ANXIETY DISORDERS

Anxiety disorders tend to be chronic, recurring conditions that vary in intensity over time. They affect 5% to 10% of children and adolescents.

Panic disorder is the presence of recurrent, unexpected panic attacks. At least 1 month of persistent worrying about having another panic attack is required to make the diagnosis (Table 17-1). Panic disorder most often begins in adolescence or early adulthood; onset before puberty is significantly less common. The course of illness tends to be chronic with waxing and waning of symptom severity over time.

A panic attack is a sudden onset of intense fear associated with a feeling of impending doom in the absence of real danger. These attacks occur unexpectedly. Characteristic symptoms include shortness of breath, palpitations, chest pain, a choking or smothering sensation, and a fear of losing control or going crazy (Table 17-2). Panic attacks are classified as spontaneous, bound to situations (occur immediately on exposure), and predisposed to situations (attacks occur while at school, but not every time). Triggers can be external (life-threatening situation) or internal (worries about a situation). Situational attacks are common and occur in many patients with other anxiety disorders.

Panic attacks are time-limited and are accompanied by physical symptoms of anxiety. It is common for patients to think that they are about to die of a heart attack. Patients with asthma have a high incidence of panic attacks.

Prevalence rates for panic disorder in pediatric psychiatric clinics range from 0.2% to 10%; rates are similar in all racial groups. The condition is eight times more common in family members of affected individuals than in the general population. This family association increases the likelihood of an early onset. Twin studies suggest a genetic component. Children with separation anxiety disorder seem to be at particular risk for subsequent development of panic disorder. Agoraphobia is present in approximately half of patients with panic disorder.

There are no diagnostic laboratory or neuroimaging studies for panic disorder or any other anxiety disorder, although infusions of sodium lactate and breathing into a paper bag have been used as provocative tests in laboratory settings. Patients experiencing a panic attack may present with respiratory alkalosis (due to hyperventilation). The differential diagnosis for panic disorder includes the other anxiety disorders, especially those secondary to general medical conditions and substance-induced anxiety disorders.

Anxiety disorder due to a general medical condition is characterized by impairing symptoms of anxiety that are judged to be the direct consequence of another medical illness. Medical illnesses that can mimic panic disorder and other anxiety disorders include cardiovascular disease (dysrhythmias, mitral valve prolapse), hyperthyroidism, asthma, irritable bowel syndrome, chronic obstructive pulmonary disease, and pheochromocytoma. Substance-induced anxiety disorder is characterized by symptoms of anxiety that are judged to be the direct consequence of a drug (caffeine or other stimulants). A variety of psychiatric illnesses may occur concurrently with panic disorder, including major depression, obsessive-compulsive disorder (OCD), and other anxiety disorders. Patients with anxiety disorders abuse substances at higher rates than the general population.

Agoraphobia literally means fear of the marketplace. In common usage, the term is applied to a pathologic condition describing fear of situations where escape is difficult or would draw unwanted attention to the person. Agoraphobia is often persistent and can leave people homebound. It can occur independently or in relationship to panic disorder; 95% of patients with agoraphobia also have panic disorder. The condition is more common in females. Consider the diagnosis of a specific phobia (as opposed to agoraphobia) if the avoidance is limited to one or a few specific situations or social phobia if avoidance is limited to social situations in general.

Generalized anxiety disorder (GAD) is characterized by 6 or more months of persistent and excessive anxiety and worry and includes a historical diagnosis of overanxious disorder of childhood. It is common in patients referred to a psychiatrist. The anxiety must be accompanied by at least three of the following symptoms: restlessness, easy fatigability, difficulty concentrating, irritability, muscle tension, and disturbed sleep. The fear or anxiety must be out of proportion to what is realistic. The worries should be multiple, not paroxysmal, and not focused on a single theme, as in separation anxiety disorder (Table 17-3).

The etiology of GAD is unknown. The lifetime prevalence rate is 5%. Biologic relatives have an increased risk of developing GAD and an increased risk of major depression. Physical signs of anxiety are often present, including shakiness, trembling, and myalgias. Gastrointestinal symptoms (nausea, vomiting, diarrhea) and autonomic symptoms (tachycardia, shortness of breath) commonly coexist. In children and adolescents, the specific symptoms of autonomic arousal are less prominent. Symptoms are often related to school performance or sports. Children with GAD are often perfectionists and overly concerned about the approval of others. Patients with GAD describe having been anxious all their lives and have more sleep disturbance than patients with any other kind of anxiety disorder.

There are no laboratory or imaging studies diagnostic for GAD. The differential diagnosis for GAD includes normal anxiety, other anxiety disorders (OCD, separation anxiety disorder, social phobia), anorexia nervosa, somatoform disorders, and major depression. Substance-induced anxiety disorder must also be considered (caffeine, sedative-hypnotic withdrawal). Care must be taken to elicit internalizing symptoms of negative cognitions about the self (hopelessness, helplessness, worthlessness, suicidal ideation), as well as those concerning relationships (embarrassment, self-consciousness) and associated with anxieties. Enquiry about eating, weight, and energy, and interests should also be carried out to eliminate a mood disorder.

Post-traumatic stress disorder (PTSD) is characterized by re-experiencing a traumatic event in which actual or threatened death or serious injury was possible. The re-experiencing is accompanied by avoidance of stimuli that remind the person of the trauma and by autonomic hyperarousal (Table 17-4). Stressors including rape and torture are particularly traumatic. PTSD can result from one dramatic incident (e.g., a motor vehicle accident), but in children it is often the result of repeated trauma and may be more difficult to treat.

Severity, duration, and proximity of the traumatic event are the most likely predictors of PTSD. Dissociative states lasting a few seconds to many hours, in which the person relives the traumatic event, are referred to as flashbacks. Re-experiencing trauma in children may be nonspecific to the trauma (e.g., dreams of monsters). In children, play may revolve repetitively around the circumstances of the trauma. In adolescents, anticipation of unwanted visual imagery increases the risk of irritable mood, anger, and sleep deprivation (sleep is associated with nightmares and undesirable visual experiences). When faced with reminders of the original trauma, physical signs of anxiety or increased arousal, including difficulty falling or staying asleep, hypervigilance, exaggerated startle response, irritability, angry outbursts, and difficulty concentrating, occur.

Most PSTD symptoms are adaptive until they interfere with the person’s functioning. PTSD usually begins within 3 months of the trauma, although delay in symptom expression can occur. Typically, an acute stress disorder is present immediately after the trauma. The risk of chronic PTSD increases when symptoms are unresolved by 6 weeks and there are higher premorbid levels of anxiety or depression. Rates of suicide attempts are threefold higher than unaffected controls. There is an increased risk of PTSD in girls and less able children, especially when there is concurrent experience of death or severe injury to a member of close family. There is an increased risk of developing PTSD in family members of patients with PTSD. The lifetime prevalence estimates of PTSD vary, but 8% is most commonly cited (11.5% in children from war zones).

The differential diagnosis of PTSD includes other anxiety disorders, adjustment disorders, acute stress disorder, OCD, psychotic disorders, substance-induced disorders, and psychotic disorders secondary to general medical conditions. Although rare, if financial compensation is at issue, malingering should be ruled out.

The prognosis for people with PTSD varies. Some patients have excellent recovery, and others have significant functional decline. Early intervention to decrease morbidity is important. There is no proven primary prevention for PTSD.

For PTSD, antidepressants may be augmented by clonidine (also useful in hyperarousal and impulsivity) in the presence of severe affective dyscontrol. Atypical antipsychotics are used if self-injurious behavior, dissociation, psychosis, and aggression are present. Atomoxetine is useful in PTSD with concurrent ADHD. Asking children to draw on their experience often assists recall of both the event and the associated emotion. It is important to ensure that re-experiencing the event results in mastery of the associated distress and diminishes personal impairment, rather than increasing it by magnifying the impact of the original trauma. Critical-incident stress debriefing soon after the event greatly reduces distress and involves discussing the nature and impact of the trauma event in a group format.

Acute stress disorder is characterized by the same signs and symptoms as PTSD but occurs immediately after a traumatic event. These symptoms do not always progress to PTSD. If impaired function persists after 1 month, the diagnosis is PTSD.

Anxiety disorder not otherwise specified is a common condition in clinical practice. This diagnosis is used when there is impairing anxiety or phobic symptoms that do not meet full criteria for another anxiety disorder.

School phobia and separation anxiety disorder (SAD) are often intertwined. Children and adolescents who avoid or refuse to go to school may have histories of separation anxiety and vague somatic complaints (e.g., headaches, abdominal pain, fatigue). They often have been seen by numerous specialists and have undergone elaborate medical evaluations. Their absence from school often is mistakenly seen as a consequence of their symptoms.

SAD occurs in 2% to 4% of children and adolescents. It is most often seen in prepubertal children, with proximity-seeking clinging behavior as a common presenting complaint. There is no marked sex difference. The expression of the somatic symptoms is a means to avoid school and gain parental attention. Patients may have a valid or an irrational concern about a parent or have had an unpleasant experience in school. The prospect of returning to school provokes extreme anxiety and escalating symptoms. True phobia related to schoolwork is rare. School phobia that first presents during adolescence may be an expression of a severe underlying psychopathologic condition, and psychiatric consultation is needed. SAD is a strong (78%) risk factor for developing problems in adulthood, such as panic disorder, agoraphobia, and depression. The most effective treatment is for the child to return to school (or the exposure).

In the management of anxiety disorders, likely medical conditions, including hyperthyroidism, medication side effects, substance abuse, or other medical conditions, should be ruled out. The patient should be screened for comorbid psychiatric disorders, such as mood disorders, psychosis, eating disorders, tic disorders, and disruptive behavior disorders. A history from multiple sources is important, because the child may be unable to effectively communicate symptoms. A detailed history that includes the nature of the anxiety triggers; psychosocial history; and family history of tics, anxiety disorders, depression, and other mood disorders should be taken. The younger child may communicate his or her anxieties better through drawings or play.

Combined pharmacologic and psychotherapy is better than either alone for the treatment for all anxiety disorders. Selective serotonin reuptake inhibitors (SSRIs) are the medication of choice. The SSRIs approved for children by the U.S. Food and Drug Administration are fluoxetine, sertraline, and fluvoxamine. They can initially exacerbate anxiety or even panic symptoms. Clomipramine requires electrocardiographic and blood level monitoring but may be effective, and it is approved by the U.S. Food and Drug Administration for OCD. Benzodiazepines include a risk of causing disinhibition in children. Alpha-2a-agonists (guanfacine and clonidine) may be useful if autonomic symptoms are present. Anticonvulsant agents (gabapentin, topiramate, and oxcarbazepine) are used when other agents are ineffective. Co-occurrence of the inattentive type of ADHD and an anxiety disorder is common. When using a stimulant, it is advisable to start at a low dose, increasing slowly to minimize the risk of increasing anxiety. Patients with anxiety disorders are often less tolerant of medication side effects. Extra support helps them maintain treatment regimens.

Cognitive and behavioral therapy can be beneficial in a variety of anxiety disorders. For mild to moderate anxiety, evidence-based psychotherapies and psychoeducation should be used first. Reassurance that the patient does not have a life-threatening illness is important. Other psychosocial treatments include stress management, supportive therapies, and biofeedback. Panic disorder tends to be chronic but usually is responsive to treatment. Emphasis is placed on decreasing morbidity through proper treatment. There are no proven primary prevention techniques.

SPECIFIC PHOBIAS

Specific phobias are marked persistent fears of things or situations, which often lead to avoidance behaviors (Table 17-5). The associated anxiety is almost always felt immediately when the person is confronted with the feared object or situation. The greater the proximity or the more difficult it is to escape, the higher the anxiety. Many patients have had actual fearful experiences with the object or situation (traumatic event). The response to the fear can range from limited symptoms of anxiety to full panic attacks. Although adults and adolescents usually can recognize that their fears are out of proportion to the circumstances, children may not. Children may express their anxiety as crying, tantrums, freezing, or clinging.

Phobia prevalence rates in children and adolescents are estimated at about 2%. The ratio of females to males is 2:1. There is an increased risk of specific phobias in first-degree relatives of patients with specific phobias. Comorbidity with other anxiety disorders is high. Adults with panic and agoraphobia usually have a childhood history of simple phobias, suggesting that some childhood phobias persist over time.

School phobia is one of a range of reasons for school nonattendance. In severely worried children, defensive aggression may be used to prevent attendance. Otherwise, these patients do not have antisocial tendencies. Boys and girls are equally affected and there is no association with social class, intelligence, or academic ability. The youngest in a family of several children is more likely to be affected as well as children of older parents. Truancy is generally associated with older adolescents with lower levels of fear. Unlike anxious school refusers, truants hide their school nonattendance from their parents.

Social phobia is a common (3% to 13% prevalence) type of phobia characterized by a marked and persistent fear of social or performance situations in which embarrassment might occur (Table 17-6). In other ways, social phobia is similar to specific phobias. There is a wariness of strangers and social apprehension or anxiety when encountering new, strange, or socially threatening situations. Children appear to have a lower rate of negative cognitions (e.g., embarrassment, overconcern, self-consciousness) than adults. Children with simple avoidant disorders are younger than those with more socialized phobic conditions. Left untreated or poorly treated, phobias can become immobilizing and result in significant morbidity. People with specific phobias often significantly restrict their lives. A vasovagal fainting response is common in blood/injection/injury-type phobias. In addition, blood/injection/injury-type phobias may lead patients to avoid needed medical care.

No laboratory or imaging studies can diagnose a specific phobia. Specific phobias share many symptoms with other anxiety disorders. Concurrent illnesses often include major depression and substance-related disorders; 60% of patients with a specific phobia meet diagnostic criteria for another psychiatric disorder. The diagnosis requires that anticipation of fear or actual fear must interfere with the child’s daily living.

Cognitive and behavioral techniques are frequently successful in the treatment of phobias. Common techniques include rapid exposure (flooding) or systematic desensitization (slowly getting closer to the feared object). SSRIs or buspirone are used in more extreme or urgent cases. The psychotherapeutic techniques are more likely to have persistent effects than medications. If a phobia persists into adulthood, there is only a 20% chance of full remission. There are no well-studied primary prevention techniques. Preventing a cycle of exposure and escape (which reinforces the phobic response) can decrease the likelihood of prolonged impairment.