Effects of different personalised sound therapies in tinnitus patients with hearing loss of various extents

BACKGROUND

Limited by difficulties in choosing the appropriate sound, sound therapies could only effectively restrain the development of tinnitus in some patients. Thus, individualised sound therapies are of urgent needs.

OBJECTIVE

The purpose of this study was to determine the therapeutic effect of different individualised sound therapies in tinnitus patients complicated with hearing loss of various extents.

RESEARCH DESIGN

Participants were assigned to two different personalised sound therapies as counterbalanced by age and gender in this observational study.

STUDY SAMPLE

Ninety-two tinnitus patients with hearing loss admitted to our hospital from January 2018 to January 2020 were enrolled and evenly grouped as the observation group and the control group in accordance with the random number table.

DATA COLLECTION AND ANALYSES

Tinnitus characteristics of both the groups were determined before treatment. Patients from the observation group received pure tone sound therapy composed of 7 octaves (0.125, 0.25, 0.5, 1, 2, 4 and 8 kHz) based on frequencies determined from their tinnitus characteristics. The control group received pure tone sound therapy composed of 9 one-third octaves based on their tinnitus characteristics.

RESULTS

The observation group had better therapeutic effects than that in the control group (91.30% vs 73.91%, P < .05). After 1 week, and 1- to 3-month treatment, patients in the observation group all presented with decreased tinnitus handicap, decreased tinnitus volume and improved sleep quality compared with the control group (P < .05).

CONCLUSION

This study found that both personalised sound therapies were effective in tinnitus treatment while 7-octave pure tone adjusted from tinnitus frequencies were more promising in decreasing tinnitus handicap and tinnitus volume.

The Influence of Depression, Anxiety and Cognition on the Treatment Effects of Ginkgo biloba Extract EGb 761® in Patients with Tinnitus and Dementia: A Mediation Analysis

Background: Comorbid occurrence of tinnitus and emotional symptoms of anxiety and depression is highly prevalent. The Ginkgo biloba extract EGb 761^® has been shown to be effective in reducing neuropsychiatric symptoms in patients with dementia and tinnitus. Methods: We performed a mediation analysis to evaluate direct effects of EGb 761^® on tinnitus severity, as well as indirect effects mediated by symptoms of depression and anxiety and by changed cognition. We pooled data from subsets of patients suffering from tinnitus that were enrolled in three double-blind, randomized, placebo-controlled clinical trials, which investigated the efficacy of EGb 761^® (240 mg/day for 22–24 weeks) in dementia with concomitant neuropsychiatric symptoms. Results: In total, 594 patients suffered from tinnitus (EGb 761^®, 289; placebo, 305). Direct effects of EGb 761^® on tinnitus severity (p < 0.001) in patients with mild to moderate dementia were found to represent about 60% of the total effect, whereas the indirect effects (p < 0.001) mediated by improvement of anxiety, depression and cognition represented about 40% of the total effect. Conclusions: EGb 761^® could be considered as a supporting treatment for tinnitus in elderly patients suffering from dementia, with added benefit in those with symptoms of depression or anxiety.

Systematic Review on Healthcare and Societal Costs of Tinnitus

Tinnitus disability is a heterogeneous and complex condition, affecting more than 10% and compromising the quality of life of 2% of the population, with multiple contributors, often unknown, and enigmatic pathophysiology. The available treatment options are unsatisfactory, as they can, at best, reduce tinnitus severity, but not eliminate its perception. Given the spread of tinnitus and the lack of a standardized treatment, it is crucial to understand the economic burden of this condition. We conducted a systematic review of the literature on PubMed/MEDLINE, Embase, the Cochrane Database of Systematic Reviews (CDSR) and Google Scholar, in order to identify all the articles published on the economic burden of tinnitus before 1 April 2021 (PROSPERO-International prospective register of systematic reviews-No: CRD42020180438). Out of 273 articles identified through our search strategy, only five articles from studies conducted in the United States of America (USA), the Netherlands and the United Kingdom (UK) provided data on tinnitus's economic costs. Three studies provided mean annual estimates per patient ranging between EUR 1544 and EUR 3429 for healthcare costs, between EUR 69 and EUR 115 for patient and family costs and between EUR 2565 and EUR 3702 for indirect costs, including productivity loss. The other two studies reported an annual mean cost of EUR 564 per patient for tinnitus-related clinical visits, and total costs of EUR 1388 and EUR 3725 for patients treated with a sound generator and Neuromonics Tinnitus Treatment, respectively. Our comprehensive review shows a gap in the knowledge about the economic burden of tinnitus on healthcare systems, patients and society. The few available studies show considerable expenses due to healthcare and indirect costs, while out-of-pocket costs appear to be less financially burdensome. Comprehensive health economic evaluations are needed to fill the gaps in current knowledge, using a unified method with reliable and standardized tools.

Multidisciplinary Tinnitus Research: Challenges and Future Directions From the Perspective of Early Stage Researchers

Tinnitus can be a burdensome condition on both individual and societal levels. Many aspects of this condition remain elusive, including its underlying mechanisms, ultimately hindering the development of a cure. Interdisciplinary approaches are required to overcome long-established research challenges. This review summarizes current knowledge in various tinnitus-relevant research fields including tinnitus generating mechanisms, heterogeneity, epidemiology, assessment, and treatment development, in an effort to highlight the main challenges and provide suggestions for future research to overcome them. Four common themes across different areas were identified as future research direction: (1) Further establishment of multicenter and multidisciplinary collaborations; (2) Systematic reviews and syntheses of existing knowledge; (3) Standardization of research methods including tinnitus assessment, data acquisition, and data analysis protocols; (4) The design of studies with large sample sizes and the creation of large tinnitus-specific databases that would allow in-depth exploration of tinnitus heterogeneity.

Tracking white-matter brain modifications in chronic non-bothersome acoustic trauma tinnitus

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Tractography was compared between two groups of tinnitus and control participants.

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Diffusion was modeled with ss3t-CSD allowing apparent fiber density (AFD) calculation.

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27 bundles of interest were chosen for their link to the auditory and limbic systems.

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AFD was significantly increased in the tinnitus group in the right frontal isthmus.

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AFD in the acoustic radiations was not significantly different between the groups.

Subjective tinnitus is a symptom characterized by the perception of sound with no external acoustic source, most often accompanied by co-morbidities. To date, the specific role of white matter abnormalities related to tinnitus reaches no consensus in the literature. The goal of this study was to explore the structural connectivity related to tinnitus percept per se, thus focusing on a specific population presenting chronic non-bothersome tinnitus of similar etiology (noise induced) without co-morbidities. We acquired diffusion-weighted images with high angular resolution in a homogeneous group of mildly impacted tinnitus participants (n = 19) and their matched controls (n = 19). We focused the study on two subsets of fiber bundles of interest: on one hand, we extracted the acoustic radiation and further included any intersecting fiber bundles; on the other hand, we explored the tracts related to the limbic system. We modeled the diffusion signal using constrained spherical deconvolution. We conducted a deep-learning based tractography segmentation and mapped Apparent Fiber Density (AFD) on the bundles of interest. C, as well as Fractional Anisotropy (FA) and FOD peak amplitude for comparison. Between group statistical comparison was performed along the 27 tracts of interest controlling for confounding hearing loss, tinnitus severity, and duration since onset. We tested a potential correlation with hearing loss, tinnitus duration and tinnitus handicap score along these tracts. In the tinnitus group, we observed increased AFD related to chronic tinnitus percept after acoustic trauma in two main white matter regions. First, in the right hemisphere, in the isthmus between inferior temporal and inferior frontal cortices, in the uncinate fasciculus (UF), and in the inferior fronto-occipital bundle (IFO). Second, in the left hemisphere, underneath the superior parietal region in the thalamo parietal tract and parieto-occipital pontine tract. Between-group differences in the acoustic radiations were not significant with AFD but were with FA. Furthermore, significant correlations with hearing loss were found in the left hemisphere in the inferior longitudinal fasciculus and in the fronto-pontine tract. No additional correlation was found with tinnitus duration nor with tinnitus handicap, as reflected by THI scores. The regions that displayed tinnitus related increased AFD also displayed increased FA. The isthmus of the UF and IFO in the right hemisphere appear to be involved with a number of neuropsychiatric and traumatic disorders confirming the involvement of the limbic system even in chronic non-bothersome tinnitus subjects, potentially suggesting a common pathway between these pathologies. White matter changes underneath the superior parietal cortex found here in tinnitus participants supports the implication of an auditory-somatosensory pathway in tinnitus perception.

Investigating the efficacy of fluoxetine vs. fluoxetine plus alprazolam (single therapy vs. combination therapy) in treatment of chronic tinnitus: A placebo-controlled study

OBJECTIVE

To investigate the effect of combination therapy (fluoxetine + alprazolam) and fluoxetine alone in treatment of tinnitus.

MATERIAL AND METHODS

147 participants with chronic tinnitus were divided into three groups (fluoxetine, fluoxetine+ alprazolam, and placebo). Tinnitus Handicap Inventory (THI), Visual Analogue Scale (VAS), Tinnitus Severity Index (TSI), Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) used to assess tinnitus. Effect size according to partial Eta square calculated and level of significance was considered as P < 0.05.

RESULTS

Fluoxetine reduced VAS, THI, BDI, and increased BAI. The combination therapy significantly reduced VAS, THI, BAI, and BDI. None of them reduced the TSI. The effect size for BAI and BDI were 0.135 (medium) and 0.075 (small), respectively. There was no significant difference between combination and single-drug therapy.

CONCLUSION

Both groups improved THI and VAS. Combination therapy was not significantly different from single-drug treatment. Combination therapy can be considered only according to the psychiatric needs of patients.

A contribution to the debate on tinnitus definition

Tinnitus is generally defined as an auditory perception in the absence of environmental sound stimulation. However, this definition is quite incomplete as it omits an essential aspect, the patient's point of view. This point of view constitutes, first and foremost, a global and unified lived experience, which is not only sensory (localization, loudness, pitch and tone), but also cognitive (thoughts, attentiveness, behaviors) and emotional (discomfort, suffering). This experience can be lived in a very unpleasant way and consequently have a very negative impact on quality of life. This article proposes and justifies a new definition for tinnitus elaborated by a group of French clinicians and researchers, which is more in line with its phenomenology. It also provides a minimum knowledge base, including possibilities for clinical care, hoping to eradicate all misinformation, misconceptions and inappropriate attitudes or practices toward this condition. Here is the short version of our definition: Tinnitus is an auditory sensation without an external sound stimulation or meaning, which can be lived as an unpleasant experience, possibly impacting quality of life.

Development and Evaluation of Portal do Zumbido : A Novel Telehealth Approach to Tinnitus

Introduction  Tinnitus is a prevalent symptom in audiological clinics, and the speech therapist participates in the assessment, diagnosis, and intervention of tinnitus. A range of studies have been developed with the aim to promote auditory health, and telehealth is an option for this purpose. Objective  The aim of the present study was to develop and assess a virtual platform for tinnitus management for speech therapists. Methods  The present study provided a distance-learning-course, with the aid of Portal do Zumbido , available in the following electronic address: zumbido.fob.usp.br. Infographics were available for download, and modules were made to comprise the introduction to the symptoms, assessment, and intervention for tinnitus. Results  Speech therapists of different regions of Brazil received an e-mail invitation to participate and to assess the platform, 46 of whom registered. From the 46 speech therapists registered, 38 assessed the virtual platform with the aid of a questionnaire about the theoretical content and then answered a motivational research sheet (MRS). The speech therapists correctly answered 90% and 100% of the questions in the questionnaire and in the MRS, respectively, which may indicate that the professionals positively absorbed the content; thus, the content was considered to be impressive when the MRS was analyzed. Conclusion   Portal do Zumbido was developed and is available for access in the following electronic address: zumbido.fob.usp.br. Furthermore, the platform received a positive assessment by the speech therapists who participated in the present study.

What's the buzz? The neuroscience and the treatment of tinnitus

Tinnitus is a pervasive public health issue that affects ∼15% of the United States population. Similar estimates have also been shown on a global scale, with similar prevalence found in Europe, Asia, and Africa. The severity of tinnitus is heterogeneous, ranging from mildly bothersome to extremely disruptive. In the United States, ∼10-20% of individuals who experience tinnitus report symptoms that severely reduce their quality of life. Due to the huge personal and societal burden, in the last 20 yr a concerted effort on basic and clinical research has significantly advanced our understanding and treatment of this disorder. Yet, neither full understanding, nor cure exists. We know that tinnitus is the persistent involuntary phantom percept of internally generated nonverbal indistinct noises and tones, which in most cases is initiated by acquired hearing loss and maintained only when this loss is coupled with distinct neuronal changes in auditory and extra-auditory brain networks. Yet, the exact mechanisms and patterns of neural activity that are necessary and sufficient for the perceptual generation and maintenance of tinnitus remain incompletely understood. Combinations of animal model and human research will be essential in filling these gaps. Nevertheless, the existing progress in investigating the neurophysiological mechanisms has improved current treatment and highlighted novel targets for drug development and clinical trials. The aim of this review is to thoroughly discuss the current state of human and animal tinnitus research, outline current challenges, and highlight new and exciting research opportunities.

Efficacy and safety of single- and repeated-selurampanel dosing for 2 weeks in patients with chronic subjective tinnitus: Results of a randomized, double-blind, placebo-controlled, cross-over, proof-of-concept phase IIa study

To evaluate efficacy and safety of BGG492 (selurampanel; an orally active, competitive AMPA glutamate receptor antagonist) in patients with moderate-to-catastrophic chronic subjective tinnitus. Study (NCT01302873) enrolled patients with subjective tinnitus based on THI severity grade 3, 4 or 5 (moderate, severe or catastrophic), and those with chronic (>6 and <36 months) tinnitus. Primary endpoints were clinical status of tinnitus using TBF-12 and tinnitus loudness using VAS after multiple dose 2-week BGG492 treatment. Safety was assessed by recording all adverse events (AEs). After a single dose of BGG492 VAS scores for tinnitus loudness (P=0.012) and tinnitus annoyance (P=0.004) were significantly reduced vs placebo. After 2 weeks treatment a significantly greater proportion of patients showed improvement of ≥4 points from baseline in TBF-12 (stringent responder definition) with BGG492 vs placebo (26.7% [n=23] vs 14% [n=12], respectively; odds ratio [OR] (90% CI):2.30 (1.10, 4.83); P=0.064), fulfilling proof-of-concept achievement criteria. No notable difference in proportion of responders to BGG492 vs placebo was observed as assessed using VAS (26.7% [n=23] vs 27.6% [n=24], respectively; OR (90% CI):0.94 (0.52, 1.67); P=0.848). Dizziness was the most frequently reported AE in 50% [n=21] and 31.5% [n=17] patients on BGG492 100 and 50mg TID, respectively vs 9.6% [n=9] on placebo. In conclusion, BGG492 showed reduction of both tinnitus loudness and annoyance after a single dose and reduction of tinnitus handicap after 2 weeks of treatment in patients with chronic subjective tinnitus, thereby supporting further clinical investigation of AMPA receptor antagonists with an improved benefit/risk ratio. A dose of 100mg TID BGG492 showed higher efficacy but somewhat lower tolerability compared to 50mg TID.

Effects of Low-Level Laser Therapy as a Therapeutic Strategy for Patients With Tinnitus: A Systematic Review

Purpose This systematic review aimed to analyze the effects of low-level laser therapy (LLLT) on the severity of tinnitus when compared to no therapy or other modalities of therapies. Method A systematic review protocol was registered at the International Prospective Register of Systematic Reviews (PROSPERO) under the Registration Number CRD42019119376. A search was performed in each of the following databases: EMBASE, LILACS, PubMed, Science Direct, Scopus, Web of Science, Google Scholar, and ProQuest. The inclusion criteria consisted of studies in adults over 16 years of age, randomized clinical trials in which subjects presented chronic (≥ 6 months) and subjective tinnitus (unilateral or bilateral) as well as with or without bilateral sensorineural hearing loss, and studies that used only LLLT for treatment of tinnitus compared to no-therapy group or other modalities of therapy. No language or time restrictions were stipulated. The references were managed by Endnote Web and Rayyan QCRI. Results After the screening process, seven studies remained that attained the eligibility criteria. Regarding the risk of bias, only one study was categorized as low risk of bias; the six remaining studies were classified as moderate risk of bias. The seven included studies mainly assessed the LLLT effects on tinnitus by Visual Analogue Scale, Tinnitus Handicap Inventory, pitch and loudness matching, minimum masking level, and pure-tone audiometry. All the seven selected studies found different degrees of significant results regarding tinnitus severity; however, there was no consensus among the results. Conclusion Even though the LLLT showed positive effects in the tinnitus severity in some studies, it is not possible yet to make any recommendation over its uses for the treatment of tinnitus severity.

Emerging Topics in the Behavioral Neuroscience of Tinnitus

This volume has highlighted the many recent advances in tinnitus theory, models, diagnostics, therapies, and therapeutics. But tinnitus knowledge is far from complete. In this chapter, contributors to the Behavioral Neuroscience of Tinnitus consider emerging topics and areas of research needed in light of recent findings. New research avenues and methods to explore are discussed. Issues pertaining to current assessment, treatment, and research methods are outlined, along with recommendations on new avenues to explore with research.

Sex-Dependent Aggregation of Tinnitus in Swedish Families

Twin and adoption studies point towards a genetic contribution to tinnitus; however, how the genetic risk applies to different forms of tinnitus is poorly understood. Here, we perform a familial aggregation study and determine the relative recurrence risk for tinnitus in siblings (λs). Four different Swedish studies (N = 186,598) were used to estimate the prevalence of self-reported bilateral, unilateral, constant, and severe tinnitus in the general population and we defined whether these 4 different forms of tinnitus segregate in families from the Swedish Tinnitus Outreach Project (STOP, N = 2305). We implemented a percentile bootstrap approach to provide accurate estimates and confidence intervals for λs. We reveal a significant λs for all types of tinnitus, the highest found being 7.27 (95% CI (5.56-9.07)) for severe tinnitus, with a higher susceptibility in women (10.25; 95% CI (7.14-13.61)) than in men (5.03; 95% CI (3.22-7.01)), suggesting that severity may be the most genetically influenced trait in tinnitus in a sex-dependent manner. Our findings strongly support the notion that genetic factors impact on the development of tinnitus, more so for severe tinnitus. These findings highlight the importance of considering tinnitus severity and sex in the design of large genetic studies to optimize diagnostic approaches and ultimately improve therapeutic interventions.

Adapting Personal Therapies Using a Mobile Application for Tinnitus Rehabilitation: A Preliminary Study

OBJECTIVES

To develop a smartphone application providing sound therapy and cognitive behavioral therapy (CBT) for treating tinnitus and performing a proof-of-concept pilot study evaluating its potential efficacy.

METHODS

An interactive smartphone application available on iOS and Android platforms was developed, which provided an 8-week tinnitus-specific CBT and personalized and frequency-matched sound therapy. Included patients presented to our tertiary clinic between 2017 and 2018, while those waitlisted were regarded as controls. Three surveys were administrated: Tinnitus Handicap Inventory (THI), Generalized Anxiety Disorder 7-item (GAD-7), and Perceived Stress Scale (PSS).

RESULTS

A total of 30 patients enrolled in this study consisting of 20 treatment and 10 control patients and mean age was 55.4 ± 11.6 years. Treatment and control patients had similar age, sex, and pre-enrolment GAD and PSS (all P > .05). Baseline THI scores were also similar between treatment and control cohorts (50.1 ± 21.9 vs 62.0 ± 20.7; P = .15). After 8 weeks, though changes in GAD and PSS scores were similar (P > .05), the treatment group reported a significantly greater improvement in THI scores (17.7 ± 15.8 vs 5.3 ± 10.5, P = .04).

CONCLUSIONS

This pilot study demonstrated potentially promising efficacy of a smartphone-based CBT and sound therapy platform for treating tinnitus and encourages future randomized controlled trials on this treatment modality.

Lidocaine injections to the otic ganglion for the treatment of tinnitus-A pilot study

Tinnitus is defined as the perception of noise without an external acoustic stimulus. Due to the heterogeneity of tinnitus, no treatment has proven equally beneficial to every single of these patients. Previous studies have shown that trigeminal input can interfere with the perception of tinnitus. Therefore, we aimed to explore the therapeutic potential of lidocaine injections in trigeminal structures. We conducted a pilot study with 19 participants to explore feasibility and tolerability of this approach. The intervention consisted of three injections of lidocaine in the anatomical area of the trigeminal ganglion and the ganglion oticum via an oral approach corresponding to the affected side of tinnitus. We performed an assessment that included the Mini-TQ, CGII, and numeric rating scales of tinnitus loudness and severity at different time points over a follow-up period of 12 weeks. In addition to changes of subjective tinnitus complaints, potential adverse events were documented. Patients were treated at the Centre of Otorhinolaryngology in Traunstein, Germany, and data were analyzed at the University of Regensburg, Germany. We did not observe any relevant side effects. There was a significant reduction of tinnitus distress (Mini-TQ, Tinnitus severity) and loudness (measured subjectively) over time. Our pilot data suggests that lidocaine injections targeting trigeminal structures may be able to reduce tinnitus complaints. Future studies should investigate the effects of lidocaine injections in placebo-controlled trials in an extended sample size to further explore the potential benefits of this therapeutic approach on tinnitus.

Impact of personality on acoustic tinnitus suppression and emotional reaction to stimuli sounds

BACKGROUND

Acoustic stimulation was shown to be effective in short-term suppression of tinnitus. However, tinnitus cannot be suppressed in all patients. Recent insights from mental health research suggests that personality traits may be important factors in prediction of treatment outcomes or improvement of tinnitus over time. No previous acoustic stimulation study investigated the effects of personality traits on tinnitus suppression and rating of sound stimuli.

OBJECTIVES

The aim of this study was therefore to examine whether personality is capable to predict tinnitus suppression in chronic tinnitus patients as well as related emotional stimulus evaluation.

METHODS

Personality data (Big Five Index 2; BFI-2) of two acoustic stimulation experiments were pooled for this analysis. Both experiments were conducted at the University of Regensburg, Germany in the time period between April 2018 and October 2019 and consisted of individual designed noise and amplitude modulated tones matched to the participants' tinnitus pitch. Logistic regressions or linear mixed effect models were performed with tinnitus suppression as well as valence and arousal data as dependent variables and BFI-2 personality dimensions as predictors.

RESULTS

28% of the participants showed pronounced short-term tinnitus suppression after acoustic stimulation (50% reduction in subjective tinnitus loudness). Analyzing BFI-2 data, no significant impact of the big five personality traits (neuroticism, agreeableness, extraversion, conscientiousness, openness) were found, neither on acoustic tinnitus suppression, nor on emotional stimulus evaluation, namely arousal.

CONCLUSION

Personality was not shown to be a predictive factor, neither for acoustic stimulation, nor for emotional reaction to stimuli sounds in our studies. However, since tinnitus cannot be suppressed by acoustic stimulation in all patients, future studies should investigate other explaining factors such as patient-related or (neuro)physiological characteristics.

Association between Hyperacusis and Tinnitus

Many individuals with tinnitus report experiencing hyperacusis (enhanced sensitivity to sounds). However, estimates of the association between hyperacusis and tinnitus is lacking. Here, we investigate this relationship in a Swedish study. A total of 3645 participants (1984 with tinnitus and 1661 without tinnitus) were enrolled via LifeGene, a study from the general Swedish population, aged 18-90 years, and provided information on socio-demographic characteristics, as well as presence of hyperacusis and its severity. Tinnitus presence and severity were self-reported or assessed using the Tinnitus Handicap Inventory (THI). Phenotypes of tinnitus with (n = 1388) or without (n = 1044) hyperacusis were also compared. Of 1661 participants without tinnitus, 1098 (66.1%) were women and 563 were men (33.9%), and the mean (SD) age was 45.1 (12.9). Of 1984 participants with tinnitus, 1034 (52.1%) were women and 950 (47.9%) were men, and the mean (SD) age was 47.7 (14.0) years. Hyperacusis was associated with any tinnitus [Odds ratio (OR) 3.51, 95% confidence interval (CI) 2.99-4.13], self-reported severe tinnitus (OR 7.43, 95% CI 5.06-10.9), and THI ≥ 58 (OR 12.1, 95% CI 7.06-20.6). The association with THI ≥ 58 was greater with increasing severity of hyperacusis, the ORs being 8.15 (95% CI 4.68-14.2) for moderate and 77.4 (95% CI 35.0-171.3) for severe hyperacusis. No difference between sexes was observed in the association between hyperacusis and tinnitus. The occurrence of hyperacusis in severe tinnitus is as high as 80%, showing a very tight relationship. Discriminating the pathophysiological mechanisms between the two conditions in cases of severe tinnitus will be challenging, and optimized study designs are necessary to better understand the mechanisms behind the strong relationship between hyperacusis and tinnitus.

Relationship between headaches and tinnitus in a Swedish study

The heterogeneity of tinnitus is likely accounting for the lack of effective treatment approaches. Headaches have been related to tinnitus, yet little is known on how headaches impact tinnitus. We use cross-sectional data from the Swedish Tinnitus Outreach Project to i) evaluate the association between headaches and tinnitus (n = 1,984 cases and 1,661 controls) and ii) investigate the phenotypic characteristics of tinnitus subjects with tinnitus (n = 660) or without (n = 1,879) headaches. In a multivariable logistic regression model, headache was significantly associated with any tinnitus (odds ratio, OR = 2.61) and more so with tinnitus as a big problem (as measured by the tinnitus functional index, TFI ≥ 48; OR = 5.63) or severe tinnitus (using the tinnitus handicap inventory, THI ≥ 58; OR = 4.99). When focusing on subjects with tinnitus, the prevalence of headaches was 26% and reached 40% in subjects with severe tinnitus. A large number of socioeconomic, phenotypic and psychological characteristics differed between headache and non-headache subjects with any tinnitus. With increasing tinnitus severity, fewer differences were found, the major ones being vertigo, neck pain and other pain syndromes, as well as stress and anxiety. Our study suggests that headaches could contribute to tinnitus distress and potentially its severity.

Avenue for Future Tinnitus Treatments

Tinnitus is a common symptom. Standard therapies aim at improving the quality of life and reducing the psychological stress associated with tinnitus. Most interventions have little or no effect on the main symptom. Those affected subjects, however, want such a change and prefer a specific solution, such as pharmacologic therapy to other modalities. Scientific efforts have not yet led to significant improvement in the range of therapies. This article outlines existing efforts and develops ideas on how research for improved tinnitus therapy might look in the future.

Pharmacotherapy of Tinnitus

Tinnitus is a common symptom for which there is in most cases no causal therapy. The search for an improvement of tinnitus through pharmacological interventions has a long tradition. The observation that tinnitus can be transiently suppressed by the use of lidocaine has shown that the symptom is susceptible to pharmacotherapy. So far, however, no medication has been found for either acute or chronic subjective tinnitus that reliably leads to a long-term reduction or even complete disappearance of the symptom for the majority of tinnitus sufferers. Nevertheless, in everyday clinical life, drugs are frequently used, usually off-label, to relieve tinnitus or tinnitus-associated symptoms (e.g. sleep disturbance, depression, anxiety disorder or hearing loss). This chapter shows the different approaches to acute and chronic subjective tinnitus by means of pharmacotherapeutic interventions. Furthermore, this review reports on the scientific studies carried out in this area in recent years and explains the difficulties in finding a suitable medication for most forms of tinnitus. In addition, it reports on the pharmacotherapeutic options for objective tinnitus and describes the development of tinnitus as a side effect of certain drugs. Finally, possible target structures are mentioned, which should possibly be addressed in pharmacological studies in the near future.

Medicines discovery for auditory disorders: Challenges for industry

Currently, no approved medicines are available for the prevention or treatment of hearing loss. Pharmaceutical industry productivity across all therapeutic indications has historically been disappointing, with a 90% chance of failure in delivering a marketed drug after entering clinical evaluation. To address these failings, initiatives have been applied in the three cornerstones of medicine discovery: target selection, clinical candidate selection, and clinical studies. These changes aimed to enable data-informed decisions on the translation of preclinical observations into a safe, clinically effective medicine by ensuring the best biological target is selected, the most appropriate chemical entity is advanced, and that the clinical studies enroll the correct patients. The specific underlying pathologies need to be known to allow appropriate patient selection, so improved diagnostics are required, as are methodologies for measuring in the inner ear target engagement, drug delivery and pharmacokinetics. The different therapeutic strategies of protecting hearing or preventing hearing loss versus restoring hearing are reviewed along with potential treatments for tinnitus. Examples of current investigational drugs are discussed to highlight key challenges in drug discovery and the learnings being applied to improve the probability of success of launching a marketed medicine.

A study on the epidemiology of tinnitus in the United Kingdom

PURPOSE

Subjective tinnitus is a common symptom with potentially negative impact on quality of life. More research is required to gain a deeper understanding of the disease and its clinical presentation. To estimate the incidence of tinnitus and to describe patient-related characteristics such as lifestyle factors and comorbidities.

PATIENTS AND METHODS

Using the Clinical Practice Research Datalink, we calculated incidence rates of first-time diagnosed tinnitus in an adult population between 2000 and 2016. We stratified incidence rates by sex, age, and year of diagnosis. Additionally, we performed a 1:1 matched case-control study comparing body mass index, lifestyle factors and selected comorbidities between patients with incident tinnitus and tinnitus-free controls.

RESULTS

We identified 109 783 adults with a first-time diagnosis of tinnitus between 2000 and 2016, yielding an overall age-standardized incidence rate of 25.0 new tinnitus cases per 10,000 person-years (95% CI: 24.6-25.5). There was a steady increase in tinnitus incidence throughout the study period. Approximately 80% of tinnitus cases were diagnosed at age 40 years or older. We observed the highest incidence rate in individuals aged 60-69 years (41.2 per 10,000 person-years, 95% CI: 40.7-41.7). Smokers and alcohol drinkers were at lower risk of being diagnosed with tinnitus compared with non-smokers and non-drinkers, respectively. The occurrence of tinnitus was strongly associated with a recent diagnosis of several otological and vestibular disorders as well as head and neck disorders.

CONCLUSION

The present observational study found an increasing incidence of tinnitus over time, emphasizing the continuously growing health burden. The findings on patient characteristics, lifestyle factors, and selected comorbidities contribute to a better understanding of risk factors for tinnitus.

Impact of Temporomandibular Joint Complaints on Tinnitus-Related Distress

There is increasing evidence of associations between the presence of temporomandibular joint (TMJ) disorders and tinnitus. It has been recently proposed that tinnitus patients with TMJ complaints could constitute a subtype, meaning a subgroup of tinnitus patients responsive to specific treatments. Tinnitus patients with TMJ complaints are often young women with somatosensory features of their tinnitus. Here, we investigate the socio-economic factors, phenotypic characteristics and psychological variables of tinnitus subjects from the Swedish Tinnitus Outreach Project, with (n = 486) or without (n = 1,996) TMJ complaints. The prevalence of TMJ complaints was greater in tinnitus subjects with severe tinnitus (36%) when compared to those with any tinnitus (19%), strongly indicating the contribution of TMJ problems to the severity of tinnitus. Comparing subgroups with or without TMJ complaints in the whole sample, differences were found regarding a large number of socioeconomic, phenotypic, and psychological characteristics. Subjects with TMJ complaints were more often women, more often reported stress as the cause of tinnitus, were more severely affected by tinnitus, scored worse in measures of psychological well-being and life quality, and were more often affected by problems tolerating sounds, headache, vertigo/dizziness, and neck pain. In addition, they more often reported pulsating and tonal tinnitus, somatic modulation of tinnitus, and aggravation of tinnitus by loud sounds and stress. When focusing the analysis in subjects with tinnitus as a big problem using the Tinnitus Functional Index cut-off ≥ 48, or with severe tinnitus according to the Tinnitus Handicap Inventory cut-off ≥ 58, the impact of somatosensory modulations and stress on tinnitus were greater in subjects with TMJ complaints in comparison to those without. In light of these results, we hypothesize that stress could contribute to the co-occurrence of TMJ problems and tinnitus and also to the development of severe tinnitus. Our study supports the need of involving dental care and stress management in the holistic treatment of patients with severe tinnitus.

Toward Personalized Tinnitus Treatment: An Exploratory Study Based on Internet Crowdsensing

Introduction: Chronic tinnitus is a condition estimated to affect 10–15% of the population. No treatment has shown efficacy in randomized clinical trials to reliably and effectively suppress the phantom perceptions, and little is known why patients react differently to the same treatments. Tinnitus heterogeneity may play a central role in treatment response, but no study has tried to capture tinnitus heterogeneity in terms of treatment response.

Research Goals: To test if the individualized treatment response can be predicted using personal, tinnitus, and treatment characteristics.

Methods: A survey conducted by the web platform Tinnitus Hub collected data of 5017 tinnitus bearers. The participants reported which treatments they tried and the outcome of the given treatment. Demographic and tinnitus characteristics, alongside with treatment duration were used as predictors of treatment outcomes in both an univariate as well as a multivariate regression setup. First, simple linear regressions were used with each of the 13 predictors on all of 25 treatment outcomes to predict how much variance could be explained by each predictor individually. Then, all 13 predictors were added together in the elastic net regression to predict treatment outcomes.

Results: Individual predictors from the linear regression models explained on average 2% of the variance of treatment outcome. “Duration of treatment” was the predictor that explained, on average, most of the variance, 6.8%. When combining all the predictors in the elastic net, the model could explain on average 16% of the deviance of treatment outcomes.

Discussion: By demonstrating that different aspects predict response to various treatments, our results support the notion that tinnitus heterogeneity influences the observed variability in treatment response. Moreover, the data suggest the potential of personalized tinnitus treatment based on demographic and clinical characteristics.

GABAergic and glutamatergic cells in the inferior colliculus dynamically express the GABAAR γ1 subunit during aging

Age-related hearing loss may result, in part, from declining levels of γ-amino butyric acid (GABA) in the aging inferior colliculus (IC). An upregulation of the GABA_AR γ₁ subunit, which has been shown to increase sensitivity to GABA, occurs in the aging IC. We sought to determine whether the upregulation of the GABA_AR γ₁ subunit was specific to GABAergic or glutamatergic IC cells. We used immunohistochemistry for glutamic acid decarboxylase and the GABA_AR γ₁ subunit at 4 age groups in the IC of Fisher Brown Norway rats. The percentage of somas that expressed the γ₁ subunit and the number of subunits on each soma were quantified. Our results show that GABAergic and glutamatergic IC cells increasingly expressed the γ₁ subunit from young age until expression peaked during middle age. At old age (∼77% of life span), the number of GABA_AR γ₁ subunits per cell sharply decreased for both cell types. These results, along with previous studies, suggest inhibitory and excitatory IC circuits may express the GABA_AR γ₁ subunit in response to the age-related decline of available GABA.

Introduction to the Theme “New Therapeutic Targets”

“New Therapeutic Targets” is the theme of articles in the Annual Review of Pharmacology and Toxicology, Volume 59. Reviews in this volume discuss targets for a variety of conditions in need of new therapies, including type 2 diabetes, heart failure with preserved ejection fraction, obesity, thyroid-associated ophthalmopathy, tinnitus, multiple sclerosis, Parkinson's disease and other neurodegenerative diseases, pain, depression, post-traumatic stress disorder, muscle wasting diseases, cancer, and anemia associated with chronic renal disease. Numerous articles in this volume focus on the identification, validation, and utility of novel therapeutic targets, in particular, ones that involve new or unexpected molecular entities. This theme complements several previous themes, including “New Approaches for Studying Drug and Toxicant Action: Applications to Drug Discovery and Development,” “Precision Medicine and Prediction in Pharmacology,” and “New Methods and Novel Therapeutic Approaches in Pharmacology and Toxicology.”