Abstract
Dizziness and vertigo are infrequent complaints in the adolescent population. For those few adolescents who seek outpatient evaluation for these complaints, the majority are diagnosed with migraine headaches, and most meet criteria for the diagnosis of vestibular migraines and/or probable vestibular migraine according to the International Classification of Headache Disorders, third edition (beta version). In addition to migraine headache, the differential diagnosis in this age group includes episodic ataxia type II; chronic daily headaches; postural orthostatic tachycardia; intracranial mass lesions; psychiatric disorders (e.g., depression or somatoform disorders); and rarely vestibular disorders, including viral labyrinthitis and Meniere’s disease. Evaluation and, in the majority of cases, diagnosis are based on careful history and physical examination with neuroimaging performed for all adolescents with a history of trauma, an abnormal neurologic examination, persistent headaches, or an indication of central lesion on vestibular testing.
Keywords
Adolescence, Brain development, Chronic daily headache, Dizziness, Episodic ataxia, Migraine, POTS, Vertigo
The Adolescent Brain
Adolescence, the developmental transition between the dependency of childhood and the independency of adulthood, encompasses the approximate period between 12 and 18 years of age. Behavior during this developmental stage is frequently characterized by risk taking, impulsivity, and poor choices. The indestructible attitude of the adolescent, which can be met by negative consequences, promotes experimentation of adult practices, development of self-esteem, and eventually social acceptance.
Although the brain reaches 90% of its adult size by 6 years of age, pruning (resulting in decreasing synaptic density) and cortical thinning occur throughout childhood and adolescence. The volume of white matter continues to increase until approximately 20 years of age and is the result of ongoing myelination of white matter tracts. One of the last regions to undergo maturational processes is the prefrontal cortex, the region of the brain that participates in executive, attentional, and regulatory functions.
Adolescence represents a unique period of brain development marked by changes in neuroconnectivity and functional activation. Casey and colleagues suggested that the differential developmental trajectories of the limbic system and subcortical structures (e.g., basal ganglia) as compared with the prefrontal cortex could, in part, explain the impulsivity and risk-taking behavior that occur during adolescence. In their model, earlier maturation of the limbic system and subcortical structures during adolescence drives the adolescent behavior. As connections of the prefrontal cortex mature, influence of the limbic system and subcortical structures is reduced and the prefrontal cortex dominates, resulting in improved ability to suppress impulses and greater emphasis on goal-driven choices. Their model is supported by recent demonstrations of an exaggerated response of the nucleus accumbens in the adolescent as compared with the adult and child in a task that manipulated reward values, and correlation of the development of fiber tracts between the prefrontal cortex and basal ganglia with performance on a go/no-go task, a measure of inhibitory control.
Vertigo represents the sensation of inappropriate or abnormal motion and can be related to dysfunction of the vestibular system. Although morphologic development of the vestibular system is complete by term gestation, studies of the development of postural balance suggest that functional maturation of the vestibular system is ongoing during childhood and adolescence (see Chapter 3 ). For example, Steindl and colleagues used the sensory organization subtest of computerized dynamic posturography to measure postural stability in 140 children aged 3.5–16 years without known peripheral or central vestibular, proprioceptive, or visual disorders or medications that could affect balance. They observed increasing maturation of the vestibular afferent system up to 16 years of age. Their findings were in contrast to those of a prior study suggesting that vestibular development was not complete by 16 years of age. However, Steindl and colleagues observed reduced vestibular influence on postural control in adults as compared with the 15- to 16-year-old age groups. Cumberworth and colleagues suggested that the late functional development of the vestibular system as compared with the somatosensory and visual control of balance may explain differential rates of motion sickness in children and adolescents as compared with adults.
Vertigo and Dizziness in the Adolescent
Vertigo and dizziness are not synonymous terms, although they are often used interchangeably. Individuals with vertigo will often describe a rotational or room-spinning sensation. They may feel as though they are on a carousel or bobbing in a boat. Nausea and vomiting are often associated complaints. True vertigo implies an equilibrium disturbance associated with dysfunction of either the central or peripheral vestibular system. In contrast, dizziness is a term that may be used by patients to describe a distorted perception of the environment associated with etiologies that range from true vertigo to imbalance to presyncope to somatoform disorders. The majority of adults who presented to emergency departments (EDs) in the United States between 1993 and 2005 with a chief complaint of dizziness did not have a vestibular disorder and ultimately were diagnosed with cardiovascular, neurologic, or metabolic/toxic illnesses.
Complaints of dizziness and vertigo are common in the general population, occurring more frequently in women and those older than 60 years. In a review of National Hospital Ambulatory Medical Care Survey data of persons who presented to the ED with a chief complaint of vertigo/dizziness or the final diagnosis of a vestibular disorder, 16- to 19-year-old patients represented the smallest fraction. More recently, Li and colleagues used data from the 2012 National Health Interview Survey, which included a total of 10,954 children to study the prevalence of dizziness and balance problems in children aged 3–17 years (mean = 10.2 years) and found that the overall prevalence for the year analyzed was 5.3%, with a higher incidence in children aged 12–17 years (6.8%). When further classified, vertigo prevalence was 2.8% for adolescents (twice that of younger children), whereas the prevalence of lightheadedness was 3.7%. These authors noted a consistent age-related increase in the prevalence of dizziness and balance problems.
In contrast, population-based studies suggest that episodic vertigo and dizziness may be more common during adolescence than initially proposed. Russell and Abu-Arafeh provided a screening questionnaire to 2165 children ranging in age from 5 to 15 years who attended school in the city of Aberdeen, Scotland. Of the children surveyed, 314 (14%) reported at least one episode of dizziness in the previous year and 92 children (4%) reported three or more episodes of dizziness. Although complaints of dizziness occurred at all ages in this study, it was more common in adolescents, with a peak onset at 12 years of age. In contrast, Niemensivu and colleagues, based on prospective polling of children and adolescents ranging in age from 1 to 15 years, found that 8% (75 of 938) experienced an episode of vertigo or dizziness at some point during their life, predominantly between 11 and 15 years of age. These studies and future studies that attempt to define the true prevalence of vertigo and dizziness during childhood and adolescence have many potentially confounding variables: young children and adolescents may have difficulty accurately describing their symptoms; dizziness often resolves quickly in children and thus may be disregarded by the child or their family; and vertigo or dizziness may be reported by the adolescent or family as clumsiness. Furthermore, extrapolating findings in different populations may be difficult as prevalence may be influenced by environmental and genetic factors.
Vertigo and dizziness during adolescence can be the presenting symptom or, more typically, can be part of a complex of symptoms in a wide range of disorders that includes viral illnesses and intracranial tumors (see Box 6.1 ). In a hospital-based study, Fried reviewed medical records of all admissions to the Boston City Hospital for the 12-month period that spanned July 1976 to June 1977. The majority of adolescents admitted for dizziness during this period had experienced a concussion (4 of 9). This was also a common cause for dizziness and balance problems as reported by Li and colleagues.
Most Common
Migraine
Migraine equivalent with benign paroxysmal vertigo of childhood being much more common in children than adolescents
Psychogenic
Viral infections or otitis media
Common
Chronic daily headache
Trauma
Postural orthostatic tachycardia syndrome
Less Common
Intracranial tumor
Epilepsy
Benign paroxysmal positional vertigo
Vestibular neuritis
Demyelinating disease
In contrast, retrospective reviews of outpatient medical records of adolescents evaluated in either neurology or otolaryngology clinics consistently report vestibular migraine and benign paroxysmal vertigo of childhood (BPVC) as the most common causes of vertigo and dizziness in adolescents and children. For example, Weisleder and Fife reviewed charts of 31 children and adolescents ranging in age from 6 to 17 years who were referred for vestibular testing at a tertiary care center over a 6-year period. The majority of patients ( n = 11; 35%) were diagnosed with vestibular migraine. Other diagnoses included BPVC ( n = 6; 20%), anxiety attacks ( n = 3; 10%), Meniere’s disease ( n = 2), idiopathic sudden-onset sensorineural hearing loss ( n = 1), familial vertigo/ataxia syndrome (episodic ataxia type II, n = 1), and malingering ( n = 1).
In addition to vestibular migraine, these clinic-based studies have consistently observed a high incidence of depression and somatoform disorders among children and adolescents evaluated in these specialty clinics for complaints of vertigo or dizziness. For example, Ketola and colleagues reported that psychogenic vertigo accounted for 8% (9 of 119) of children and adolescents with the chief complaint of vertigo who were evaluated at the Otolaryngologic Clinic of Helsinki University Central Hospital between the years 2000 and 2004. Following psychiatric consultation, three children (aged 10 to almost 13 years) were diagnosed with depression; one adolescent (age 13.5 years) was diagnosed with a combination of conversion disorder, hyperventilation, and depression; one adolescent (age 15.6 years) was diagnosed with psychotic episode and depression; and the other four children (aged 9–11 years) were diagnosed with psychogenic headache, obsessive-compulsive disorder, panic disorder, or conversion disorder. Compared with children and adolescents who were identified as having an organic cause for vertigo, this group of children and adolescents had more frequent attacks or a complaint of constant vertigo, were more likely to suffer from school absenteeism, and were more likely to have dysfunctional relationships at school or at home. In addition, Emiroglu and colleagues found that 29 of 31 patients (93.5%) who presented to a pediatric neurology clinic for complaints of dizziness, headache, or fainting met criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) for a psychiatric comorbidity, even when the primary diagnosis was some type of migraine headache.
Not all adolescents complaining of vertigo and dizziness will be referred for specialty clinic evaluation; therefore, many causes of dizziness in the adolescent are likely to be underreported in neurology and otolaryngology clinic-based studies. For example, complaints of vertigo or dizziness in the setting of concussion are likely to be principally managed by the pediatrician ; the child with dizziness in the setting of syncope or presyncope may be managed by the pediatrician or is more likely to be referred to a cardiologist than to a neurologist or to an otolaryngologist for further management; and the child with a brain tumor is most likely to be diagnosed in the ED and be managed by the oncologist, neuro-oncologist, and/or the neurosurgeon.
Diagnosis and Treatment of Specific Causes of Vertigo in the Adolescent
Migraine
Approximately 30% of adolescent girls experience migraine headaches, and along with variants, migraines are the most common episodic disorder of childhood with an estimated incidence of 5%–15%. Migraine and BPVC, considered by many to be a migraine variant in younger children, account for 50%–75% of children who present to specialty clinics with vertigo and a normal otologic examination. Migraine frequency increases and BPVC frequency decreases with age.
The vertigo associated with migraine may precede the headache (aura), may be part of the headache itself, or may not be temporally related to the headache in up to 60% of individuals. Lee et al. conducted a multicenter study of all pediatric patients (aged 0–18 years; average age 12.9 years) admitted for dizziness in 11 hospitals in Korea. They found a total of 411 children aged 13–17 years who reported symptoms of vertigo and/or balance problems. Sixty percent of these patients were adolescents ( n = 247), and approximately thirty percent of the children in this age group met criteria for vestibular migraine ( n = 75) according to the International Classification of Headache Disorders third edition, beta version (ICHD-3 beta; see Box 6.2 ). Similarly, in a 5-year retrospective study specifically looking at vestibular migraine in patients 3–18 years of age referred to the German Center for Vertigo and Balance Disorders ( n = 118), Langhagen et al. found that 30% of these patients met ICHD-3 beta diagnostic criteria, with 28% of patients classified as probable vestibular migraine, and 6% classified as suspected vestibular migraine. The incidence of definite vestibular migraine was higher in girls (31%) as compared with boys (29%), and up to 73% of patients reported headaches in all or some of their vertigo attacks. In this study, 51% of patients reported motion sickness and 65% had a positive family history of migraine headaches. Interestingly, somatoform vertigo co-occurred in 27% of patients, similar to what was reported by Batu and colleagues in a Turkish study.
Diagnostic Criteria for Vestibular Migraine
- 1.
At least five episodes fulfilling criteria (3) and (4)
- 2.
Current or past history of migraine (without or with aura)
- 3.
Vestibular symptoms of moderate or severe intensity for 5–72 hours
- 4.
At least 50% of episodes associated with at least one of the following
- a.
Headache with at least two of the following: unilateral headache, pulsating quality, moderate-severe intensity, aggravation by routine physical activity
- b.
Photophobia and phonophobia
- c.
Visual aura
- a.
- 5.
Not better accounted for by any other ICHD-3 diagnosis or any other vestibular disorder
Criteria for Probable Vestibular Migraine
- 1.
At least five episodes with vestibular symptoms of moderate or severe intensity for 5–72 hours
- 2.
Only one criteria for (2) and (4) as above
- 3.
Not better accounted for by any other ICHD-3 diagnosis or any other vestibular disorder
Furthermore, vertigo is a well-established manifestation of basilar migraine, which also has associated symptoms of ataxia, dysarthria, tinnitus, and visual changes. The vertigo associated with these headaches is often brief and frequently accompanied by nausea and vomiting.
The pathophysiology of vertigo in migraines is poorly understood. Unilateral neuronal instability of the peripheral vestibular nerve, idiopathic asymmetric activation of brainstem vestibular nuclei, and vasospasm causing transient ischemia of the labyrinth or central vestibular pathways have all been suggested. Vestibular laboratory testing is often abnormal and demonstrates central findings in adults and children with basilar migraines, even between attacks.
Before making the diagnosis of migraine headache in the adolescent being evaluated for complaints of headache and vertigo, episodic ataxia type 2 (EA-2; previously known as familial cerebellar ataxia without myokymia, hereditary paroxysmal cerebellar ataxia, periodic vestibulocerebellar ataxia, and acetazolamide-responsive episodic ataxia) should be considered. This rare autosomal dominant disorder is the result of a spectrum of mutations that affect CACNA1A , the gene that encodes the α-1A subunit of P/Q type calcium channels (Cav2.1) located on chromosome 19p. Missense mutations of this same gene are linked to familial hemiplegic migraine, and a CAG expansion of exon 47 has been linked to spinocerebellar ataxia type 6. EA-2 is characterized by episodic attacks that last from hours to days and can be precipitated by stress or exercise as well as caffeine and alcohol. Many features of the attack can overlap those of migraine: headache, which is typically occipital in location, vertigo, nausea, and vomiting. Indeed, most people with EA-2 also meet ICHD-3 diagnostic criteria for migraine. Distinguishing features during the attack are the presence of concurrent ataxia and nystagmus as well as the strong family history consistent with autosomal dominant inheritance. During the attack, dysarthria, diplopia, tinnitus, dystonia, and hemiplegia may also be present. Onset is typically before 20 years of age with a range from 2 to 61 years. Of interest, a large percentage of individuals with EA-2 develop ataxia and nystagmus in the interictal periods, and atrophy of the cerebellar vermis has been observed on MRI. An important reason to recognize this syndrome early is that acetazolamide has been shown to be effective in reducing the frequency of attacks that are typically rare but have been reported as often as four times per week.
Treatment of migraine headache is divided into abortive and prophylactic therapies. For those with vertigo as the manifestation of their migraine without significant headache, management with antimotion sickness medications, such as scopolamine, has been proposed to provide symptomatic relief. Unfortunately, randomized controlled studies looking at therapeutic interventions specifically focusing on vestibular migraines are limited in the adult population and nonexistent in the pediatric population. Most specialists will focus on treating these as migraine headache variants, and triptans and nonsteroidals are generally used as first-line treatment. The American Academy of Neurology (AAN) guidelines for acute treatment of migraines in children and adolescents report level A evidence for nasal sumatriptan. In patients who do not respond to nasal sumatriptan, consideration for other triptans (zolmitriptan) has been reported to be useful in small study groups in a handful of patients ; nonsteroidals and indomethacin should be used in place of medications with caffeine, barbiturates, or opiates, as the former are less likely to cause dependency and medication overuse headache. Dihydroergotamine, intravenous valproate, or steroids have also been used for abortive treatment of severe migraine headaches that have not responded to other outpatient treatments.
If the migraines are frequent or disabling (i.e., affecting school performance and/or school attendance) a prophylactic agent should be considered. Nevertheless, it is important to recognize that in pediatric patients, the rate of placebo response can be as high as 25%. Cognitive behavioral therapy (CBT) has been shown to be of extreme value with the added benefit of having no side effects. Calcium channel blockers, β-blockers, antiepileptics, such as topiramate and valproate, or tricyclic antidepressants (e.g., amitriptyline) have shown some level of prophylactic efficacy in small studies, although AAN guidelines report insufficient evidence to make formal recommendations for the adolescent. This is further supported by a recent study of amitriptyline versus topiramate versus placebo in adolescents with episodic migraine, which was terminated early because of futility. In their multicenter double-blind study, Powers and colleagues found no difference in primary outcomes, while patients in either arm of pharmacologic treatment experienced increased risk for side effects. When prophylactic treatment is considered, 1 month at a therapeutic dose, if tolerated, should be attempted before altering therapy. Lifestyle changes, including sleep hygiene, regular exercise, a balanced diet, and adequate hydration are crucial, as is early CBT.
Chronic Daily Headaches
In contrast to people with migraine headaches who will often describe true vertigo, a more general sense of dizziness is a common complaint of adolescents with chronic daily headache. Chronic daily headaches are defined as headaches lasting longer than 4 hours per day, for more than 15 days per month, for 3 months or more, without underlying pathology. Prevalence studies estimate that 2%–4% of adolescent girls and 0.8%–2.0% of adolescent boys suffer from chronic daily headaches. A study by Mack reports that 75% of these patients have a history of episodic migraines, and the other 25% have had a recent viral illness or minor head trauma. Diffuse weakness, unsteadiness, and visual changes, frequently characterized as blurry vision in both eyes, are common associated symptoms. The dizziness often worsens with changes in position, especially when getting out of bed in the morning, and syncope or near syncope can occur. Mood disorders are almost universally present in adolescents who have chronic daily headaches, and treating one may not always alleviate the other (i.e., treatments for chronic daily headaches likely will not work while the mood disorder remains untreated).
Indeed, chronic daily headaches are often more difficult to treat than episodic migraine headaches and may take weeks to months to improve. Comorbidities, such as sleep disturbances, mood disorders, and medication overuse, make them even more challenging. Patient (and parent) frustrations are common and can be confounding.
As with migraine headache, treatment of chronic daily headache is also divided between abortive and prophylactic medications, with less evidence of efficacy in the adolescent population. Amitriptyline has demonstrated safety and efficacy as a prophylactic agent in the treatment of chronic daily headache in children, although higher doses may be needed than those for migraine prevention. Amitriptyline is also helpful in improving sleep onset, which is a common comorbidity. Cardiac side effects (e.g., prolongation of the QT interval), weight gain, and sedation should be closely monitored. Fluoxetine is the only selective serotonin reuptake inhibitor approved for the treatment of mood disorders in children and may be an effective prophylactic treatment for chronic daily headache. However, there is an increased risk of suicidal thoughts and suicide attempts in adolescents who take this medication. Caution should be used when fluoxetine is combined with tricyclics, as these medications are metabolized through the same pathways, which leads to higher drug levels and more serious side effects, including the risk of serotonin syndrome.
Nonpharmacologic methods should be included in treatment of migraine headache and chronic daily headache. Headache diaries are invaluable to help track patterns, foods, or activities that may cause or be associated with headache. Psychological consultation for CBT and treatment of underlying mood disorders and physical therapy evaluation for reintroduction of physical activity are helpful adjunctive treatments. Awareness of seasonal variations and effects on school performance also need to be addressed.
Postural Orthostatic Tachycardia Syndrome
Although postural orthostatic tachycardia syndrome (POTS) was not identified as a common cause of vertigo or dizziness in the specialty clinic-based studies previously cited, the majority of persons with POTS do complain of dizziness. Patients with POTS have orthostatic intolerance defined by an increase in heart rate (HR) of more than 40 bpm (30 bpm in adults) within 10 minutes of standing from supine position without orthostatic fall in blood pressure. Young women and women of childbearing age are mainly affected (5:1 ratio). The syndrome is rarely seen in young children.
POTS is characterized by a constellation of symptoms, including dizziness, headache, and fatigue, as well as nausea, “mental fog,” palpitations, diaphoresis, tachypnea, and diffuse weakness that occur on standing and are relieved by sitting or lying down. Most patients will report that their symptoms are debilitating and incapacitating. Patients with POTS also complain of difficulty with sleep, depression, and anxiety, but these symptoms are usually not directly related to POTS. Precipitating factors include standing, physical activity, and heat.
Onset is often in the early teen years, can be preceded by viral illness, and may have a monophasic or relapsing-remitting course. Adolescents within 1–3 years of their growth spurt, who are unable to return to normal activity after suffering a minor illness or injury that may be prolonged and lead to a period of immobility, seem susceptible to POTS. When they attempt to return to normal activity, they become symptomatic when trying to stand upright.
Diagnosis is based on a thorough history and a normal neurologic examination and can be confirmed while triggering an event in the clinic. HR and blood pressure should be recorded at rest while lying down for 10 minutes, and vital signs be reassessed on standing at 1, 3, 5, and 10 minutes. An increase in the HR fulfilling criteria at any time point during the 10-minute evaluation in the absence of any other causes for vertigo is diagnostic of the syndrome. A small number of patients can have significant flushing as part of the syndrome, making the diagnosis of mast cell activation disorder a consideration.
POTS is seen more frequently in patients with hyperextensible joints and cellular matrix protein disorders (e.g., Ehlers-Danlos), suggesting an abnormality in smooth muscle response to the autonomic nervous system. The coincidence with puberty in adolescent girls suggests a hormonal influence, and at least one gene mutation in norepinephrine transport protein deficiency also implicates a genetic component. Approximately 50% of patients with POTS experience a viral infection weeks to a few months before the onset of symptoms, with as many as 30% experiencing syncopal episodes. Fatigue is a frequent comorbidity in patients with POTS, with more than 90% of patients reporting the symptom and approximately 64% of patients meeting criteria for chronic fatigue syndrome. In a handful of studies, chronic infections with viruses such as Epstein-Barr virus and enterovirus have been proposed as triggering events, and antibodies to ganglionic acetylcholine receptors and α-1 adrenergic receptors suggest an autoimmune cause. However, the direct mechanism by which these patients develop symptoms is still not fully understood. As mentioned previously, many patients complain of mental fog. It is unclear whether this lack of focus is a result of chronic fatigue or is part of the syndrome, as the underlying mechanisms to explain the cognitive symptoms are still not well understood.
Different mechanisms for POTS have been proposed, and most likely a combination of these is responsible for development of the syndrome (see Table 6.1 ). Proposed mechanisms are related to improper interactions between carotid baroreceptors and chemoreceptors leading to reduced blood flow to the brain and the brain’s ability to cope with physiologic changes needed to sustain adequate perfusion (see Chapter 15 ). In general, when changing from a supine or sitting position to standing, there is an immediate decrease in venous return to the heart from the downward shift of blood in the legs. Under normal physiology, this is compensated for by an increase in HR and blood pressure. Blood is then redistributed to the vital organs by splanchnic and peripheral vasoconstriction, leading to normalization of blood distribution and therefore HR and blood pressure. Patients who suffer from POTS, however, are not able to achieve adequate venous return despite physiologic increases in HR. Therefore, their HR continues to increase without the appropriate elevation in blood pressure.
