughts that frightening things may happen while they are separated (i.e., they or the attachment figure may die or be injured). In anticipation of separation, the individual is nervous and may cry or cling to the attachment figure. Panic attacks are not uncommon. Occasionally, the individual will hit the person forcing the separation. When separated, individuals with SAD typically experience physical symptoms in addition to the marked anxiety, including headaches, stomachaches, nausea, and vomiting. Consequently, the individual may refuse to go to school or participate in activities outside the home and therefore may become socially withdrawn. Reactions (tantrums) to attachment figures when forced with separation contribute to parental frustration, resentment, and family conflict. Impairments in social and personal functioning are common. Depression, difficulty concentrating, and sleep problems may be experienced.

Classification (Separation anxiety disorder)

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