Does systematic noise stimulation improve tinnitus habituation?

Schneider, E. , Hocker, K.M. , Lebisch, H., Pilgramm, M.

(aus: Hazell, J. (ed.): Proceedings of the Sixth International Tinnitus Seminar, Cambridge 1999)

Abstract: In addition to well established methods of counselling the noise generator seems to be a remarkable tool , which helps patients to reorient their attention to external acoustic stimuli. The study presented is planned to answer the question: Does systematic noise stimulation improve tinnitus habituation? The study compares the treatment outcomes of patients using a noise generator for half a year with the outcomes of patients who do not. Both groups received tinnitus counselling.

The patients included are from a rehabilitation hospital and from ear, nose and throat practitioners. The design and method of the study is presented and preliminary results are reported.

 

Introduction

Method

Results

Discussion

Introduction: The study presented is planned to answer the question:

Does systematic noise stimulation improve tinnitus habituation?

The study is in process. We will report the design of the study, the current state of our work and preliminary data from participating patients and their outcome so far.

In combination with well established methods of counselling [1,2,3] the noise generator seems to be a remarkable tool to help patients reorient their attention to external acoustic stimuli. [4,5,6].

The treatment principle of inhibiting tinnitus detection by systematic acoustic stimulation with a low level broad band noise - as proposed by Dr. Jastreboff and Dr. Hazell - promises a reduced duration to tinnitus perceptibility and to tinnitus annoyance. Can this decrease improve chances for stable and lasting symptom management?

One starting point of our study is that in Germany despite of the lack of controlled outcome studies there were high expectations concerning the use of a noise generator. In the past the fate of new approaches in tinnitus management could be described as: Waves of enthusiastic reactions in the public followed by deep scepticism towards the new method. That is why we try to contribute to a undistorted estimation of the situation.

The study presented compares the treatment outcomes of patients using a noise generator for half a year with the outcomes of patients who do not. Both groups received tinnitus counselling. The study was planned to involve patients of a rehabilitation hospital and patients of doctors of ear , nose and throat medicine.

The study is supported by the Deutsche Tinnitus Liga and Siemens Audiological Technique which is providing prototypes of special noise generators, and by the Staatsbad Bad Meinberg. The final data analysis will be made by the Institut für empirische Gesundheitsökonomie, a research institute specialised in clinical studies. This institute also supported the design of this study.

Method

Our hypotheses are:

that after 6 months people using the noise generator report a significantly less tinnitus annoyance than members of a control group.

that people using the noise generator report significantly fewer hours per day of tinnitus perceptibility and a significantly lower level of tinnitus loudness than members of a control group.

The noise generator is a device that is worn behind the ear. It produces broad band noise. Additionally, patients with hearing loss receive a device that combines a modern digital hearing aid with a noise generator. Both features can be controlled independently. This device provides external stimulation of the ear and an additional tool for the self monitoring of tinnitus loudness.

 

We chose a pretest-posttest control group design. The study includes patients from two treatment settings, which represent different intensities of counselling and cognitive behavioural intervention:

a.) patients from local ear, nose and throat practitioners who received a general 2 hour introduction in the model of tinnitus formation and tinnitus habituation and further counselling while they were using the noise generator

b.) patients of an inpatient rehabilitation tinnitus management program who received intensive psychological and medical support including cognitive restructuring and - for those who were in need of it - conflict oriented group psychotherapy, hypnosis or pharmakotherapy.

 

We planned to randomly assign patients to experimental and control groups. A total number of 180 patients was to be included. The experimental group was to use a noise generator, if needed in combination with a digital hearing aid, for approximately 6 hours a day for six months. Binaural use of the noise generator took place in cases where binaural tinnitus or tinnitus perceived in the head was reported. If tinnitus was perceived in only one ear the noise generator was used in the monaural way.

 

The control group received a skin reflex biofeedback device as a placebo condition. The use of the biofeedback device as a placebo is based on the notion that biofeedback therapy does not reduce tinnitus annoyance any more than the usual psychological techniques such as progressive muscle relaxation or Autogenic Training.

Criteria for inclusion of patients in the study were:

participants had to be suffering from chronic tinnitus with a total score in the Tinnitus Questionnaire [7] of at least 40, which excluded persons with lower levels of tinnitus annoyance and tinnitus related distress

Not admitted to the study were persons who applied for early pension, who were striving for financial benefits due to their impairment and thus might be refractory to improvement. This criterion is especially important in rehabilitation hospitals. In the rehabilitation hospital taking part in this study - the Brunnen-Klinik in Bad Meinberg - about 25% of the patients had to be excluded due to this criterion.

 

The following groups of variables were planned to be recorded at beginning of treatment, after a tinnitus management course, after a 6 months phase and in a 1 year follow up:

audiometric data at the beginning, during and after treatment

Tinnitus-questionnaire [7]

Beck Depression Inventory [8]

Tinnitus Disability Index with kind permission by Prof Kroener-Herwig who developed this adaptation from the Pain Disability Index [3,9,10]

patients self monitoring by noise generator, which as mentioned above, has a tool for self performed matching of tinnitus loudness

questionnaire on Tinnitus anamnesis (e.g. hours of tinnitus perceived, days off from work etc.)

after the 6 months period a standard interview was held with questions concerning tinnitus loudness, tinnitus annoyance, convenience of the use of the devices, importance of tinnitus in everyday life, changes in relationships or work conditions induced by the patients and other topics.

After the 6 months treatment phase participants were informed how they could obtain further counselling plus a noise generator in order to complete their treatment.

Results:

In February 1998 the first patients were introduced in the study. In the progress of the study we had to accept the fact that we could not motivate the outpatient participants to agree with the control group condition, because these participants had already been informed by their physicians and the media about a noise generator. More than 100 participants have already passed throughout the half year treatment phase. Viewing these data in July 99 16 participants had passed through the follow up.

As for the inpatient group we first asked them to consent to a randomised allocation to one of the two treatment conditions and to participation in the 3 additional therapy sessions after their stay in the hospital.

The drop out rate was about 10% in each group.

We are looking forward to presenting the complete results once the data collection is completed. Cautious interpretation of our available data suggests that:

Most of the patients reported a significant reduction of symptoms during the half year treatment phase, which amounted to 1.7 units of standard deviation on the Tinnitus Questionnaire, about 0.7 units of standard deviations for the Beck Depression Inventory and about 0.5 units of standard deviations for the Tinnitus Disability Index. (Data here including participants from the rehabilitation hospital) The experimental group showed slightly superior outcomes in the psychometric measures. A final analysis of data will indicate whether psychometric measures show significant differences between control group and experimental group supporting our hypothesis.

Figure 1 (near here):Psychometric measures

 

After the 6 months treatment phase we asked : "How many hours a day do you perceive tinnitus" : about 25% of the members of control group, but more than 35 % of the members of experimental group reported that they perceived tinnitus less than 8 hours a day.

Self induced changes in everyday life, for example reducing work stress or solving conflicts in relationships, had an impact on the self reported annoyance by tinnitus after the six months treatment phase. Nearly 50% of the participants reported substantial changes in everyday life. 95% of the patients with such changes remarked a reduction of tinnitus annoyance, while only 75% participants without such changes indicated a reduction. In our opinion psychosocial stressors play a dominant role in tinnitus annoyance, can inhibit tinnitus habituation and are a moderator variable in our study.

Figure 2 (near here). Self induced changes in everyday life and tinnitus annoyance

31% of the experimental group and 4 % of the control group reported that tinnitus had lost it´s importance in their lives.

Figure 3 (near here):Importance of tinnitus after treatment

Discussion and conclusion

One point can be definitely stated: Patients reported that they experienced the noise generator as a convenient aid in learning to live with tinnitus and to manage tinnitus. Very often participants described the noise generator as an easy to use and efficient help in focusing attention on other stimuli than tinnitus.

In fact, systematic noise stimulation is a valuable tool in accomplishing tinnitus habituation.

 

 

l)References:

1. Goebel, G. (ed.): Ohrgeräusche - Psychosomatische Aspekte des komplexen chronischen Tinnitus; Quintessenz, München 1992

2. Hallam, R.: Leben mit Tinnitus , München 1994

3. Kröner-Herwig, Birgit (ed): Psychologische Behandlung des chronischen Tinnitus; Weinheim 1997

4. Jastreboff, Pawel J.: Processing of the Tinnitus Signal Within the Brain; in: Reich u. Vernon, 1996, S. 58-68

5. Sheldrake J.B., McKinney CJ, Hazell J.W.P.: Practical aspects of retraining therapy; in : Reich u. Vernon, 1996, S. 537-539

6. Reich, Gloria E., Vernon, J.A. (ed.): Proceedings of the Fifth International Tinnitus Seminar, July 12-15, 1995, Portland; American Tinnitus Association, Portland 1996

7. Goebel, G., Hiller, W.: Tinnitus-Fragebogen; Göttingen 1998

8. Hautzinger, M. et al.: Beck Depressions Inventar BDI; translated and adapted by Verlag Hans Huber, Bern , 1994

9. Pollard, C.A. (1984): Preliminary validity study of the Pain Disability Index. Perceptual and Motor Skills, 59, 974 f.

10. Nilges, P. et al.: Qualitätssicherung in der Therapie chronischer Schmerzen, Teil VI. Der Schmerz, 9, 242-247, 1995