Abstract
Purpose
The aim of this study was to evaluate the effects of a brief cognitive behavior therapy (CBT) intervention on the physical symptoms, illness-related disability, and psychologic distress of patients with chronic subjective dizziness.
Materials and methods
Forty-one patients with chronic subjective dizziness referred by a neurootologic clinic were randomly assigned to immediate treatment or a wait-list control. Three weekly treatment sessions based on the CBT model of panic disorder, adapted for patients with dizziness, were administered by a clinical psychologist. Treatment included psychoeducation, behavioral experiments, exposure to feared stimuli, and attentional refocusing. Outcomes were measured on the Dizziness Handicap Inventory and the Depression, Anxiety and Stress Scales. Two further measures developed for this study; the Dizziness Symptoms Inventory and the Safety Behaviours Inventory were used to measure physical symptoms and safety behaviors.
Results
The intervention was associated with significant reductions in disability on the Dizziness Handicap Inventory, reduced dizziness and related physical symptoms on the Dizziness Symptoms Inventory, and reduced avoidance and safety behaviors as measured by the Safety Behaviours Inventory. Pre- to posteffect sizes ranged from 0.98 to 1.15. There was no change in psychologic outcomes measured on the Depression, Anxiety and Stress Scales.
Conclusions
A 3-session psychologic intervention based on the CBT model can produce significant improvements in dizziness-related symptoms, disability, and functional impairment among patients with chronic subjective dizziness. This suggests that treatment of this condition may be reasonably simple and cost-effective for most of the patients.
1
Introduction
Dizziness is very common in primary care settings , neurology practice , and the general population . An association between dizziness and anxiety disorders has been found in many studies . It is widely acknowledged that a significant proportion of patients seen in neurootologic clinics have dizziness that is maintained by psychologic factors, most notably anxiety .
Ruckenstein and Staab observe that most patients with psychophysiologic dizziness have anxiety disorders that were produced by or coexist with a neurootologic illness. Frequently, anxiety is triggered by a vestibular event (such as rotational vertigo) related to a neurootologic disorder; however, once activated, it produces dizziness and other somatic symptoms that are maintained via psychophysiologic mechanisms .
Staab points to the similarities between panic disorder and psychophysiologic dizziness, in that both involve conditioned threat responses to aversive physiologic sensations. According to the cognitive model of panic disorder , individuals experience recurrent panic attacks because they misinterpret benign bodily sensations (fight or flight response) as indications of impending catastrophe. This leads to a positive feedback loop, in which misinterpretations of bodily sensations increase anxiety, which in turn strengthen the sensations, producing a self-perpetuating cycle. In our observation, very similar processes operate in patients with psychophysiologic dizziness, except that the unconditioned stimulus is a vestibular event rather than a panic attack. If the maintaining factors in the 2 disorders are indeed similar, then treatments that are effective for panic disorder may also benefit patients with psychophysiologic dizziness.
In the last 2 decades, studies by Brandt et al and more recently Staab and Ruckenstein have provided theoretical frameworks for understanding psychophysiologic dizziness and have helped to define the characteristics of common syndromes. Brandt et al described “phobic postural vertigo,” comprising dizziness and subjective imbalance, episodic “attacks” of fluctuating unsteadiness or illusory body perturbations, and exacerbated symptoms, often in response to perceptional stimuli (bridges, staircases, streets, shops, and social situations). They contend that vulnerable patients frequently have an obsessive-compulsive personality style with labile affect, and illness onset usually follows high levels of stress or a vestibular disorder. Staab and Ruckenstein subsequently described “chronic subjective dizziness” (CSD) as nonrotational dizziness, lightheadedness, feelings of “fullness” or “heaviness” in the head, subjective imbalance, and hypersensitivity to motion stimuli. Predisposing factors include anxious personality (neuroticism or phobic anxious temperament) and prior vestibular insult .
To date the most common treatments for CSD have been antidepressant medication—predominantly selective serotonin re-uptake inhibitors (SSRIs). These medications have been shown to reduce and, in some cases, resolve dizziness ; however, not all patients benefit. For instance, Staab et al found that 22 of 60 dizzy patients treated with SSRIs experienced no benefit or were unable to tolerate medication because of side effects.
Vestibular rehabilitation (VR) has also been found to improve outcomes in many patients with dizziness . The aim is to facilitate central nervous system (CNS) compensation for vestibular deficits through the use of specific exercises. However, in patients without vestibular deficits (whose symptoms are psychophysiologic), the mechanisms underlying symptom reduction after VR are not clear. Beidel and Horak point to similarities between VR and exposure therapy, the latter being a key component of cognitive behavior therapy (CBT) for anxiety. Both VR and CBT use exposure exercises, although VR is specifically designed to facilitate CNS compensation for vestibular deficits, whereas exposure therapy used in CBT aims to facilitate anxiety reduction via habituation. It is feasible that, in patients for whom dizziness is primarily driven by anxiety, the mechanisms of change in response to VR are primarily psychologic. If this is the case, exposure therapy, which is generally less complex and resource intensive, may be a more parsimonious option.
To date, few psychologic treatments for CSD have been reported, and existing studies have been small. Nevertheless, the few published trials yield promising results. Most included components of the cognitive behavior model for anxiety disorders ; however, the treatments varied in duration and content.
Brandt et al followed up 78 patients who had received a standard treatment (comprising 2-3 sessions) after their diagnosis of phobic postural vertigo at their treatment facility. The evaluation was conducted between 6 months and 5.5 years after their original referral and treatment (average follow-up period was 2.5 years). The treatment had aimed to reduce fear of the symptoms and comprised an explanation of the underlying mechanisms and an assurance that their condition is known and manageable. Patients were advised against dwelling on their illness and encouraged to use repeated exposure to situations that provoked dizziness. They were also encouraged to do regular physical activity. At follow-up, 22% of patients were symptom free, 50% were considerably improved, and 28% reported no improvement. The absence of a control group limited the conclusions that could be drawn.
Two small randomized studies conducted by Swedish researchers evaluated the effects of VR combined with CBT. The first evaluated a group program delivered over 5 sessions to older people (>65 years). Participants were randomly assigned to treatment (n = 9) or wait-list control group (n = 10). Vestibular rehabilitation was a major component of treatment and included a graded walking and balance program. Participants learned about the anatomy and function of the balance system, dizziness, and vestibular compensation. The CBT component comprised applied relaxation, graded exposure to situations that were being avoided, and psychoeducation about the relationships between thoughts and feelings. Significant improvements were found on some tests of physical abilities and in levels of disability on the Dizziness Handicap Inventory (DHI). There was no change in symptoms of vertigo, anxiety, or depression. As the treatment was primarily VR, with a small component of CBT, it is unclear whether the latter produced any independent benefit. Small sample size and absence of follow-up outcomes were limitations of the study.
In the second study, Andersson et al applied a similar treatment with younger individuals (aged between 22 and 62 years) and with a greater emphasis on cognitive conceptualization. Twenty-nine participants were randomized to treatment (n = 14) or wait-list control group (n = 15). Treatment was administered in groups of 3 to 4 individuals over 5 sessions, plus 1 telephone call. Vestibular rehabilitation exercises to stimulate vestibular compensation and improve balance were supplemented by applied relaxation and exposure exercises. Posttreatment outcomes once again revealed improvements on tests of physical capabilities and illness-related disability. Distress associated with dizziness also reduced following treatment, although there were no changes on measures of anxiety, depression, perceived stress, and confidence in everyday activities. Because the treatment comprised both VR and CBT, the relative contribution of each is unknown. The study was also limited by the absence of follow-up data.
Holmberg et al compared outcomes of 39 dizzy patients undergoing a self-administered VR treatment program with or without an additional CBT intervention. The VR treatment comprised information about the condition and a program that involved deliberately provoking dizziness twice a day. The additional CBT intervention comprised 8 to 12 individually tailored sessions that included written recordings of self-observations, exposure exercises, and an explanation of spontaneous body sway as being benign and normal. Controlled breathing and applied relaxation techniques were taught and promoted for use during exposure exercises. Outcome data revealed greater reductions in anxiety, depression, and self-reported handicap among patients who received the CBT intervention. These improvements were not sustained at the 1 year follow-up assessment .
Over the past 6 years, 1 of the researchers (SE) has been treating patients with CSD referred via a neurologist (PC) at a neurootologic clinic. A brief treatment protocol based on the CBT model of panic disorder was developed and has been used over this time. Consistent with the model, it was hypothesized that patients with CSD make catastrophic interpretations of their bodily sensations, which maintains anxiety and thus strengthens somatic symptoms via a self-perpetuating cycle. The aim of the current study was to evaluate the treatment via a randomized controlled trial.
We hypothesized that relative to wait-list control, treatment would lead to significant reductions in physical symptoms and associated disability, functional impairment, anxiety, and depression.
2
Method
2.1
Participants
Participants were 41 consecutive patients referred by a neurootologic clinic for psychologic assessment and treatment of CSD. Participants (73% female) had a mean age of 46.78 years (SD, 12.65). Eighty-three percent were married or in de facto relationships, 12.2% were never married, and 4.9% were separated or divorced. Nationalities included Australian (80.5%), British (7.3%), Assyrian (2.4%), Greek (2.4%), Irish (2.4%), Polish (2.4%), and Serbian (2.4%). Employment status included 39% in full-time work, 19.5% in part-time work, 9.8% carers/home duties, 7.3% in casual work, 7.3% unemployed, 7.3% retired, 4.9% disabled, and 4.9% student.
Inclusion criteria required a diagnosis of CSD (based on a cluster of unexplained symptoms including dizziness/lightheadedness, feelings of “fullness” in the head, subjective imbalance, and exacerbation of symptoms in busy public places) and age between 18 and 70 years. Psychosis, significant drug or alcohol dependence, suicidal ideation, or significant cognitive deficit were the exclusion criteria. The duration of dizziness and related symptoms in this sample ranged from 1 to 240 months (median, 9 months; mean, 34.90; SD, 56.41), with 4 participants reporting a previous period of dizziness that had subsequently resolved (duration range, 2-48 months). Medical diagnoses included benign paroxysmal positional vertigo (24.4%), vertigo episode(s) with no clear vestibular pathology diagnosed (26.8%), migrainous vertigo (12.2%), Ménière disease (4.9%), labyrinthitis (4.9%), and no vertigo episodes or vestibular pathology (22.0%).
The anxiety and depression modules of the Mini International Neuropsychiatric Interview (MINI) were administered over the telephone to study participants shortly after recruitment. Based on this assessment, 16 participants (39%) met criteria for generalized anxiety disorder, 16 (39%) for major depressive disorder, 15 (36.6%) for panic disorder, 2 (4.9%) for dysthymia, and 1 (2.4%) for social phobia. Nine participants (22%) did not meet criteria for any comorbid anxiety or depressive disorders. Among patients who met criteria for a disorder, the number of diagnoses per patient ranged from 0 to 4 (mean, 1.66; SD, 0.87).
2.2
Measures
2.2.1
Mini International Neuropsychiatric Interview
The MINI is a structured diagnostic interview for psychiatric diagnoses in the Diagnostic and Statistical Manual . In this study, the current anxiety and depressive disorder modules of the MINI were administered, as well as the suicidality, alcohol dependence, and substance dependence modules. The aim was to identify comorbid psychiatric diagnoses. Interrater reliability ( κ = 0.88-1.00) and test-retest reliability ( κ = 0.65-0.96 over 1-2 days) are acceptable for the diagnostic modules used in the current study, and evidence of construct validity has been demonstrated .
2.2.2
Dizziness Handicap Inventory
The DHI consists of 25 items that assess self-perceived disability associated with dizziness in 3 domains (functional, emotional, and physical). The composite score (rather than subscale scores) was used in the current study for consistency with previous research . Internal consistency ( α = .89) and test-retest reliability ( r = 0.97, within 1 day) are good . Evidence of convergent validity and sensitivity to change after treatment has been provided .
2.2.3
Dizziness Symptom Inventory
The Dizziness Symptom Inventory (DSI) is a measure of symptom severity developed and used by the key researcher (SE) with this cohort since 2006. Items are based on symptoms described by Staab plus some further symptoms that we frequently observe in these patients. The 22-item scale rates symptom severity over the preceding week and uses a 4-point scale. In the present study, internal consistency was good ( α = .82).
2.2.4
Safety Behaviours Inventory
The Safety Behaviours Inventory (SBI) is an 18-item descriptive measure that was developed for the present study to index the frequency of safety behaviors used in response to their condition. Items included walking close to walls; relying on another person to accompany them; and avoiding driving, shopping, exercise, and social activity. These behaviors impact on quality of life and are common to many anxiety disorders . Internal consistency ( α = .90) in the current study was good.
2.2.5
Depression, Anxiety and Stress Scales 21
The Depression, Anxiety and Stress Scales 21 (DASS-21) is a 21-item scale consisting of 3 subscales that measure symptoms of depression, anxious arousal, and psychologic stress. Internal consistencies (depression scale r = 0.94, anxiety scale r = 0.87, stress scale r = 0.91) are good, and evidence of factor structure, convergent validity, and discriminant validity has been demonstrated . Test-retest reliability for the DASS (42-item version) is acceptable ( r = 0.71-0.81), although temporal stability for the DASS-21 is yet to be established . In the current study, internal consistencies were depression scale α = .87, anxiety scale α = .72, and stress scale α = .88.
2.3
Procedure
The study was approved by St Vincent’s Hospital Human Ethics Committee and thus conforms to the ethical standards laid down in the 1964 Declaration of Helsinki. Participants were recruited from a specialist neurootologic clinic. They were given a flyer about the study by the treating neurologist (PC) and invited to contact the researchers. Patients who called were given a more detailed explanation of the study and were sent an information sheet describing the procedures in detail. Those who agreed to participate gave their informed consent and were randomized to treatment or a wait-list condition. Randomization was based on a random number sequence generated at www.random.org . The MINI was then administered over the telephone. Participants in the treatment group (n = 20) commenced treatment immediately, whereas wait-list participants (n = 21) commenced treatment 4 weeks later. Participants completed self-report measures at recruitment and at pre- and posttreatment. Data for the 6-month follow-up period are currently being collected.
2.4
Treatment
Treatment was delivered individually by a clinical psychologist (SE) over 3 weekly sessions. It included the following components:
- 1.
Psychoeducation about CSD—the syndrome, its causes, and maintaining factors. This was reinforced by an information flyer. (We used the label “psycho-physiological dizziness” to emphasize that the symptoms are real but are maintained by psychologic factors). The aim was to provide a low-threat explanation for the occurrence and persistence of physical symptoms. A case formulation was provided for each participant to help them make sense of their experiences from a psychophysiologic perspective.
- 2.
In-session behavioral experiments were used to demonstrate the effects of hypervigilance and attention switching on dizziness and associated symptoms. For instance, exercises such as standing on one foot, distraction activities, and memory tasks were used to demonstrate the effects of attention switching on the presence and intensity of symptoms. These exercises aimed to provide evidence for the psychophysiologic explanation of their symptoms and so reduce threat perceptions relating to the possibility of an undiagnosed serious medical illness.
- 3.
Avoidance and safety behaviors were identified, and information on the negative consequences of these behaviors was provided. Exposure exercises targeting feared situations were prescribed, and patients were given a form on which to record the date, duration, and intensity of symptoms associated with each exposure. Increased activity and exercise were strongly encouraged.
- 4.
Alternative strategies for responding to dizziness and associated symptoms were demonstrated. Participants were encouraged to observe the symptoms with calm detachment and then switch their attention to the task at hand or to another focal point using attentional refocusing cues (eg, memory tasks) if necessary. We used the metaphor of “surfing” the symptoms (a term coined by Baillie and Rapee in treatment for panic disorder) to suggest “surfing with the wave” as opposed to “swimming against the tide.” The aim was not to resist the sensations or give them any special attention but to “let them be.” In some cases, interoceptive exposure exercises were used (for example deliberately moving one’s head to provoke the symptoms), and patients were then encouraged to practice “surfing” them.
- 5.
The importance of getting on with life now, rather than waiting until their symptoms disappear, was stressed. Patients were encouraged to resume their normal lifestyle and focus on their external world regardless of their symptoms rather than monitoring or trying to control them.
We chose to limit treatment to 3 sessions because prior clinical experience suggested that most patients improved significantly after 2 to 3 sessions.
2
Method
2.1
Participants
Participants were 41 consecutive patients referred by a neurootologic clinic for psychologic assessment and treatment of CSD. Participants (73% female) had a mean age of 46.78 years (SD, 12.65). Eighty-three percent were married or in de facto relationships, 12.2% were never married, and 4.9% were separated or divorced. Nationalities included Australian (80.5%), British (7.3%), Assyrian (2.4%), Greek (2.4%), Irish (2.4%), Polish (2.4%), and Serbian (2.4%). Employment status included 39% in full-time work, 19.5% in part-time work, 9.8% carers/home duties, 7.3% in casual work, 7.3% unemployed, 7.3% retired, 4.9% disabled, and 4.9% student.
Inclusion criteria required a diagnosis of CSD (based on a cluster of unexplained symptoms including dizziness/lightheadedness, feelings of “fullness” in the head, subjective imbalance, and exacerbation of symptoms in busy public places) and age between 18 and 70 years. Psychosis, significant drug or alcohol dependence, suicidal ideation, or significant cognitive deficit were the exclusion criteria. The duration of dizziness and related symptoms in this sample ranged from 1 to 240 months (median, 9 months; mean, 34.90; SD, 56.41), with 4 participants reporting a previous period of dizziness that had subsequently resolved (duration range, 2-48 months). Medical diagnoses included benign paroxysmal positional vertigo (24.4%), vertigo episode(s) with no clear vestibular pathology diagnosed (26.8%), migrainous vertigo (12.2%), Ménière disease (4.9%), labyrinthitis (4.9%), and no vertigo episodes or vestibular pathology (22.0%).
The anxiety and depression modules of the Mini International Neuropsychiatric Interview (MINI) were administered over the telephone to study participants shortly after recruitment. Based on this assessment, 16 participants (39%) met criteria for generalized anxiety disorder, 16 (39%) for major depressive disorder, 15 (36.6%) for panic disorder, 2 (4.9%) for dysthymia, and 1 (2.4%) for social phobia. Nine participants (22%) did not meet criteria for any comorbid anxiety or depressive disorders. Among patients who met criteria for a disorder, the number of diagnoses per patient ranged from 0 to 4 (mean, 1.66; SD, 0.87).
2.2
Measures
2.2.1
Mini International Neuropsychiatric Interview
The MINI is a structured diagnostic interview for psychiatric diagnoses in the Diagnostic and Statistical Manual . In this study, the current anxiety and depressive disorder modules of the MINI were administered, as well as the suicidality, alcohol dependence, and substance dependence modules. The aim was to identify comorbid psychiatric diagnoses. Interrater reliability ( κ = 0.88-1.00) and test-retest reliability ( κ = 0.65-0.96 over 1-2 days) are acceptable for the diagnostic modules used in the current study, and evidence of construct validity has been demonstrated .
2.2.2
Dizziness Handicap Inventory
The DHI consists of 25 items that assess self-perceived disability associated with dizziness in 3 domains (functional, emotional, and physical). The composite score (rather than subscale scores) was used in the current study for consistency with previous research . Internal consistency ( α = .89) and test-retest reliability ( r = 0.97, within 1 day) are good . Evidence of convergent validity and sensitivity to change after treatment has been provided .
2.2.3
Dizziness Symptom Inventory
The Dizziness Symptom Inventory (DSI) is a measure of symptom severity developed and used by the key researcher (SE) with this cohort since 2006. Items are based on symptoms described by Staab plus some further symptoms that we frequently observe in these patients. The 22-item scale rates symptom severity over the preceding week and uses a 4-point scale. In the present study, internal consistency was good ( α = .82).
2.2.4
Safety Behaviours Inventory
The Safety Behaviours Inventory (SBI) is an 18-item descriptive measure that was developed for the present study to index the frequency of safety behaviors used in response to their condition. Items included walking close to walls; relying on another person to accompany them; and avoiding driving, shopping, exercise, and social activity. These behaviors impact on quality of life and are common to many anxiety disorders . Internal consistency ( α = .90) in the current study was good.
2.2.5
Depression, Anxiety and Stress Scales 21
The Depression, Anxiety and Stress Scales 21 (DASS-21) is a 21-item scale consisting of 3 subscales that measure symptoms of depression, anxious arousal, and psychologic stress. Internal consistencies (depression scale r = 0.94, anxiety scale r = 0.87, stress scale r = 0.91) are good, and evidence of factor structure, convergent validity, and discriminant validity has been demonstrated . Test-retest reliability for the DASS (42-item version) is acceptable ( r = 0.71-0.81), although temporal stability for the DASS-21 is yet to be established . In the current study, internal consistencies were depression scale α = .87, anxiety scale α = .72, and stress scale α = .88.
2.3
Procedure
The study was approved by St Vincent’s Hospital Human Ethics Committee and thus conforms to the ethical standards laid down in the 1964 Declaration of Helsinki. Participants were recruited from a specialist neurootologic clinic. They were given a flyer about the study by the treating neurologist (PC) and invited to contact the researchers. Patients who called were given a more detailed explanation of the study and were sent an information sheet describing the procedures in detail. Those who agreed to participate gave their informed consent and were randomized to treatment or a wait-list condition. Randomization was based on a random number sequence generated at www.random.org . The MINI was then administered over the telephone. Participants in the treatment group (n = 20) commenced treatment immediately, whereas wait-list participants (n = 21) commenced treatment 4 weeks later. Participants completed self-report measures at recruitment and at pre- and posttreatment. Data for the 6-month follow-up period are currently being collected.
2.4
Treatment
Treatment was delivered individually by a clinical psychologist (SE) over 3 weekly sessions. It included the following components:
- 1.
Psychoeducation about CSD—the syndrome, its causes, and maintaining factors. This was reinforced by an information flyer. (We used the label “psycho-physiological dizziness” to emphasize that the symptoms are real but are maintained by psychologic factors). The aim was to provide a low-threat explanation for the occurrence and persistence of physical symptoms. A case formulation was provided for each participant to help them make sense of their experiences from a psychophysiologic perspective.
- 2.
In-session behavioral experiments were used to demonstrate the effects of hypervigilance and attention switching on dizziness and associated symptoms. For instance, exercises such as standing on one foot, distraction activities, and memory tasks were used to demonstrate the effects of attention switching on the presence and intensity of symptoms. These exercises aimed to provide evidence for the psychophysiologic explanation of their symptoms and so reduce threat perceptions relating to the possibility of an undiagnosed serious medical illness.
- 3.
Avoidance and safety behaviors were identified, and information on the negative consequences of these behaviors was provided. Exposure exercises targeting feared situations were prescribed, and patients were given a form on which to record the date, duration, and intensity of symptoms associated with each exposure. Increased activity and exercise were strongly encouraged.
- 4.
Alternative strategies for responding to dizziness and associated symptoms were demonstrated. Participants were encouraged to observe the symptoms with calm detachment and then switch their attention to the task at hand or to another focal point using attentional refocusing cues (eg, memory tasks) if necessary. We used the metaphor of “surfing” the symptoms (a term coined by Baillie and Rapee in treatment for panic disorder) to suggest “surfing with the wave” as opposed to “swimming against the tide.” The aim was not to resist the sensations or give them any special attention but to “let them be.” In some cases, interoceptive exposure exercises were used (for example deliberately moving one’s head to provoke the symptoms), and patients were then encouraged to practice “surfing” them.
- 5.
The importance of getting on with life now, rather than waiting until their symptoms disappear, was stressed. Patients were encouraged to resume their normal lifestyle and focus on their external world regardless of their symptoms rather than monitoring or trying to control them.
We chose to limit treatment to 3 sessions because prior clinical experience suggested that most patients improved significantly after 2 to 3 sessions.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
