Which treatment works for whom? A comparison of sound-exposure therapies

Tinnitus, or the ringing of the ears, is defined as the perception of a
continuous sound, in the absence of a corresponding acoustic stimulus in the
external environment. It is estimated that in Europe over 70 million people
experience tinnitus and that for 7 million it creates a chronic incapacitating
condition, tenaciously haunting them up to the point where it interferes with
every aspect of their daily living. Residing within and confined to the
individual*s subjective and perceptual experience, tinnitus is not measurable
or quantifiable by objective physical recordings, and is furthermore not
traceable to disease, injury, or pathology in the brain or elsewhere.
Empirical evidence for either the effectiveness of curative tinnitus treatments
or for audiological interventions, such as hearing aids, and sound-generating
devices to mask the sound, is lacking. Moreover, the audiometric
characteristics of the tinnitus sound (loudness/pitch) hardly predict severity
of the condition, or treatment outcomes. Contrary to scientific evidence, the
clinical practice of masking/attenuating the tinnitus-sound is still the most
widespread tinnitus-treatment approach.
Presently I propose the counterintuitive conjecture that it is not the sound
itself which is so devastating, but it is rather threat-appraisals and
fear-conditioned responses as a result, which cause the chronic condition.
Indeed, empirical evidence is growing for the effectiveness of a cognitive
behavioral approach; i.e. fear-reducing exposure based therapies not only
decrease tinnitus severity and impact on daily life, but also contribute to
general well-being of patients. Our recent findings support the importance of
addressing tinnitus-related fear and fear-responses in the management of
patients with disabling tinnitus. In this project we will experimentally test
the idea that initial threat-appraisal and fearful responses, not only predict
increased tinnitus suffering, but also that a sound-based approach is
counterproductive in managing tinnitus complaints. Moreover, a recently
developed (and validated) Tinnitus-specific Behavioural Exposure Treatment
(T-BET), will be tested. This study may provide important input for existing
and novel tinnitus-treatment approaches.

Primary research questions:
1. Does tinnitusspecific- behavioural exposure-treatment (T-BET) decrease
tinnitus-related fear, tinnitus-severity and enhance recovery, when compared to
a masking-therapy with use of personalised on-ear masking-devices, or vice
versa?
2. Can we identify different sub-groups of patients who benefit more from one
approach over the other?
Secondary:
3. Can we identify clinically relevant behavioural/emotional markers by daily
assessments?
4. Can we identify risk/resilience factors in the patient group suffering from
mild- to severe tinnitus disability?

In a RCT, minimally 208 tinnitus-patients (N= 244, including 15% loss to
follow-up) recently diagnosed with tinnitus will be randomized (stratified on
severity TQ<= 46; and hearing level: PTA on 1, 2, and 4 Khz of 25 dB worst ear)
in a masking or exposure condition, with tinnitus-disability and severity as
independents and tinnitus-related fear, threat-appraisal, avoidance/safety
behaviour, and psychoacoustic measures (Andersson, 2003) as dependent
variables, at baseline, pre-/post-treatment, and follow-up at 3 and 6 months.
Tinnitus-related fear-responding and tinnitus-intensity (using self-report
diaries) during masking-exposure procedures during 12 weeks (6 weeks
masking-exposure procedures; 3 weeks pre-/post-measurements) will be assessed
daily.

Masking- and exposure-procedures will follow previously developed and validated
guidelines (Cima et al., 2012; Henry, Jastreboff, Jastreboff, Schechter, &
Fausti, 2003; Jastreboff, 2012).

The burdens and risks associated with participation in this study are
non-existent. The study-specific unique additional activity we standardly
request from all participating patients is for them to fill in a daily-diary
during a 3-week pre-intervention (pre-test) period, the active treatment phase
(6 weeks in both treatment arms), and a 3 week post intervention (post-test)
period, for a total of 12 weeks. The use of daily diaries, and the strain it
might pose on patients has been considered thoroughly and effects are two-fold:
1) patients will be requested to fill in a short daily-diary assessment,
therefore they might feel inconvenienced at some times, 2) on the other hand,
patient-reports suggest that the actual activity of monitoring and describing
their functioning by the end of the day has increased their learning-ability
and increased insights in their own 'Ilness behaviour' favourably, which is
especially helpful in these types of interventions.

The benefits for patients are:
1. Patients will receive continuous feedback on their progress and functioning:
they are to receive weekly individualised treatment feedback from the
treatment-teams in both conditions.
2. Patients will have a chance to receive (in the experimental arm) a new and
promising innovative Tinnitusspecific Behavioural Exposure Treatment (T-BET)
3. Patients in the control arm will be enabled to also receive this T-BET,
after they completed the final follow-up assesment and flow out of the trial.