Comorbidities in vestibular migraine

A growing body of clinical and epidemiological evidence supports a specific relationship between vestibular symptoms and migraine. Without a biomarker or complete understanding of pathophysiology, diagnosis of vestibular migraine (VM) currently depends upon symptoms in two dimensions: episodic vestibular symptoms temporally related to migraine symptoms. The Bárány Society and the International Headache Society have recently developed consensus diagnostic criteria. However, many issues remain unsettled, including the type, duration, and timing of vestibular symptoms related to headache that should be required for diagnosing VM. This paper focuses on the challenging third dimension of comorbidity, a frequent cause of diagnostic uncertainty that may confound clinical application and research validation of VM criteria. Several other neurotologic conditions occur more frequently in migraineurs than controls, including benign paroxysmal positional vertigo, Ménière's disease, and motion sickness. Patients with VM also have high rates of chronic subjective dizziness, which may be associated with anxious, introverted temperaments that can affect clinical presentation and treatment response. Broadly inclusive studies of well-characterized patients with other neurotologic and psychiatric comorbidities are needed to fully understand how vestibular symptoms and migraine interact in order to truly validate vestibular migraine, distill its essential features, define its boundaries, and characterize overlapping comorbidities.

Role of the Insula and Vestibular System in Patients with Chronic Subjective Dizziness: An fMRI Study Using Sound-Evoked Vestibular Stimulation

Chronic subjective dizziness (CSD) is a common vestibular disorder characterized by persistent non-vertiginous dizziness, unsteadiness, and heightened sensitivity to motion stimuli that may last for months to years after events that cause acute vestibular symptoms or disrupt balance. CSD is not associated with abnormalities of basic vestibular or oculomotor reflexes. Rather, it is thought to arise from persistent use of high-threat postural control strategies and greater reliance on visual cues for spatial orientation (i.e., visual dependence), long after triggering events resolve. Anxiety-related personality traits confer vulnerability to CSD. Anomalous interactions between the central vestibular system and neural structures related to anxiety may sustain it. Vestibular- and anxiety-related processes overlap in the brain, particularly in the insula and hippocampus. Alterations in activity and connectivity in these brain regions in response to vestibular stimuli may be the neural basis of CSD. We examined this hypothesis by comparing brain activity from 18 patients with CSD and 18 healthy controls measured by functional magnetic resonance imaging during loud short tone bursts, which are auditory stimuli that evoke robust vestibular responses. Relative to controls, patients with CSD showed reduced activations to sound-evoked vestibular stimulation in the parieto-insular vestibular cortex (PIVC) including the posterior insula, and in the anterior insula, inferior frontal gyrus, hippocampus, and anterior cingulate cortex. Patients with CSD also showed altered connectivity between the anterior insula and PIVC, anterior insula and middle occipital cortex, hippocampus and PIVC, and anterior cingulate cortex and PIVC. We conclude that reduced activation in PIVC, hippocampus, anterior insula, inferior frontal gyrus, and anterior cingulate cortex, as well as connectivity changes among these regions, may be linked to long-term vestibular symptoms in patients with CSD. Furthermore, altered connectivity between the anterior insula and middle occipital cortex may underlie the greater reliance on visual cues for spatial orientation in CSD patients relative to controls.

Medical and Psychiatric Causes of Episodic Vestibular Symptoms

Dizziness and vertigo are among the most common presenting patient complaints in ambulatory settings. Specific vestibular causes are often not immediately identifiable. The first task of the clinician is to attempt to rule in specific vestibular disorders, such as benign paroxysmal positional vertigo through physical examination, diagnostic testing, and history taking. A large proportion of patients with dizziness and vertigo will not be easily classified or confirmed as having a specific vestibular cause. As with any undifferentiated patient, the focus in this setting is to attempt to exclude serious or threatening causes.

Long-term dizziness handicap in patients with vestibular schwannoma: a multicenter cross-sectional study

OBJECTIVE

(1) To characterize long-term dizziness following observation, microsurgery, and stereotactic radiosurgery (SRS) for small to medium-sized vestibular schwannoma (VS) using a validated self-assessment inventory; and (2) to identify clinical variables associated with long-term dizziness handicap.

STUDY DESIGN

Cross-sectional observational study.

SETTING

Two independent tertiary academic referral centers: one located in the United States and one in Norway.

SUBJECTS AND METHODS

All patients with sporadic VS of less than 3 cm who underwent primary microsurgery, SRS, or observation between 1998 and 2008 were identified. Subjects were surveyed via a postal questionnaire using the Dizziness Handicap Inventory (DHI) and a VS symptom questionnaire.

RESULTS

The overall survey response rate was 79%. A total of 538 respondents (mean age, 64 years; 56% female) were analyzed, and the mean time interval between treatment and survey was 7.7 years. Pretreatment variables associated with greater dizziness handicap included female sex, older age, larger tumor size, preexisting diagnosis of headache or migraine, and symptoms of dizziness predating treatment. Significant posttreatment features strongly associated with poor long-term DHI scores included frequency and severity of ongoing headache. On multivariable analysis, treatment modality did not influence long-term dizziness handicap.

CONCLUSION

At a mean of approximately 8 years following treatment, over half of patients with VS reported ongoing dizziness. The authors have identified several baseline features that may help predict the risk of lasting dizziness. Treatment modality does not appear to influence long-term DHI score. We found a strong association between posttreatment headache and poor dizziness handicap. Future study is needed to further define this relationship.

Visual dependency and dizziness after vestibular neuritis

Symptomatic recovery after acute vestibular neuritis (VN) is variable, with around 50% of patients reporting long term vestibular symptoms; hence, it is essential to identify factors related to poor clinical outcome. Here we investigated whether excessive reliance on visual input for spatial orientation (visual dependence) was associated with long term vestibular symptoms following acute VN. Twenty-eight patients with VN and 25 normal control subjects were included. Patients were enrolled at least 6 months after acute illness. Recovery status was not a criterion for study entry, allowing recruitment of patients with a full range of persistent symptoms. We measured visual dependence with a laptop-based Rod-and-Disk Test and severity of symptoms with the Dizziness Handicap Inventory (DHI). The third of patients showing the worst clinical outcomes (mean DHI score 36-80) had significantly greater visual dependence than normal subjects (6.35° error vs. 3.39° respectively, p = 0.03). Asymptomatic patients and those with minor residual symptoms did not differ from controls. Visual dependence was associated with high levels of persistent vestibular symptoms after acute VN. Over-reliance on visual information for spatial orientation is one characteristic of poorly recovered vestibular neuritis patients. The finding may be clinically useful given that visual dependence may be modified through rehabilitation desensitization techniques.

Anxious, introverted personality traits in patients with chronic subjective dizziness

OBJECTIVES

Chronic subjective dizziness (CSD) is a neurotologic disorder of persistent non-vertiginous dizziness, unsteadiness, and hypersensitivity to one's own motion or exposure to complex visual stimuli. CSD usually follows acute attacks of vertigo or dizziness and is thought to arise from patients' failure to re-establish normal locomotor control strategies after resolution of acute vestibular symptoms. Pre-existing anxiety or anxiety diathesis may be risk factors for CSD. This study tested the hypothesis that patients with CSD are more likely than individuals with other chronic neurotologic illnesses to possess anxious, introverted personality traits.

METHODS

Data were abstracted retrospectively from medical records of 40 patients who underwent multidisciplinary neurotology evaluations for chronic dizziness. Twenty-four subjects had CSD. Sixteen had chronic medical conditions other than CSD plus co-existing anxiety disorders. Group differences in demographics, Dizziness Handicap Inventory (DHI) scores, Hospital Anxiety and Depression Scale (HADS) scores, DSM-IV diagnoses, personality traits measured with the NEO Personality Inventory - Revised (NEO-PI-R), and temperaments composed of NEO-PI-R facets were examined.

RESULTS

There were no differences between groups in demographics, mean DHI or HADS-anxiety scores, or DSM-IV diagnoses. The CSD group had higher mean HADS-depression and NEO-PI-R trait anxiety, but lower NEO-PI-R extraversion, warmth, positive emotions, openness to feelings, and trust (all p<0.05). CSD subjects were significantly more likely than comparison subjects to have a composite temperament of high trait anxiety plus low warmth or excitement seeking.

CONCLUSION

An anxious, introverted temperament is strongly associated with CSD and may be a risk factor for developing this syndrome.

Adverse effects of health anxiety on management of a patient with benign paroxysmal positional vertigo, vestibular migraine and chronic subjective dizziness

INTRODUCTION

Care of patients with vestibular symptoms focuses primarily on physical otoneurologic disorders; however, psychological factors can sustain symptoms, confound assessment, and adversely affect treatment. Health anxiety is a particularly pernicious process that simultaneously magnifies physical symptoms and inhibits medical care.

OBJECTIVE

To demonstrate the excess morbidity caused by vestibular health anxiety and its successful management in a patient with otoneurologic disease.

METHOD

Report of a 41-year-old woman with recurrent benign paroxysmal positional vertigo, vestibular migraine, and chronic subjective dizziness, who expressed grave concerns about her health, repeatedly questioned her otoneurologic diagnoses, and failed physical therapy and medication treatment until her health anxiety and otoneurologic illnesses were addressed simultaneously.

CONCLUSION

Health anxiety is an empirically validated concept that explains troublesome health-related beliefs and behaviors. It is frustrating for patients and health care teams, but can be treated successfully in otoneurology practice, thereby reducing physical symptoms, emotional distress, functional impairment, and health care overutilization.

Central hyperadrenergic state after lightning strike

OBJECTIVE

To describe and review autonomic complications of lightning strike.

METHODS

Case report and laboratory data including autonomic function tests in a subject who was struck by lightning.

RESULTS

A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems.

INTERPRETATION

The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation was highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the central nervous system or a secondary response is open to speculation.

Inter-relationship of the functional status question of the PHQ-9 and depression remission after six months of collaborative care management

In collaborative care management (CCM) for depression, a restoration of premorbid functional status is as important as symptom reduction. The goal of this study was to investigate if the baseline functional status of the patient (as determined by the tenth question of the PHQ-9) was an independent predictor of clinical outcomes six months after enrollment into CCM and the interdependence of clinical outcomes on functional improvement at six months. One thousand eighty three adult patients who were enrolled in CCM for the diagnosis of major depression or dysthymia and had a PHQ-9 score of 10 or greater were retrospectively reviewed. Using a multiple regression model for clinical remission six months after enrollment into CCM; age, race and gender were not significant predictors of remission, however, being married was (OR 1.323 CI 1.013-1.727, P = 0.040). Patients in the Extremely Difficult category had an odds ratio of remission of 0.610 (CI 0.392-0.945, P = 0.028) at six months compared to the Somewhat Difficult group. Also, the odds of a patient achieving normal functional status at six months was highly correlated to clinical remission (PHQ-9 <5) with an odds ratio of 218.530 (P < 0.001). Depressed patients with worsening functional status at enrollment into CCM are less likely to achieve remission after six months, independent of all other variables studied. Also, improvement of a patient's functional status at six months was highly correlated with clinical remission.

Clinical clues to a dizzying headache

Recent years have witnessed an upsurge of interest in migraine as a cause of vestibular symptoms. Starting with 1970s case reports linking migraine to childhood vertigo, neurotologists worldwide have increasingly diagnosed migraine. Various syndromes of vestibular migraine (VM) have been described, diagnostic criteria proposed, epidemiologic data collected, and neurophysiologic models developed. Yet, the concept that migraine causes vestibular symptoms rests on a surprisingly thin research database. Current concepts of VM are based on expert opinion, not empirical data. No general consensus exists about the definition of VM. No studies have analyzed its essential features. Just one well-controlled medication trial has been published. No biomarkers are known. To stimulate more rigorous research, this paper poses three questions about clinical investigations into migraine and vestibular symptoms: What variables should be measured? What patients should be studied? How might clinical trials yield both clinically useful results and greater insights into pathophysiologic processes? Using these questions, the limits of current knowledge are explored. Applicable research methods from epidemiology to genetics are examined. Pilot data demonstrating pharmacologic and genetic dissection techniques are presented. Ambitious, but practical, near-term clinical research goals are enumerated, including rigorous validation of diagnostic criteria and development of empirically derived management guidelines.

Behavioral aspects of vestibular rehabilitation

Behavioral factors are an integral part of the overall morbidity of patients with vertigo, dizziness, and balance disorders. Anxiety, depression, and more importantly, loss of balance confidence and sense of debility and handicap beleaguer patients with acute and chronic vestibular symptoms. Vestibular rehabilitation originated as a physical therapy, but a careful look at its research development and clinical applications show it to be as much, or perhaps more, a behavioral intervention. More patients referred for vestibular rehabilitation require habituation to chronic vestibular symptoms and motion sensitivity than compensation for active peripheral or central vestibular deficits. Vestibular rehabilitation may exert a positive effect on behavioral morbidity, but the benefits are somewhat uneven and do not always correlate with physical improvements. Health anxiety (i.e., excessive worry about the cause and consequences of physical symptoms) is an emerging concept in clinical psychiatry and psychology. It may offer an important key to understanding the debility and handicap experienced by many patients with vestibular symptoms and enhance the ability of vestibular rehabilitation to ameliorate their suffering.

Questioning the role of abuse in behavioral spells and epilepsy

Past sexual trauma is frequently linked to the development of behavioral spells, present among 30% of patients admitted for video/EEG monitoring. Current attempts to verify and explore mechanisms in this reported association revealed that patients with epilepsy (n=58) and those with behavioral spells (n=38) did not differ in their self-report of past sexual trauma (among approximately 38% in each group). Ninety percent (90%) of men with behavioral spells endorsed past physical abuse, however, compared with 45% of men with epilepsy, and 40% of men with spells likely met current criteria for posttraumatic stress disorder. Among all patients, the presence of past physical, but not sexual, abuse positively predicted the diagnosis of spells rather than epilepsy. Current findings do not support a preponderance of sexual trauma in behavioral spells, yet within the subset of men with spells, greater exposure to physical abuse and current symptoms of posttraumatic stress disorder may be important etiological and sustaining factors.

Chronic Subjective Dizziness Versus Conversion Disorder: Discussion of Clinical Findings and Rehabilitation

Purpose

Audiologists frequently encounter patients who complain of chronic dizziness or imbalance, in the absence of active vestibular or neurological deficits. Knowledge about conditions that cause this clinical presentation will allow audiologists to make important contributions to accurate diagnosis and effective management of these patients. This article reviews 2 such conditions, chronic subjective dizziness (CSD) and conversion disorder.

Method

A case of CSD and another of conversion disorder are presented, with a literature review of their clinical presentations, key diagnostic features, and treatment strategies. The role of the audiologist in assessing patients with these conditions and facilitating appropriate treatment referrals is discussed.

Conclusions

The audiologist is in a key position to identify individuals with CSD and conversion disorder, 2 conditions that can be effectively managed if properly recognized. The authors demonstrate an effective team approach program that includes the audiologist’s contribution to differential diagnosis, education of patients and other clinicians about these conditions, and development of recommendations for neurological, psychiatric, otologic, and physical therapy referrals.

Previously undetected metabolic syndromes and infectious diseases among psychiatric inpatients

OBJECTIVE

This study identified previously undetected metabolic and infectious disease among persons with serious mental illness who were admitted to psychiatric inpatient units.

METHODS

Observational-naturalistic methods were used to simulate universal screening in order to document evidence of undetected disease among 588 adult psychiatric patients. Data were obtained from medical records and laboratory tests.

RESULTS

Laboratory results showed that 10% of patients had HIV, 32% had hepatitis B, and 21% had hepatitis C. Glucose levels were elevated in 7%, and total cholesterol levels were elevated in 22%. Nearly 60% had body mass indices above 25. The treatment team missed a considerable proportion of infectious disease (95% of hepatitis B cases, 50% of hepatitis C cases, and 21% of HIV cases) and metabolic disorders (89% of cases with elevated total cholesterol levels and 97% of cases with elevated triglyceride levels). By contrast, only 18% of cases with elevated glucose levels were missed.

CONCLUSIONS

This study demonstrated very high prevalence of both metabolic disorders and infectious diseases in a psychiatric inpatient population.

Chronic subjective dizziness

This article reviews the authors' work, which expands on previous studies to confirm that anxiety-related processes cause or maintain symptoms of dizziness. Discussed are interventions directed at patients' underlying psychologic disorders, including current methods of pharmacotherapy and psychotherapy. Patients with chronic complaints of nonspecific dizziness can present frustrating diagnostic and therapeutic challenges, but can be offered definitive and palliative care. The authors emphasize the importance of eliciting a precise description of the dizziness sensation from the patient as the critical factor in delineating the specific diagnosis and guiding treatment.

Autonomic Nervous System Function in Chronic Dizziness

OBJECTIVE

The goals of this study were to validate the clinical diagnosis of autonomic dizziness as a cause of chronic nonvertiginous dizziness that may be exacerbated by physical exertion or orthostatic challenges, estimate its prevalence in a tertiary referral population, and investigate the usefulness of three autonomic challenges as objective tests for this condition.

STUDY DESIGN

Laboratory investigation of autonomic activity.

SETTING

Tertiary care balance center.

PATIENTS

Fifteen men and women with symptoms indicative of autonomic dizziness. Subjects with other causes of dizziness, histories of syncope, or psychiatric disorders were excluded.

INTERVENTIONS

Autonomic tests included 45 minutes of head upright tilt (HUT), 20 minutes of 5% CO2 inhalation and then HUT, and 2 minutes of voluntary hyperventilation and then HUT.

MAIN OUTCOME MEASURES

Patterns of cardiovascular and respiratory responses and subjective ratings of dizziness, autonomic symptoms, and anxiety during autonomic challenges.

RESULTS

Twelve subjects had evidence of autonomic dysfunction, including 10 with abnormal heart rate, blood pressure, or respiratory responses to HUT. Two other subjects had prolonged hypocarbia after voluntary hyperventilation. Many of these abnormalities would have been missed by current autonomic testing paradigms. In one subject, CO2 inhalation revealed latent anxiety. In two subjects, the presence of high symptom ratings without objective autonomic dysfunction prompted a successful search for other diagnoses.

CONCLUSION

Study results validated the clinical syndrome of autonomic dizziness. Autonomic testing protocols may have to be updated to detect clinically relevant abnormalities in patients with dizziness.

Paroxetine for prevention of depressive symptoms induced by interferon-alpha and ribavirin for hepatitis C

BACKGROUND

Whether antidepressants prevent depression during interferon-alpha/ribavirin treatment for hepatitis C virus infection has yet to be established.

AIM

To investigate the use of paroxetine in a prospective, double-blind, placebo-controlled study for this indication.

METHODS

Sixty-one hepatitis C virus-infected patients were randomly assigned to the antidepressant, paroxetine (n = 28), or placebo (n = 33), begun 2 weeks before and continued for 24 weeks during interferon-alpha/ribavirin treatment. Primary endpoints included development of major depression and severity of depressive symptoms measured by the Montgomery Asberg Depression Rating Scale (MADRS).

RESULTS

Rates of major depression during the study were low (17%) and did not differ between groups. Nevertheless, using published MADRS cut-off scores, the percent of subjects who met criteria for mild, moderate or severe depression during interferon-alpha/ribavirin therapy was significantly lower in paroxetine- vs. placebo-treated subjects (P = 0.02, Fisher's exact test). Assignment to paroxetine was also associated with significantly reduced depressive symptom severity. This effect was largely accounted for by participants with depression scores above the median (MADRS > 3) at baseline in whom paroxetine was associated with a maximal reduction in MADRS scores of 10.3 (95% CI: 2.1-18.5) compared with placebo at 20 weeks (P < 0.01). Study limitations included a small sample size and high drop-out rate.

CONCLUSION

This double-blind, placebo-controlled trial provides preliminary data in support of antidepressant pre-treatment in hepatitis C virus patients with elevated depressive symptoms at baseline.

Expanding the differential diagnosis of chronic dizziness

OBJECTIVE

To improve treatment outcomes for patients with chronic dizziness by identifying clinical conditions associated with persistent symptoms and delineating key diagnostic features that differentiate its causes and direct attention to specific treatments.

DESIGN

Prospective cohort study from 1998 to 2004.

SETTING

Tertiary care balance center.

PATIENTS

A total of 345 men and women, aged 15 to 89 years, referred for evaluation of chronic dizziness (duration of > or =3 months) of uncertain cause.

INTERVENTIONS

Patients were systematically directed through multiple specialty examinations until definitive diagnoses were made.

MAIN OUTCOME MEASURE

Final diagnoses associated with dizziness.

RESULTS

Nearly all patients with chronic subjective dizziness were diagnosed with psychiatric or neurologic illnesses. These included primary and secondary anxiety disorders (n = 206 [59.7%]) and central nervous system conditions (n = 133 [38.6%]), specifically migraine headaches, mild traumatic brain injuries, and neurally mediated dysautonomias. A small number of patients (6 [1.7%]) had dysrhythmias. Four of 5 patients with migraine or dysrhythmias had comorbid anxiety.

CONCLUSIONS

Chronic dizziness has several common causes, including anxiety disorders, migraine, traumatic brain injuries, and dysautonomia, that require different treatments. Key features of the clinical history distinguish these illnesses from one another and from active neurotologic conditions. The high prevalence of secondary anxiety may give a false impression of psychogenicity.

Chronic dizziness: the interface between psychiatry and neuro-otology

PURPOSE OF REVIEW

This paper reviews the often-enigmatic relationships between dizziness and psychiatric symptoms. Psychiatric causes of dizziness, neuro-otologic causes of anxiety, underrecognized co-morbid conditions, and medical illnesses that masquerade as 'psychogenic' dizziness are examined. Key clinical features and data from recent treatment trials are presented with potential pathophysiologic mechanisms.

RECENT FINDINGS

Investigations at the interface between psychiatry and neuro-otology have identified the distinguishing features of several clinical conditions that present with non-vertiginous dizziness, subjective imbalance, and psychiatric symptoms. The most common condition is chronic subjective dizziness; a refinement of earlier concepts of psychogenic dizziness, phobic postural vertigo, and space-motion phobia. Chronic subjective dizziness is consistent with advancing research on anxiety and somatoform disorders and offers greater insights into the relationships between neuro-otologic illnesses and anxiety. Migraine, post-concussional syndrome, and dysautonomias also cause persistent dizziness and may be misdiagnosed or malingering or psychogenic dizziness because they often present with comorbid psychiatric symptoms in the absence of identifiable vestibular deficits.

SUMMARY

Recent research has defined the key features of several medical-psychiatric conditions that cause chronic dizziness, permitting greater diagnostic precision and insight into underlying pathophysiologic processes. Treatment studies have identified potentially effective interventions, which must be evaluated in controlled clinical trials.