Why Does Vertigo Become Chronic After Neuropathia Vestibularis? FRANK GODEMANN, MD, CHRISTIANE KOFFROTH, MD, PETER NEU, MD,

AND

ISABELLA HEUSER, MD

Objective: Vertigo is one of the most frequent complaints in general medical practice and is often linked to psychiatric disorders. A longitudinal study of 67 patients with an acute vestibular disorder was undertaken to clarify if, after experiencing acute vestibular vertigo, certain patients have a higher likelihood of developing chronic, debilitating dizziness despite no evidence of a damaged peripheral vestibular system. Method: The severity of dizziness was determined in 67 patients with vestibular neuronitis, 6 months after their release from hospital, using the Vertigo Symptom Scale from Yardley et al. The intensity of anxiety directly after vertigo was experienced, body-related cognitions, illness coping, personality structure, and the recovery of the organ of equilibrium were recorded in order to explain the severity of vertigo that occurred after 6 months. The function of the organ of equilibrium was assessed by using a caloric test. Results: Over a period of 6 months, 13 of the 67 patients (19.4%) reported continuing dizziness after neuropathia vestibularis. Eleven of the 13 patients showed high scores on a scale for measuring vertigo-related symptoms, which can be interpreted as being equivalent to anxiety. The variables of gender, catastrophic thoughts and a dependent personality accounted for 35% of why vertigo became chronic. Conclusion: Neuropathia vestibularis represents a risk factor for the development of chronic vertigo. Chronic vertigo after neuropathia vestibularis appears to be equivalent to anxiety and is partly conditional on catastrophic thoughts at the beginning. Key words: neuropathia vestibularis, chronic vertigo, psychogenic vertigo, risk factors. DIPS ⫽ Diagnostic Interview of Psychiatric Diagnoses; VSS ⫽ Vertigo Severity Scale; SA ⫽ somatic anxiety; VS ⫽ vertigo severity; STAI ⫽ State Trait Anxiety Inventory; ACQ ⫽ Agoraphobic Cognitions Questionnaire; BSQ ⫽ Body Sensations Questionnaire; PSSI ⫽ Personality Disorder and Type Inventory; FKV ⫽ Freiburg Coping Illness Questionnaire; MSP ⫽ mean slow phases; OE ⫽ organs of equilibrium.

INTRODUCTION ertigo is a common symptom in general medical practice (1). Neurological, ENT-related, cardiologic, and psychiatric disorders are the most frequent differential diagnoses (1,2). Results so far indicate that vertigo, independent of its etiology, has a tendency to become chronic. In more than 80% of all patients seeking consultation for vertigo, the vertigo symptoms did indeed improve within half a year, but only a third reached a full recovery (3). This leads to the question of whether these findings would also be prevalent among a homogeneous group of patients experiencing vertigo for the first time, and, if so, how many patients would subsequently develop chronic vertigo? In order to better understand why vertigo becomes chronic, we prospectively studied a group of patients with neuropathia vestibularis. Although neuropathia vestibularis is considered to be a benign illness where usually most or all symptoms disappear within 2 to 3 weeks, almost 50% of patients report the continuation of vertigo symptoms (4 –7). However, the quality of vertigo with neuropathia vestibularis changes over the course of an indefinite period of time: at the beginning, rotary vertigo with nausea and vomiting is experienced, later a feeling of insecurity and numbness (7). Two alternative models to explain why vertigo becomes

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From the Department of Psychiatry, Free University of Berlin, Berlin, Germany. Address correspondence and reprint requests to Frank Godemann, MD, Department of Psychiatry and Psychotherapy, Charite´ Hospital, Humboldt University at Berlin, Schumannstrasse 20/21, 10117 Berlin, Germany. E-mail: [email protected] Supported by grant no. DFG Go 923/1–1. Received for publication December 11, 2002; revision received May 17, 2004. DOI: 10.1097/01.psy.0000140004.06247.c9 Psychosomatic Medicine 66:783–787 (2004) 0033-3174/04/6605-0783 Copyright © 2004 by the American Psychosomatic Society

chronic are likely: 1) Persistent vertigo reflects an acquired mild vestibular dysfunction. It is hypothesized that these types of mild subthreshold vestibular dysfunctions become symptomatic if the individual experiences anxiety or hyperventilation, because the autonomous arousal overrides the central compensation mechanism (8). 2) At the onset, vertigo is accompanied by a strong feeling of anxiety (9). Later on, vertigo could also be understood as being equivalent to anxiety, without the person necessarily being consciously aware of their anxiety (10). In this experience, vertigo serves as a “model” for the subsequent development of anxiety as a symptom (11). Yardley et al. describes the various means of explanation as follows: “Transient, weak vestibular symptoms may hence be a common experience, but become a contributory factor for psychiatric disturbance only in those who are predisposed to react adversely to disorientation” (9). The relationship between the experience of anxiety and chronic vertigo is yet to be understood. Neuropathia vestibularis provides us with a suitable basis for shedding light on this relationship. We therefore included patients who had suffered an acute vestibular disorder in the study, monitoring the development of anxiety and vertigo over a period of 6 months. METHOD Eighty patients, who had been diagnosed as suffering from neuropathia vestibularis directly after their admission into hospital, were recruited over a period of 1.5 years from one neurological and seven ENT departments in Berlin.1 The criteria for inclusion in the study were an acute onset, rotary vertigo and nausea or vomiting. Additional requirements for inclusion were an abnormal caloric test result in the first 4 days after admission to hospital and/or spontaneous nystagmus. Only first-time sufferers were included. Patients with reduced hearing ability or tinnitus, the presence of a central vestibular condition, a head injury, or a previous anxiety disorder were excluded. A random sample (102 people) was recruited via the Berlin Residents’ Registration Office as a control group. The test participants received compensation of €50 for taking part in the study. With this random sample, 1 Departments of Otolaryngology of the Free University of Berlin, n ⫽ 26; St. Gertrauden Hospital, n ⫽ 16; St. Hedwig Hospital, n ⫽ 2; “Im Friedrichshain” Hospital, n ⫽ 11; “Prenzlauer Berg” Hospital, n ⫽ 8; “Neuko¨lln” Hospital, n ⫽ 8; Accident Hospital Berlin, n ⫽ 6; and the Department of Neurology of the Charite´, n ⫽ 3.

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F. GODEMANN et al. we were able to calculate Cronbach’s alpha and the correlation of Vertigo Symptom Scale (VSS) subscales, and to compare our caloric test results with a healthy control group. The VSS was selected as an independent variable for recording the severity of vertigo after 6 months. Patients indicate on a 5-point Likert scale (0 ⫽ “the symptom never occurred” to 4 ⫽ “the symptom occurred on average more than once a week”) the frequency of 22 vertigo symptoms over the past 6 months. The VSS consists of two subscales. Vertigo severity (VS) describes vertigo symptoms such as rotary vertigo, and somatic anxiety (SA) describes the autonomous accompanying symptoms of vertigo like sweating and sensations such as heart tremors or discomfort. With both subscales, Cronbach’s alpha is above 0.80 (VS ⫽ 0.88; SA ⫽ 0.83); the test-retest correlation is around 0.95. Both subscales correlate only moderately with each other (0.33– 0.46) and differentiate between vertigo patients and healthy controls. A stable correlation between the two subscales and the diagnosis of anxiety disorder is found in the literature (p ⬍ .05). In our patients with acute vestibular disorder, an improvement in the vertigo symptoms was to be expected within a few weeks. We therefore considered vertigo lasting over a number of months to have become chronic. We consider VS and SA scores as pathologic if they are higher than the mean value for outpatients of a special vertigo clinic (10). Panic disorder, agoraphobia, post-traumatic stress disorder, obsessivecompulsive disorder, and generalized anxiety disorder were diagnosed using the Diagnostic Interview for Psychiatric Disorders (12). Patients diagnosed as permanently suffering from these anxiety disorders were excluded from the evaluation, since chronic vertigo is often a symptom of these disorders (1,2,13–15). The influence of a wide range of variables on the development of chronic vertigo was investigated with the assistance of the following scales: STAI State and Trait, Freiburg Coping Illness Questionnaire, Agoraphobic Cognitions and Body Sensations Questionnaire, and Personality Type and Disorder Inventory. We selected these scales to test our main hypothesis that following acute vestibular disorder a number of patients are prone to develop psychogenic vertigo. These scales seemed to us to be particularly suited to identifying possible psychological risk factors. The State-Trait Anxiety Inventory (16) records both state anxiety and anxiety as a permanent personality trait. The questionnaire on body-related anxieties and cognitions (17) is a German translation of the Body Sensation Questionnaire (BSQ) and the Agoraphobic Cognitions Questionnaire (ACQ) (18). On a 5-point Likert scale in the BSQ, physical symptoms are assessed which, in confrontation with anxiety-producing stimuli, are experienced by patients as being particularly stressful. The ACQ records catastrophic thoughts in relation to body sensations, with the assistance of 14 items. The scale ranges from “the thought never occurs” (1) to “the thought always occurs” (5). The 14 items on the ACQ result in two total scores, describing anxiety before a control loss and the experience of a physical crisis in one’s own body. The Freiburg Coping Illness Questionnaire (FKV) from Muthny records five different coping styles (depressive coping, active problem-oriented coping, distraction and building self-esteem, religiousness and soul searching, as well as trivializing and wishful thinking) (19). The PSSI is a personality inventory developed by Kuhl and Kaze´ n depicting personality types and is oriented to ICD 10 within the framework of a dimensional understanding of personality (20). Three of 13 types are mentioned here (Table 1): careful-compulsive, schizo-typical, and loyal-dependent.2 Immediately after admission into hospital, patients assess their vertigo using a visual analogue scale (1 ⫽ no vertigo; 10 ⫽ heavy vertigo). The caloric test was carried out with the “Humid Air Caloric HAC 3” 6

2 Careful-compulsive: This style is characterized by thoroughness and exactness in the completion of the person’s own activities. The corresponding personality disorder is marked by perfectionism and rigidity. Schizo-typical: People with a particular sensibility for foreseeing events and actions which neither logical thought or intuitive experience could bring about. Loyal-dependent: There is a high readiness to defer one’s own desires, if they collide with the interests of an important reference person. In the extreme, this style can sometimes lead to dependent or submissive behavior.

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TABLE 1.

Characteristics of 67 Patients With Neuropathia Vestibularis Characteristic

Gender Male Female Age (years) Vertigo Severity Scale* Somatic anxiety (SA) SA ⱕ 1.32 SA ⱖ 1.33 Vertigo severity (VS) VS ⱕ 1.11 VS ⱖ 1.12 Vestibular side difference in caloric testing ⬍20% ⬎20%

Value

29 (43.3%) 38 (56.7%) 52 ⫾ 14.3

56 (83.6%) 11 (16.4%) 64 (95.5%) 3 (4.5%) Low SA ⬍ 1.33 5 (10%) 46 (90%) High SA ⱖ 1.33 4 (37%) 7 (63%)

*Vertigo Severity Scale subscales: VS ⫽ vertigo severity, SA ⫽ somatic anxiety; SA ⱖ 1.33 and VS ⱖ 1.12 ⫽ pathological scores. weeks after discharge from hospital. Initially, a warm water douche (44°C) was flushed into the healthy side for about 40 seconds. After a pause of 20 seconds, nystagmus was recorded for 90 seconds. The affected ear was then examined in the same way. Finally, cold flushing (30°C) of both the affected and healthy ear concluded the test. The function of the peripheral vestibular organs was calculated using Scherer’s formula. The mean slow phases (MSP) reflect the sensitivity of the organs of equilibrium (OE) in both the affected and healthy ear (21).

Statistical Methods Statistical evaluation of the data was carried out with SPSS for Windows, version 10.07. The Mann Whitney U-Test for independent random samples was used for rank comparison of scores with nonstandard distribution. Associations between two variables were determined using Pearson’s correlation coefficient. Partial correlation was calculated for the determination of apparent correlations. Testing of the independence of two variables was calculated with Pearson’s ␹2 test. Step-by-step linear regression analyses were used to determine the relevance of different variables. The data are presented in mean values and SD from the mean values. A p value of less than 0.05 was considered significant.

RESULTS Eighty patients were screened for the study. Six were excluded because anxiety disorder was diagnosed as having been present before the incidence of vertigo (panic disorder, n ⫽ 3; agoraphobia, n ⫽ 3). Data for 7 patients were incomplete, either because they had moved to an unknown address or because they had declined to take part in the caloric test. Of the 102 controls, 13 were excluded from the study due to an anxiety disorder (panic disorder, n ⫽ 2; agoraphobia, n ⫽ 3; agoraphobia with panic disorder, n ⫽ 3; generalized anxiety disorder, n ⫽ 5). The average age in the patient group was 52 (⫾14.3), and in the control group 51 (⫾11.5) years. There was therefore no significant age difference (t ⫽ ⫺0.31, p ⫽ .76) between the two groups. The patient group consisted of 38 women and 29 men, the control group of 35 women and 47 Psychosomatic Medicine 66:783–787 (2004)

CHRONIC VERTIGO AFTER NEUROPATHIA VESTIBULARIS men. There was no significant difference between the two groups with regard to gender distribution (␹2 ⫽ 2.91, p ⫽ .09). Of the 67 patients for whom data were evaluated, three had pathological scores on the vertigo severity scale (1.37–1.74; mean, 1.49 ⫾ 0.21) and 11 on the somatic anxiety scale (1.33–3.18; mean, 2.13 ⫾ 0.61). Only one female patient rated as pathological on both scales. The average score on the somatic anxiety scale was 0.73 (⫾0.76) and on the vertigo severity scale 0.28 (⫾0.37) (Table 2). Immediately after admission, patients tend to suffer from severe vertigo (visual analogue scale: 7.9 ⫾ 2.1). We found no correlation between the intensity of vertigo at the beginning and the values in the vertigo severity (p ⫽ ⫺0.24) or somatic anxiety scales (p ⫽ ⫺0,14) during the follow-up period. Correlations between the sensitivity of the organs of equilibrium 6 weeks after an acute one-sided vestibular dysfunction and vertigo severity after 6 months (0.13)/somatic anxiety (0.05) were not significant. Of the 11 patients with pathological scores on the somatic anxiety scale, seven (63%) indicated side differences of ⬎20%, and of the patients without persistent vertigo as many as 90% (46 of 51) had side differences of more than 20% (Table 2). Similar findings for side differences are found in the literature (21–23) and were also present in our healthy control group. The female gender seems to represent a risk factor in the development of chronic vertigo. All patients with high somatic anxiety scores were female (Pearson 11.8, p ⬍ .001, df ⫽ 1). The absolute scores for the severity of somatic anxiety were higher in the patient group than in our control group (0.73 vs. 0.53); however, this difference was not significant. The differences to the 11 patients with pathological vertigo scores were significantly higher than in the control group (2.13 vs. 0.53, U ⫽ 24, p ⬍ .001). All 11 vertigo scores were above the mean values for the Yardley and Hallam patient group who were attending a vertigo consultation (24). TABLE 2.

In comparison to patients whose symptoms had remitted, those with chronic vertigo after acute vestibular disorders were significantly more anxious after they had experienced the acute dysfunction of the organs of equilibrium. They had a stronger impression of losing control over their bodies (r ⫽ 0.41, p ⬍ .01) and experienced the dysfunction as a serious crisis (r ⫽ 0.35, p ⬍ .01). Physical symptoms such as dizziness significantly increased their anxiety (r ⫽ 0.44, p ⬍ .001) (Table 1). The evaluation of personality found “loyal-dependent” (p ⬍ .001), “compulsive” (p ⬍ .05) and “schizo-typical” (p ⬍ .05) personality types to be significantly more prevalent among patients with chronic vertigo. In all the other personality types, we found no significant difference. The average STAI trait for all patients was 36.01 (⫾10.51). This corresponds to the scores obtained in a German random sample (34.45 ⫾ 8.83). Anxiety as a personality trait was found to be significantly higher in patients whose vertigo had become chronic (r ⫽ 0.28, p ⬍ .05). The FKV indicated that only the coping strategy of “depressive coping” and vertigo after 6 months could be correlated (r ⫽ 0.30, p ⬍ .05). The other coping strategies were not in any way linked to the continuation of vertigo (Table 1). The Bonferroni correction procedure was subsequently carried out on 20 correlations in a post-study analysis. Following this correction procedure, with its significance level of p ⫽ .0025, the BSQ, ACQ total value, and dependent personality structure all remained significant. In a linear regression analysis, the predominant factors contributing to chronic vertigo were: the female gender, a dependent personality structure, and the tendency to evaluate body sensations fearfully (ACQ). Combined, these factors offer an explanation for 35% of the variance in vertigoassociated symptoms.

The Significance of Personality Traits, Coping Strategies, and Anxieties on Vertigo Becoming Chronic

Sensitivity of organs of equilibrium ACQ Total Physical crises Loss of control BSQ Total PSSI Careful-compulsive Schizo-typical Loyal-dependent STAI trait FKV Depressive coping

Somatic Anxiety ⱕ1.32

Somatic Anxiety ⱖ1.33

U

R

79.41 (81.32)

65.70 (41.00)

235.50

0.70 (n.s.)

1.31 (0.32) 1.35 (0.50) 1.34 (0.42)

1.90 (0.91) 1.89 (1.05) 1.97 (1.04)

164.00* 165.00* 199.00

0.46***† 0.35**† 0.41**†

1.92 (0.70)

2.69 (0.67)

128.5*

0.44**†

63.96 (26.17) 28.05 (24.79) 37.53 (27.48) 34.34 (8.73)

84.16 (18.41) 45.23 (30.72) 61.15 (30.11) 44.55 (14.64)

156.50* 182.50* 182.00* 183.50*

0.31* 0.28* 0.42***† 0.28*

1.80 (0.72)

2.24 (0.63)

179.00*

0.30*

ACQ ⫽ Agoraphobic Cognitions Questionnaire; BSQ ⫽ Body Sensation Questionnaire; PSSI ⫽ Personality Disorder and Type Inventory; STAI ⫽ State Trait Anxiety Inventory; FKV ⫽ Freiburg Coping Illness Questionnaire. Mann Whitney’s U-Test and Pearson’s correlation coefficient (r), *p ⬍ .05, **p ⬍ .01, ***p ⬍ .001; †Significant after Bonferroni correction procedure. Psychosomatic Medicine 66:783–787 (2004)

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F. GODEMANN et al. TABLE 3.

Prediction of Severity of Vertigo 6 Months After an Acute Vestibular Disorder in 67 Patients

ACQ total mean value Sex PSSI: loyal-dependent Excluded variables FKV: depressive coping PSSI: careful-compulsive STAI trait BSQ total mean value PSSI: nervous-schizo-typical

Corrected R²

F

0.196 0.302 0.344

16.87* 15.03* 12.37*

NS

NS

NS ⫽ not significant. *p ⬍ .001 (linear regression analysis).

DISCUSSION In our study, a proportion (20%) of patients suffered chronic symptoms following an acute vestibular disorder. The prognosis for patients experiencing vertigo for the first time is considerably better than that for patients already attending a vertigo clinic, who have a 66% chance of developing chronic vertigo (25). The results of our study suggest that chronic vertigo in our sample is a symptom of acquired anxiety because there is no correlation between vertigo complaints and the sensitivity of the organs of equilibrium. In addition, only a small number of patients (3 of 67) report typical vestibular symptoms like rotary vertigo and there is practically no overlap of reported vestibular symptoms with somatic anxiety in the VSS. We therefore show a shift from a vestibular to a somatoform vertigo. This contradicts the results obtained by Jacob et al. (23) and Yardley et al. (24), who state that in patients with vertigo within the scope of anxiety disorders (in particular agoraphobias) it is mostly a dysfunction of the peripheral organs of equilibrium that is diagnosed. In contrast, it could be that we found no correlation to caloric testing because, in nearly all patients, typical vestibular symptoms disappeared. Development of chronic vertigo depends in part on the female gender, dysfunctional coping with vertigo and a dependent personality type. Yardley et al. also found dysfunctional coping in a sevenmonth longitudinal study of 101 patients attending a vertigo consultation clinic. In their study, 45% of the patients described their handicap as the fear of losing control. It is likely that patients who develop chronic vertigo shift their focus of attention to the threat posed by their vertigo experience and thus induce, beyond the anxiety itself, further dizziness (25). In turn, this results in the avoidance of situations which could lead to the feared loss of control, resulting in the patients imposing further restrictions on their social activities and therefore feeling increasingly disabled by their vertigo (26). In our study, we have shown that this altered focus of attention is an important factor in the etiology of somatoform anxiety. It turned out that the STAI trait score for those patients who showed significant somatoform vertigo after 6 months was at 786

the beginning on average 10 points higher than the mean of the patients without vertigo (U ⫽ 183.50, p ⬍ .05). This supports the thesis that people with increased negative emotionality tend to observe their body a lot and to evaluate the symptoms observed negatively (27). Of the FKV only “depressive” coping showed a significant correlation with increased anxiety scores 6 months later (p ⬍ .05). A negative correlation, as would be expected for example with active problem-oriented coping, did not occur. Yardley also investigated vertigo patients in respect of the influence of illness coping on impediment caused by vertigo (“handicap”) and anxiety caused by vertigo (“distress”) after 7 months. She found that the conviction of having influence on the course of the illness correlated negatively with the impediment caused by vertigo 7 months later (p ⬍ .05) (28). Brandt and Dieterich describes a “phobic swaying vertigo” as being the second most common cause of chronic vertigo syndromes (29). The personality of these patients was found to be the obsessive-compulsive type. In our study, a rigid-compulsive personality type, but also a dependent personality structure, seemed to be more prevalent among chronic vertigo patients. Lilienfeld and Penna were able to show that anxiety sensitivity is linked to a dependent personality type (30). An association between anxiety disorders and dependent personality disorders has also been described (31,32). If we view vertigo as psychogenic in our study, our results are in line with these findings. As in our study, a dependent personality disorder has been found particularly in women (33). There are some limitations to our study. First, because we only have data starting from 6 weeks after the onset of vestibular dysfunction and, second, because caloric testing is a problematic method of examining neuropathia vestibularis, due to its low specificity. Thus, Yardley et al. were not able to establish a difference of any significance between 36 panic patients and 20 control participants in respect of audiology and caloric testing. Posturography, however, led to the destabilization of more than 60% of panic and agoraphobic patients, whereas this was only the case in 10% of the control group (22). The study gives no answer to the question of whether those suffering from any of the anxiety disorders are prone to somatic reactions like vertigo. We had to exclude these patients because our study design did not allow us to differentiate between the vertigo of an original anxiety disorder and the newly developed somatic symptoms. The study was able to show that about 20% of all patients suffer from persistent vertigo after an acute vestibular disorder. We suggest that this chronic vertigo is in reality a kind of fear. It would make sense to clarify whether in other functional studies of the balance function, such as posturography, indicators cannot also be found, that this experience of vertigo is not an expression of a persistent vestibular neuropathia or at least that functional deficits do not occur more frequently than in the group without vertigo. This is surely a limitation of the study. In addition, it would be interesting to discover whether this persistent experience of vertigo is a threshold symptom of, or an integral part of, a psychiatric disorder. Psychosomatic Medicine 66:783–787 (2004)

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