Rationale for the tinnitus retraining therapy trial

The long-term effect of modulated acoustic stimulation on alteration in EEG brain network of chronic tinnitus patients: An exploratory study

Acoustic stimulation is one of the most influential techniques for distressing tinnitus, while how it functions to reverse neural changes associated with tinnitus remains undisclosed. In this study, our objective is to investigate alterations in brain networks to shed light on the enigma of acoustic intervention for tinnitus. We designed a 75-day long-term acoustic intervention experiment, during which chronic tinnitus patients received daily modulated acoustic stimulation with each session lasting 15 days. Every 15 days, professional tinnitus assessments were conducted, collecting both electroencephalogram (EEG) and tinnitus handicap inventory (THI) data from the patients. Thereafter, we investigated the changes in EEG network organizations during continuous acoustic stimulation and their progressive evolution throughout long-term therapy, alongside exploring the associations between the evolving changes of the network alterations and THI. Our current study findings reveal reorganization in alpha/beta long-range frontal-parietal-occipital connections as well as local frontal and parietal-occipital regions induced by acoustic stimulation. Furthermore, we observed a decrease in modulation effects as therapy sessions progressed. These alterations in brain networks reflect the reversal of tinnitus-related neural activities, particularly distress and perception; thus contributing to tinnitus rehabilitation through long-term modulation effects. This study provides unique insights into how long-term acoustic intervention affects the network organizations of tinnitus patients and deepens our understanding of the pathophysiological mechanisms underlying tinnitus rehabilitation.

Contributions of Counseling and Sound Generator Use in Tinnitus Retraining Therapy: Treatment Response Dynamics Assessed in a Secondary Analysis of a Randomized Trial

PURPOSE

Tinnitus retraining therapy (TRT) has been widely used for 30 years, but its efficacy and the component contributions from counseling and sound therapy remain controversial. The purpose of this secondary analysis from the Tinnitus Retraining Therapy Trial (TRTT) was to compare treatment response dynamics for TRT (counseling and conventional sound generators) with partial TRT (pTRT; counseling and placebo sound generators) and standard of care (SOC; a patient-centered counseling control).

METHOD

The TRTT randomized 151 participants with primary tinnitus (no significant hearing or sound tolerance problems) to TRT, pTRT, or SOC, each of which encouraged use of enriched environmental sound. The primary outcome, mean change in Tinnitus Questionnaire score assessed at baseline and follow-up across 18 months, was normalized for a common baseline and fitted with an exponential model. Time constants were estimated to quantify and compare the treatment response dynamics, which were evaluated for statistical significance using bootstrap analyses.

RESULTS

The change in response to TRT took less time to achieve than that for either pTRT or SOC, as demonstrated by time for normalized Tinnitus Questionnaire scores to decline to 63% and 99% of baseline TRT values: 1.2 months (95% CI [0.2, 1.9]) and 5.7 months (95% CI [0.9, 9.0]), respectively. Corresponding SOC values were 2.7 months (95% CI [1.5, 4.1]) and 12.4 months (95% CI [6.9, 19.0]), while those for pTRT were 2.2 months (95% CI [1.2, 3.4]) and 10.1 months (95% CI [5.7, 15.9]). The differences were significant for TRT versus SOC (p = .020), borderline significant for TRT versus pTRT (p = .057), but nonsignificant for pTRT versus SOC (p = .285). The magnitude of the asymptotic treatment response did not differ significantly among groups.

CONCLUSION

Sound generator use in TRT increases treatment efficiency (beyond any advantage from enriched environmental sound) without affecting treatment efficacy (determined by counseling).

Efficacy of Sound Therapy for Tinnitus Using an Enriched Acoustic Environment with Hearing-Loss Matched Broadband Noise

Background: Tinnitus is a rather heterogeneous chronic condition/disorder which is difficult to treat. Some tinnitus treatments combine sound therapy with counselling. The main goal of this study is to report the efficacy of a customized sound therapy combined with counselling on a cohort of 83 tinnitus patients. Methods: 119 tinnitus subjects, recruited between January 2018 and June 2021, were subjected to a treatment consisting of a combination of an initial counselling session and four-month sound therapy. The sound stimulus was a personalized broadband noise colored by the audiometry of the subjects. These stimuli were given to the patients in mp3 format to be heard 1 h per day over 4 months. The tinnitus severity of the patients was evaluated monthly through the validated Spanish version of the Tinnitus Handicap Inventory. Results: Of the patients, 30% (36 of 119) withdrew from the treatment before finishing, and 96% (80 of 83) of the subjects completing the therapy attained some relief after 4 months. The overall average THI decrease of these 80 participants was 23. However, when the THI was analyzed by severity scales, it was found that patients with initial mild, moderate, severe and catastrophic handicap had an average THI decrease of 14, 20, 31 and 42 points, respectively. Thus, the average THI decrease depended on the baseline severity scale of patients. Conclusions: Consequently, the proposed treatment was demonstrated to be effective in providing clinically relevant relief in tinnitus distress patients in just 4 months.

Neuropsychological monitoring of current acoustic therapies as alternative treatment of chronic tinnitus

At present, the majority of the top tinnitus treatments is based on sound. Sound-based therapies may become highly effective when the right patient at the correct time and the appropriate context is selected. The investigation presented here attempts to compare sound therapies based on music, retraining, neuromodulation, and binaural sounds in line with (1) neuro-audiology assessments and (2) psychological evaluations. Sound-based therapies were applied in 76 volunteers with tinnitus for 60 days. The neuro-audiology assessment was based on the estimation of the approximate entropy of the electrical neural activity. This assessment revealed that the whole frequency structure of the neural networks showed a higher level of activeness in tinnitus sufferers than in control individuals. Then psychological evaluation showed that retraining treatment tended to be the most effective sound-based therapy to reduce tinnitus perception, but it may be not recommended for individuals with anxiety. Binaural sounds and neuromodulation produced very similar effects at reducing tinnitus perception, stress and anxiety. Music treatments can be applied with caution since they may worsen the condition due to their frequency content.

The Tinnitus Retraining Therapy Counseling Protocol as Implemented in the Tinnitus Retraining Therapy Trial

Purpose This clinical focus article is a companion to the work of Erdman et al. (2019), in which we described the rationale, development, and implementation of the standard-of-care protocol used in the Tinnitus Retraining Therapy Trial (TRTT), a multicenter, placebo-controlled, randomized, definitive efficacy trial of tinnitus retraining therapy (TRT). We now describe the historical background, development, and standardized implementation and delivery of the TRT counseling protocol (tinnitus counseling [TC]) used in the TRTT. TC is conjectured to be the key component in the TRT protocol for initiating the habituation process that reduces the response to the tinnitus signal and, ultimately, reduces its impact. In the TRTT, participants assigned to receive TC achieved > 30% reduction in the impact of tinnitus. Method and Results The design and implementation of standardized treatments in multisite randomized controlled trials presents many challenges for investigators. Here, subsequent to presenting the background, rationale, and the TRT protocol model, we describe the development, refinement, and training/certification for standardized delivery of TC in the TRTT. The primary challenges encountered while distilling and streamlining TC for standardized delivery across multiple clinicians and their replacements at six participating military treatment centers in the TRTT are considered, and the resulting counseling protocol is detailed. Conclusions The standardized and streamlined TC used in the TRTT was successful for treating debilitating tinnitus among persons with functionally adequate unaided hearing sensitivity. The structured TC protocol described here appears to be the main determinant of the significant and sizable TRT treatment effects measured in the TRTT, thus bolstering the merits of this standardized counseling approach as one model for the clinical implementation of TRT for the treatment of primary tinnitus.

Correlation Analysis of EEG Brain Network With Modulated Acoustic Stimulation for Chronic Tinnitus Patients

The acoustic stimulation influences of the brain is still unveiled, especially from the brain network point, which can reveal how interaction is propagated and integrated between different brain zones for chronic tinnitus patients. We specifically designed a paradigm to record the electroencephalograms (EEGs) for tinnitus patients when they were treated with consecutive acoustic stimulation neuromodulation therapy for up to 75 days, using the tinnitus handicap inventory (THI) to evaluate the tinnitus severity or the acoustic stimulation treatment efficacy, and the EEG to record the brain activities every 2 weeks. Then, we used an EEG-based coherence analysis to investigate if the changes in brain network consistent with the clinical outcomes can be observed during 75-days acoustic treatment. Finally, correlation analysis was conducted to study potential relationships between network properties and tinnitus handicap inventory score change. The EEG network became significantly weaker after long-term periodic acoustic stimulation treatment, and tinnitus handicap inventory score changes or the acoustic stimulation treatment efficacy are strongly correlated with the varying brain network properties. Long-term acoustic stimulation neuromodulation intervention can improve the rehabilitation of chronic tinnitus patients, and the EEG network provides a relatively reliable and quantitative analysis approach for objective evaluation of tinnitus clinical diagnosis and treatment.

The state of the art of sound therapy for subjective tinnitus in adults

Background:

Sound therapy is a clinically common method of tinnitus management. Various forms of sound therapy have been developed, but there are controversies regarding the selection criteria and the efficacy of different forms of sound therapy in the clinic. Our goal was to review the types and forms of sound therapy and our understanding of how the different characteristics of tinnitus patients influence their curative effects so as to provide a reference for personalized choice of tinnitus sound therapy.

Method:

Using an established methodological framework, a search of six databases including PubMed identified 43 records that met our inclusion criteria. The search strategy used the following key words: tinnitus AND (acoustic OR sound OR music) AND (treatment OR therapy OR management OR intervention OR measure).

Results:

There are various forms of sound therapy, and most of them show positive therapeutic effects. The effect of customized sound therapy is generally better than that of non-customized sound therapy, and patients with more severe initial tinnitus respond better to sound therapy.

Conclusion:

Sound therapy can effectively suppress tinnitus, at least in some patients. However, there is a lack of randomized controlled trials to identify effective management strategies. Further studies are needed to identify the most effective form of sound therapy for individualized therapy, and large, multicenter, long-term follow-up studies are still needed in order to develop more effective and targeted sound-therapy protocols. In addition, it is necessary to analyze the characteristics of individual tinnitus patients and to unify the assessment criteria of tinnitus.

The Tinnitus Retraining Therapy Trial's Standard of Care Control Condition: Rationale and Description of a Patient-Centered Protocol

Purpose The selection and design of control conditions are critical factors in minimizing the influence of unwanted variables in randomized controlled trials (RCTs). This article describes the rationale, design, and content of a standard of care control condition in a Phase III RCT of tinnitus retraining therapy. Method Existing tinnitus practices at military hospitals were identified and aligned with the American Speech-Language-Hearing Association's (2006) preferred practice patterns for tinnitus management and counseling and embedded in a patient-centered protocol to ensure uniformity and treatment fidelity. Results For those involved in the design of behavioral RCTs, the article identifies options and methods to consider in the selection and design of control conditions. Conclusion For those who provide tinnitus services, the standard of care protocol developed for the tinnitus retraining therapy trial constitutes a patient-centered approach to intervention that can be implemented clinically. Supplemental Material https://doi.org/10.23641/asha.9342503.

Effect of Tinnitus Retraining Therapy vs Standard of Care on Tinnitus-Related Quality of Life: A Randomized Clinical Trial

Importance

Tinnitus retraining therapy (TRT) is an internationally recognized, but controversial, protocol of uncertain efficacy that uses tinnitus-specific educational counseling (TC) and sound therapy (ST) to reduce the patient's tinnitus-evoked negative reaction to, and awareness of, tinnitus.

Objective

To compare the efficacy of TRT and its components, ST and TC, with the standard of care (SoC) in reducing the negative effect of tinnitus on quality of life.

Design, Setting, and Participants

A randomized, placebo-controlled, multicenter phase 3 trial was conducted from August 4, 2011, to June 20, 2017, at 6 US military hospitals, the study chairs' office, and a data coordinating center, among 151 active-duty and retired military personnel and dependents with functionally adequate hearing sensitivity and moderate to severe subjective tinnitus. All analyses were based on intention to treat.

Interventions

Central randomized allocation to TRT (TC and ST with conventional sound generators), partial TRT (TC with placebo sound generators), or SoC.

Main Outcomes and Measures

The primary outcome was mean change on the Tinnitus Questionnaire (TQ), assessed longitudinally between baseline and 18 months after start of therapy. The secondary outcomes were changes in TQ subscales, Tinnitus Functional Index (TFI), and Tinnitus Handicap Inventory (THI) total and subscales, as well as a 10-point visual analog scale (VAS).

Results

Among the 151 participants in the study (44 women and 107 men; mean [SD] age, 50.6 [11.3] years), 51 were randomized to receive TRT, 51 to receive partial TRT, and 49 to receive standard of care. Longitudinal analyses showed no difference between partial TRT or TRT compared with SoC, or partial TRT compared with TRT, on TQ, TFI, or THI total scores. Comparison of changes in mean score from baseline to the 18-month visit also showed no difference between treatment groups. Significant improvement was observed at 18 months in all treatment groups on TQ scores for TRT (effect size, -1.32; 95% CI, -1.78 to -0.85), partial TRT (effect size, -1.16; 95% CI, -1.56 to -0.76), and SoC (effect size, -1.01; 95% CI, -1.41 to -0.61). Compared with baseline scores, at 18 months there were reductions in scores by 7 points or more on the TQ score for 86 of 111 participants (77.55%; 95% CI, 69.7%-85.2%), 13 points or more on the TFI for 52 of 111 participants (46.8%; 95% CI, 37.6%-56.1%), 7 points or more on the THI for 63 of 111 participants (56.8%; 95% CI, 47.5%-66.0%), and 2 points or more on the VAS for 45 of 93 participants (48.4%; 95% CI, 38.2%-58.5%).

Conclusions and Relevance

There were few differences between treatment groups. About half of participants showed clinically meaningful reductions in the effect of tinnitus.

Trial Registration

ClinicalTrials.gov identifier: NCT01177137.

Electroencephalographic evaluation of acoustic therapies for the treatment of chronic and refractory tinnitus

Background

To date, a large number of acoustic therapies have been applied to treat tinnitus. The effect that produces those auditory stimuli is, however, not well understood yet. Furthermore, the conventional clinical protocol is based on a trial-error procedure, and there is not a formal and adequate treatment follow-up. At present, the only way to evaluate acoustic therapies is by means of subjective methods such as analog visual scale and ad-hoc questionnaires.

Methods

This protocol seeks to establish an objective methodology to treat tinnitus with acoustic therapies based on electroencephalographic (EEG) activity evaluation. On the hypothesis that acoustic therapies should produce perceptual and cognitive changes at a cortical level, it is proposed to examine neural electrical activity of patients suffering from refractory and chronic tinnitus in four different stages: at the beginning of the experiment, at one week of treatment, at five weeks of treatment, and at eight weeks of treatment. Four of the most efficient acoustic therapies found at the moment are considered: retraining, auditory discrimination, enriched acoustic environment, and binaural.

Discussion

EEG has become a standard brain imaging tool to quantify and qualify neural oscillations, which are basically spatial, temporal, and spectral patterns associated with particular perceptual, cognitive, motor and emotional processes. Neural oscillations have been traditionally studied on the basis of event-related experiments, where time-locked and phase-locked responses (i.e., event-related potentials) along with time-locked but not necessary phase-locked responses (i.e., event-related (de) synchronization) have been essentially estimated. Both potentials and levels of synchronization related to auditory stimuli are herein proposed to assess the effect of acoustic therapies.

Trial registration

Registration Number: ISRCTN14553550. ISRCTN Registry: BioMed Central. Date of Registration: October 31st, 2017.

Structured Counseling for Auditory Dynamic Range Expansion

A structured counseling protocol is described that, when combined with low-level broadband sound therapy from bilateral sound generators, offers audiologists a new tool for facilitating the expansion of the auditory dynamic range (DR) for loudness. The protocol and its content are specifically designed to address and treat problems that impact hearing-impaired persons who, due to their reduced DRs, may be limited in the use and benefit of amplified sound from hearing aids. The reduced DRs may result from elevated audiometric thresholds and/or reduced sound tolerance as documented by lower-than-normal loudness discomfort levels (LDLs). Accordingly, the counseling protocol is appropriate for challenging and difficult-to-fit persons with sensorineural hearing losses who experience loudness recruitment or hyperacusis. Positive treatment outcomes for individuals with the former and latter conditions are highlighted in this issue by incremental shifts (improvements) in LDL and/or categorical loudness judgments, associated reduced complaints of sound intolerance, and functional improvements in daily communication, speech understanding, and quality of life leading to improved hearing aid benefit, satisfaction, and aided sound quality, posttreatment.

The Tinnitus Retraining Therapy Trial (TRTT): study protocol for a randomized controlled trial

Background

Subjective tinnitus is the perception of sound in the absence of a corresponding external sound for which there is no known medical etiology. For a minority of individuals with tinnitus, the condition impacts their ability to lead a normal lifestyle and is severely debilitating. There is no known cure for tinnitus, so current therapy focuses on reducing the effect of tinnitus on the patient’s quality of life. Tinnitus retraining therapy (TRT) uses nonpsychiatric tinnitus-specific educational counseling and sound therapy in a habituation-based protocol to reduce the patient’s tinnitus-evoked negative reaction to, and awareness of, the tinnitus, with the ultimate goal of reducing the tinnitus impact on the patient’s quality of life. Some studies support the efficacy of TRT, but no trial to date has compared TRT with the current standard of care or evaluated the separate contributions of TRT counseling and sound therapy. The Tinnitus Retraining Therapy Trial (TRTT) is a randomized, double-blind, placebo-controlled, multicenter trial for individuals with intolerable tinnitus.

Methods/design

The TRTT is enrolling active-duty and retired military personnel and their dependents with functionally adequate hearing sensitivity and severe tinnitus at US Air Force, Navy, and Army medical centers. Eligible study participants are randomized to TRT, partial TRT, or standard care to determine the efficacy of TRT and its components (TRT counseling and sound therapy). The primary outcome is change in score on the Tinnitus Questionnaire assessed longitudinally between baseline and follow-up (3, 6, 12, and 18 months following treatment). Secondary outcomes include subscale score changes in the Tinnitus Questionnaire, overall and subscale score changes in the Tinnitus Functional Index and Tinnitus Handicap Inventory, and change in the visual analog scale of the TRT Interview Form. Audiological outcomes include tinnitus pitch and loudness match and measures of loudness discomfort levels. The incidence of depression as a safety measure is assessed at each visit using the Beck Depression Inventory Fast Screen.

Trial registration

Clinicaltrials.gov NCT01177137.