Why Is There No Cure for Tinnitus?

Frontal gamma-alpha ratio reveals neural oscillatory mechanism of attention shifting in tinnitus

In clinical practice, the symptoms of tinnitus patients can be temporarily alleviated by diverting their attention away from disturbing sounds. However, the precise mechanisms through which this alleviation occurs are still not well understood. Here, we aimed to directly evaluate the role of attention in tinnitus alleviation by conducting distraction tasks with multilevel loads and resting-state tests among 52 adults with tinnitus and 52 healthy controls. We demonstrated that the abnormal neural oscillations in tinnitus subjects, reflected in an altered gamma/alpha ratio index in the frontal lobe, could be regulated by attention shifting in a linear manner for which the regulatory effect increased with the load of distraction. Quantitative measures of the regulation significantly correlated with symptom severity. Altogether, our work provides proof-of-concept for the role of attention in tinnitus perception and lays a solid foundation to support evidence-based applications of attention shifting in clinical interventions for tinnitus.

Smartphone-Based Cognitive Behavioral Therapy and Customized Sound Therapy for Tinnitus: A Randomized Controlled Trial

OBJECTIVE

To evaluate the efficacy of a smartphone-based application providing tinnitus-specific cognitive behavioral therapy and customized sound therapy for tinnitus.

METHODS

In a prospective randomized controlled trial, the treatment group participated in daily sound therapy and weekly interactive CBT modules, and the control group did not receive the program (waitlisted). Outcome measures after 8 weeks included the Tinnitus Functional Index (TFI), Generalized Anxiety Disorder (GAD-7), Patient Health Questionnaire (PHQ-9), Perceived Stress Scale (PSS), and Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Ninety-two patients (mean age = 57.2 ± 11.9 years) were included. The treatment (n = 47) and control (n = 45) cohorts had similar TFI, PHQ-9, GAD-7, PSS, and PSQI scores at presentation (all P > .05). Treatment-group patients had significantly higher improvements than controlled patients in their TFI (16.7 ± 14.9 vs 1.9 ± 10.8, P < .001), PHQ-9 (1.9 ± 4.2 vs -0.7 ± 3.4, P = .002), GAD-7 (1.1 ± 3.6 vs -0.9 ± 3.3, P = .009), and PSQI scores (2.5 ± 3.2 vs -1.1 ± 2.1, P < .001). Treatment-group subjects also significantly improved in 7 of the 8 TFI domains (all P < .05). TFI improvements of ≥20 occurred in 18 (38.3%) treatment subjects. Of the 9 treatment-group patients presenting with moderate-severe depression, 4 (44.4%) improved to minimal depression. Of the 4 treatment-group patients with moderate-severe anxiety, 2 (50.0%) improved to minimal anxiety. Of the 17 treatment-group patients with moderate-severe sleep difficulties, 10 (55.6%) had considerable sleep improvement.

CONCLUSION

This novel smartphone application providing cognitive behavioral therapy and customized sound therapy was effective in reducing symptom severity and improving anxiety, sleep, and mood for tinnitus patients.

Effects of tinnitus retraining therapy on patients with tinnitus: a systematic review of randomized controlled trials

PURPOSE

This review aims to explore the influences of tinnitus retraining therapy (TRT) on patients with tinnitus.

METHODS

PubMed, MEDLINE, EMBASE, CINAHL, PEDro, SCOPUS, and Web of Science were screened for randomized controlled trials (RCTs) that explored the effects of TRT on patients with tinnitus from inception to June 30, 2024. The methodological quality of the included RCTs was evaluated using the physiotherapy evidence database (PEDro) scale.

RESULTS

Fifteen studies met our eligibility criteria. A total of 2069 patients with tinnitus (mean age 52.93 years; 66% male) were involved in the present review. The quality of the selected studies ranged from 5 to 8 on the PEDro scale, with a median score of 7. TRT did not provide superior effects in treating patients with tinnitus compared to tinnitus masking (TM), tinnitus educational counselling (TED), TRT with open ear hearing aids, Tailor-made notched music training (TMNMT), partial TRT, usual care, and smart TRT.

CONCLUSIONS

TRT intervention is considered a treatment option for patients with tinnitus. Combining TRT with other interventions, such as cognitive-behavioral therapy, pharmacotherapy, or tDS, may show even greater efficacy. Additional studies are strongly required to recognize the long-term effects of TRT on tinnitus, determine who most likely would benefit from the intervention regarding tinnitus type and severity, and identify the optimal treatment protocol.

A prospective cohort study of cochlear implantation as a treatment for tinnitus in post-lingually deafened individuals

BACKGROUND

Cochlear implants have helped over one million individuals restore functional hearing globally, but their clinical utility in suppressing tinnitus has not been firmly established.

METHODS

In a decade-long study, we examined longitudinal effects of cochlear implants on tinnitus in 323 post-lingually deafened individuals including 211 with pre-existing tinnitus and 112 without tinnitus. The primary endpoints were tinnitus loudness and tinnitus handicap inventory. The secondary endpoints were speech recognition, anxiety and sleep quality.

RESULTS

Here we show that after 24 month implant usage, the tinnitus cohort experience 58% reduction in tinnitus loudness (on a 0-10 scale from 4.3 baseline to 1.8 = -2.5, 95% CI: -2.7 to -2.2, p = 3 x 10-6; effect size d' = -1.4,) and 44% in tinnitus handicap inventory (=-21.2, 95% CI: -24.5 to -17.9, p = 1 x 10-15; d'=-1.0). Conversely, only 3.6% of those without pre-existing tinnitus develop it post-implantation. Prior to implantation, the tinnitus cohort have lower speech recognition, higher anxiety and poorer sleep quality than the non-tinnitus cohort, measured by Mandarin monosyllabic words, Zung Self-rating Anxiety Scale and Pittsburgh Sleep Quality Index, respectively. Although the 24 month implant usage eliminate the group difference in speech and anxiety measures, the tinnitus cohort still face significant sleep difficulties likely due to the tinnitus coming back when the device was inactive at night.

CONCLUSIONS

The present result shows that cochlear implantation can offer an alternative effective treatment for tinnitus. The present result also identifies a critical need in developing always-on and atraumatic devices for tinnitus patients, including potentially those with normal hearing.

Astrocytes and Tinnitus

Tinnitus is correlated with anomalies of neural plasticity and has been found to be affected by inflammatory status. The current theories on tinnitus, although still somewhat incomplete, are based on maladaptive plasticity mechanisms. Astrocytes play a major role in both neural responses to inflammation and plasticity regulation; moreover, they have recently been discovered to encode "context" for neuronal circuits, which is similar to the "expectation" of Bayesian brain models. Therefore, this narrative review explores the possible and likely roles of astrocytes in the neural mechanisms leading to acute and chronic tinnitus.

Effects of Childhood Trauma and Anxiety on the Hypothalamic-Pituitary-Adrenal Axis in Chronic Subjective Tinnitus with Distress

INTRODUCTION

There is some evidence for hypothalamic-pituitary-adrenal (HPA) axis hypofunction in chronic tinnitus, but findings are contradicting possibly due to clinical heterogeneity. This study aimed to assess differential effects of childhood trauma and anxiety on HPA-axis functioning in adults suffering from chronic subjective tinnitus with distress.

METHODS

Salivary cortisol data were collected in 22 chronic subjective tinnitus sufferers (without major depression) and 29 healthy controls after awakening, at baseline, and after a low-dose (0.5 mg) dexamethasone challenge. A factorial ANCOVA was conducted to compare the main effects of group (tinnitus versus. controls), trauma, and their interaction effect on the cortisol awakening response (CAR). Linear mixed models were fitted for baseline and post-dexamethasone cortisol levels with group, sampling time, trauma, and their interactions as fixed factors and subject as the random effect. The Beck Anxiety Index, Anxiety Sensitivity Index, and Panic Disorder Severity Scale were included to investigate effects of anxiety.

RESULTS

A significant interaction between group and trauma (F [1, 47] = 6.9755, p = 0.0112) was found, with the tinnitus group showing lower CARs (M = 5.1808, SD = 0.5821) than the comparison group (M = 5.9974, SD = 0.5251) in traumatized individuals only. No effects were found for baseline or post-dexamethasone cortisol. Anxiety scores had no effects on any of the outcome variables.

CONCLUSION

A differential effect of childhood trauma, but not anxiety, on the HPA-axis function in chronic subjective tinnitus was partly confirmed by the finding of a blunted CAR in tinnitus sufferers reporting early-life adversity.

The Current State of Tinnitus Diagnosis and Treatment: a Multidisciplinary Expert Perspective

Tinnitus, the perception of sound without an external source, affects 15% of the population, with 2.4% experiencing significant distress. In this review, we summarize the current state of knowledge about tinnitus management with a particular focus on the translation into clinical practice. In the first section, we analyze shortcomings, knowledge gaps, and challenges in the field of tinnitus research. Then, we highlight the relevance of the diagnostic process to account for tinnitus heterogeneity and to identify all relevant aspects of the tinnitus in an individual patient, such as etiological aspects, pathophysiological mechanisms, factors that contribute most to suffering, and comorbidities. In the next section, we review available treatment options, including counselling, cognitive-behavioral therapy (CBT), hearing aids and cochlear implants for patients with a relevant hearing loss, sound generators, novel auditory stimulation approaches, tinnitus retraining therapy (TRT), pharmacological treatment, neurofeedback, brain stimulation, bimodal stimulation, Internet- and app-based digital approaches, and alternative treatment approaches. The evidence for the effectiveness of the various treatment interventions varies considerably. We also discuss differences in current respective guideline recommendations and close with a discussion of how current pathophysiological knowledge, latest scientific evidence, and patient perspectives can be translated in patient-centered care.

Ayurvedic Management of Presbycusis (Project TOPMAC): Protocol for an Exploratory Randomized Controlled Trial

BACKGROUND

Presbycusis is characterized by sensorineural hearing loss in both ears at high frequencies, which affects more than half of the older adults by the age of 75 years and is often accompanied by tinnitus and cognitive deterioration. Unfortunately, there are no treatments available to restore hearing loss. Treatment mainly focuses on improving the quality of life and communication with hearing aids. Traditional medicine like Ayurveda also explains ailments of a similar nature as Badhirya and advises using drugs with antiaging and neuroprotective activity for treatment. In Ayurveda, Badhirya and Karnanada (senile deafness with tinnitus) are due to vitiation of Vata Dosha. Treatments such as topical oil pooling (Karnapurana) are usually advised to counter Vata, improve hearing capacity, and reduce tinnitus. Kshirabala Taila, a medicated oil formulation prepared with Sida cordifolia Linnaeus, is one of the most preferred oils for topical oil pooling in such conditions, as it has a definitive indication for sensory dysfunctions. Drugs like Withania somnifera (L.) Dunal (Ashwagandha) are also used, as they ameliorate neurodegeneration and help to improve cognitive dysfunction.

OBJECTIVE

We propose an exploratory randomized controlled trial study for evaluating the efficacy of TOPMAC (Topical Oil Pooling with Kshirabala Taila and Supplementation of Ashwagandha Churna) in tinnitus suppression and hearing and cognitive function protection in patients aged 60-75 years with mild to moderate presbycusis.

METHODS

A parallel, 2-group, exploratory randomized controlled trial will be conducted in an Indian Ayurvedic research center at its outpatient service. Participants (N=60) with mild to moderate presbycusis will be recruited by screening. Participants will be randomized (computer-generated 1:1) to receive either basic treatment and health education (BTHE) or BTHE+TOPMAC for 24 weeks. The primary objective is to compare the efficacy of TOPMAC with that of BTHE in the protection of hearing function. The secondary objective is to compare the efficacy of TOPMAC with that of BTHE in tinnitus suppression and cognitive function protection.

RESULTS

This project was funded in January 2023. The institutional ethics committees at National Ayurveda Research Institute for Panchakarma (3/1/2020/NARIP/Tech/2036) and Institute for Communicative and Cognitive Neuro Sciences (IEC006) approved this study. The first patient was enrolled in September 2023; 22 participants were enrolled as of August 2024. The data analysis is yet to start, and the results are expected to be published by January 2025.

CONCLUSIONS

If this exploratory trial is proven effective, it will steer the setting of a definitive randomized controlled trial to test whether the TOPMAC intervention can be incorporated as a cost-effective integrative approach for managing presbycusis. The Indian government has already launched a National Program for Prevention and Control of Deafness to benefit the deaf population. TOPMAC may later be considered for integration with the national program.

TRIAL REGISTRATION

Clinical Trials Registry India CTRI/2023/04/051485; https://tinyurl.com/2h2hry3n.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/55089.

Effectiveness of Eye Movement Desensitization and Reprocessing-EMDR Method in Patients with Chronic Subjective Tinnitus

This research aimed to investigate the effectiveness of the Eye Movement Desensitization and Reprocessing (EMDR) method on chronic subjective tinnitus. The research was planned as an observational study. The study group comprises individuals who applied to the training and research hospital in Ankara between 2019 and 2020 and were aged between 15 and 60 years old. They were identified as having tinnitus. The study samples were determined as 36 participants selected through purposeful sampling. The samples of the 36 participants included in the study. 12 were assigned to the 1st Group EMDR and Masking Group, 12 to the 2nd Group Masking and EMDR Group, and 12 to the 3rd Control Group. The study's dependent variable was the tinnitus levels of the participants, and the independent variable was EMDR and the Masking method. The dependent variable data of the study was collected with the Visual Analog Scale and Tinnitus Handicap Inventory (THI). EMDR and Masking methods used as independent variables in the study were conducted in eight sessions for two months. As a result of the Wilcoxon Sign test used to determine whether the EMDR Method is effective on tinnitus severity level, the difference between tinnitus severity level pretest and post-test median scores of tinnitus patients was found to be statistically significant. Our research findings show that the EMDR method reduces and improves chronic subjective tinnitus, and further studies with a larger sample size could confirm our results.

Tinnitus Prevalence, Associated Characteristics, and Treatment Patterns among Adults in Saudi Arabia

Tinnitus affects millions of people around the world and causes significant negative impacts on their quality of life (QoL). Tinnitus is rarely examined in Saudi Arabia. This study aimed to estimate the prevalence of tinnitus among adults, explore their experience with tinnitus, investigate the impact of tinnitus on their QoL, and discover their tinnitus management methods. A descriptive cross-sectional study design was performed utilizing a non-probability purposive sampling technique and a face-to-face in-person administered questionnaire. Descriptive statistics and a chi-square test were used to assess the data and find any correlation between the variables. Out of 4860 adults, 320 (males: n = 172; females: n = 148; age range = 18-90 years) had tinnitus, mainly described as a daily, gradual, continuous, whistling, and ringing tinnitus in both ears. Tinnitus prevalence was estimated at 6.54% with a slight predominance in males (6.9%) compared with females (6.2%). Most of the participants were unaware of the cause of their tinnitus. The modal value of the severity of tinnitus signals was severe for both genders. The modal value of the impact of tinnitus on the QoL was moderate for males and severe for females. Sleep, social activities, quiet settings, and concentration were largely affected by tinnitus. Significant associations (p < 0.05) between the impact of tinnitus on the QoL and risk factors, such as gender, age, hearing loss, and hyperacusis were determined. Also, the impact of tinnitus on the QoL was significantly associated (p < 0.05) with the duration of complaints and the severity of tinnitus signals. Approximately, 61% of the participants did not use any tinnitus treatment, while the remaining participants usually used hearing aids, medications, and counseling to manage their tinnitus. By increasing awareness, establishing standard practice, developing guidelines for managing tinnitus, expanding access to suitable interventions, and carrying out additional research, adults living with tinnitus in Saudi Arabia will have better support and, ultimately, an enhancement of their overall well-being.

Identifying tinnitus in mice by tracking the motion of body markers in response to an acoustic startle

Rodent models of tinnitus are commonly used to study its mechanisms and potential treatments. Tinnitus can be identified by changes in the gap-induced prepulse inhibition of the acoustic startle (GPIAS), most commonly by using pressure detectors to measure the whole-body startle (WBS). Unfortunately, the WBS habituates quickly, the measuring system can introduce mechanical oscillations and the response shows considerable variability. We have instead used a motion tracking system to measure the localized motion of small reflective markers in response to an acoustic startle reflex in guinea pigs and mice. For guinea pigs, the pinna had the largest responses both in terms of displacement between pairs of markers and in terms of the speed of the reflex movement. Smaller, but still reliable responses were observed with markers on the thorax, abdomen and back. The peak speed of the pinna reflex was the most sensitive measure for calculating GPIAS in the guinea pig. Recording the pinna reflex in mice proved impractical due to removal of the markers during grooming. However, recordings from their back and tail allowed us to measure the peak speed and the twitch amplitude (area under curve) of reflex responses and both analysis methods showed robust GPIAS. When mice were administered high doses of sodium salicylate, which induces tinnitus in humans, there was a significant reduction in GPIAS, consistent with the presence of tinnitus. Thus, measurement of the peak speed or twitch amplitude of pinna, back and tail markers provides a reliable assessment of tinnitus in rodents.

Effectiveness of Computer-Mediated Educational Counseling for Tinnitus Relief: A Randomized Controlled Trial

Counseling can help alleviate tinnitus-caused emotional distress and correct misconceptions, making it an effective rehabilitation option for people with tinnitus. Advances in communication technology have increased the demand for computer-mediated tinnitus counseling; however, the effectiveness of such counseling in reducing tinnitus is unclear. Thus, this study aimed to determine the tinnitus-relieving effects of computer-mediated counseling. Thirty-six participants with tinnitus were randomly assigned to online counseling (15 participants) or video-based counseling (21 participants) groups, defining how remote counseling was conducted. Tinnitus counseling, comprising 100 items, lasted 2 weeks and was separated into six sessions for the online counseling group and 8-9 items daily for 12 days for the video-based counseling group. The effectiveness of counseling was determined based on score changes between baseline and 2-week follow-up using the Korean version of the Tinnitus Primary Function Questionnaire and Visual Analog Scales for annoyance and loudness. While no significant improvements were observed in other domains, average emotional aspect-related scores showed significant improvements in both groups. Regarding individual results, four and seven participants in the online and video-based counseling groups reported significant improvements in the emotional domain, respectively. Overall, computer-mediated educational counseling might be a rehabilitation option for individuals with tinnitus.

Consecutive Dual-Session Transcranial Direct Current Stimulation in Chronic Subjective Severe to Catastrophic Tinnitus with Normal Hearing

Transcranial direct current stimulation (tDCS) is emerging as a promising non-invasive intervention for tinnitus by aiming to modulate abnormal brain activity. This study investigated the efficacy of dual-session tDCS for the relief of perception, distress, and loudness in patients with severe chronic subjective tinnitus and assessed the duration of tinnitus suppression effects compared to single-session and control groups over a 2-month follow-up. In a prospective, randomized, single-blind, placebo-controlled trial, 30 participants with severe chronic subjective tinnitus underwent bifrontal tDCS. The control group (n = 9), single-session group (n = 10), and dual-session group (n = 11) received 2 mA stimulation for 20 min per session, twice a week for one month. The treatment response was monitored weekly using the Visual Analogue Scale (VAS), with additional assessments using the Tinnitus Handicap Inventory (THI) and Beck Depression Inventory (BDI) at the fourth and eighth weeks. The single- and dual-session groups showed statistically significant improvements in VAS, THI, and BDI scores compared to the control group. THI and BDI scores showed a significant difference between the single- and dual-session groups. The dual-session group demonstrated a more sustained tinnitus suppression effect than the single-session group. tDCS has been validated as an effective intervention for the suppression of tinnitus, with the dual-session protocol showing longer-term benefits. These findings support the potential of tDCS as a treatment for tinnitus, particularly in dual-session applications.

Using Participatory Action Research to Redirect Tinnitus Treatment and Research-An Interview Study

Background: Chronic bothersome tinnitus is a prevalent tinnitus subtype placing a high burden on affected individuals, economies, and healthcare systems. Patient and professional perspectives seem to be partly misaligned on how to improve tinnitus research and treatments in the future. This qualitative interview study was aimed at exploring, comparing, and stipulating the perspectives of different tinnitus stakeholder groups on ways of redirecting research and treatments to reduce patients' suffering while accounting for challenges within these practices. Methods: This study used the participatory action research approach to facilitate the stakeholder involvement. Semi-structured online interviews including five participants (two tinnitus patients, two tinnitus researchers and medical specialists, one general practitioner) were conducted. Inductive grounded theory and the constant comparative method were used for data analysis. Results: Four categories for suggested research adaptations ((I) ethical patient involvement; (II) prioritising cure versus coping research; (III) funding; (IV) ethical publication) and six categories for suggested treatment adaptations ((I) ethical professional support; (II) patient involvement; (III) interdisciplinarity; (IV) professional tinnitus education; (V) clinical treatment guidelines; (VI) psychological treatment) were identified. Participants held partly similar priorities such as increasing pathophysiological and cure research. Differences between participants included, for instance, patients aiming for increasing patient involvement in tinnitus research and treatments compared to professionals arguing that the excessive focus on patients' conditions might reduce the patients' chances of habituating to their symptoms. Conclusions: Four action redirections for improving tinnitus research and treatment practices were defined: (I) facilitating communication between and within stakeholder groups, (II) increasing the reflective use of patient involvement, (III) increasing interdisciplinarity, and (IV) reducing barriers to receiving psychological treatment.

Effectiveness of transcutaneous vagus nerve stimulation for the treatment of tinnitus: an interventional prospective controlled study

OBJECTIVES

The aim of this interventional non-randomised prospective controlled study was to assess the effectiveness of transcutaneous vagus nerve stimulation (tVNS) in human subjects with tinnitus.

DESIGN

The ParasymTM tVNS device was paired with an auditory stimulation. Treatment and observations were conducted over 12 weeks. Audiological evaluation was performed. Responses from a set of questionnaires and quantitative electroencephalography (qEEG) before and after treatment were collected. Voice measurements were done to assess possible side-effects of tVNS.

STUDY SAMPLE

The study involved 29 adults who had chronic tinnitus (15 patients who underwent tVNS paired with sounds and a control group of 14 patients who did not).

RESULTS

In general, subjective and objective measurements of tinnitus showed no improvement in the study group compared to the controls, although certain parameters as gauged by the questionnaires did statistically improve. The loudness and frequency of tinnitus remained the same in both groups. For the qEEG, activity in the theta band increased significantly in the study group compared to the control group.

CONCLUSIONS

The tVNS was not effective in reducing tinnitus symptoms in our study group. However, changes in the theta band suggest there might be cortical effects that might, with sustained treatment, lead to improvements.

Enriched Acoustic Environment as a customized treatment for tinnitus: A non-controlled longitudinal study

Tinnitus is a heterogeneous hearing disorder with no cure at present, but some treatments, such as a combination of counselling and sound therapy, can alleviate the discomfort it causes. The sound therapy efficiency depends on both the type of sound stimulus and the time of exposure. This study describes the fundamentals of a personalized sound therapy that stimulates the auditory system with either continuous or sequential sounds whose spectra are adjusted to the hearing levels of the participants. This sound therapy is called Enriched Acoustic Environment and is assessed in a sample of 137 participants with tinnitus. Tinnitus-related distress relief was clinically relevant and statistically significant for 90% of these patients. This was quantified as a mean decrease of 24.3 points on the Tinnitus Handicap Inventory. 31% of participants were treated with sequential stimuli and achieved greater relief of distress (29.4 points on their Tinnitus Handicap Inventory score) compared to those treated with continuous sound (69%). According to these results, sequential sound seems to be optimal compared to continuous sound.

Objective Neurophysiological Indices for the Assessment of Chronic Tinnitus Based on EEG Microstate Parameters

Chronic tinnitus is highly prevalent but lacks precise diagnostic or effective therapeutic standards. Its onset and treatment mechanisms remain unclear, and there is a shortage of objective assessment methods. We aim to identify abnormal neural activity and reorganization in tinnitus patients and reveal potential neurophysiological markers for objectively evaluating tinnitus. By way of analyzing EEG microstates, comparing metrics under three resting states (OE, CE, and OECEm) between tinnitus sufferers and controls, and correlating them with tinnitus symptoms. This study reflected specific changes in the EEG microstates of tinnitus patients across multiple resting states, as well as inconsistent correlations with tinnitus symptoms. Microstate parameters were significantly different when patients were in OE and CE states. Specifically, the occurrence of Microstate A and the transition probabilities (TP) from other Microstates to A increased significantly, particularly in the CE state (32-37%, p ≤ 0.05 ); and both correlated positively with the tinnitus intensity. Nevertheless, under the OECEm state, increases were mainly observed in the duration, coverage, and occurrence of Microstate B (15-47%, ), which negatively correlated with intensity ( [Formula: see text]-0.513, ). Additionally, TPx between Microstates C and D were significantly reduced and positively correlated with HDAS levels ( [Formula: see text] 0.548, ). Furthermore, parameters of Microstate D also correlated with THI grades ( [Formula: see text]-0.576, ). The findings of this study could offer compelling evidence for central neural reorganization associated with chronic tinnitus. EEG microstate parameters that correlate with tinnitus symptoms could serve as neurophysiological markers, contributing to future research on the objective assessment of tinnitus.

Whole-Body Cryostimulation as an Adjunctive Treatment for Neurophysiologic Tinnitus and Associated Disorders: Preliminary Evidence from a Case Study

BACKGROUND

Tinnitus, which is often associated with reduced quality of life, depression, and sleep disturbances, lacks a definitive treatment targeting its pathophysiological mechanism. Inflammatory markers like TNF-α have been linked to tinnitus, thereby underlining the necessity for innovative therapies. This case study investigates the potential benefits of a multi-approach rehabilitation intervention involving whole-body cryostimulation (WBC) for a 47-year-old male suffering from chronic neurophysiologic tinnitus, who had underwent various unsuccessful treatments from 2005.

METHODS

the patient underwent a personalized, multidisciplinary rehabilitation intervention covering diet, pharmacotherapy, physiotherapy and physical activity classes tailored to the patient's needs and capacities, repetitive transcranial magnetic stimulation (rTMS), and whole-body cryostimulation (WBC).

RESULTS

The adjunctive WBC intervention resulted in a significant progressive improvement in tinnitus severity (tinnitus handicap inventory Δ% = -46.3%, VAS tinnitus score Δ% = -40%). Additional positive outcomes were noted in sleep quality (PSQI Δ% = -41.67%), emotional wellbeing (BDI Δ% = -41.2%), and quality of life (SF-36, WHO-5 Δ% = +16.5).

CONCLUSIONS

This study supports the existing literature suggesting the potential of WBC as an adjunct in a multi-approach intervention in ameliorating tinnitus severity and tinnitus-associated disorders. However, randomized controlled trials in larger populations, which specifically consider WBC's effects on tinnitus, are necessary to confirm these findings and to explore the mechanisms that underlie the observed improvements.

Heterogeneity in response to treatment across tinnitus phenotypes

The clinical heterogeneity of chronic tinnitus poses major challenges to patient management and prompts the identification of distinct patient subgroups (or phenotypes) that respond more predictable to a particular treatment. We model heterogeneity in treatment response among phenotypes of tinnitus patients concerning their change in self-reported health burden, psychological characteristics, and tinnitus characteristics. Before and after a 7-day multimodal treatment, 989 tinnitus patients completed 14 assessment questionnaires, from which 64 variables measured general tinnitus characteristics, quality of life, pain experiences, somatic expressions, affective symptoms, tinnitus-related distress, internal resources, and perceived stress. Our approach encompasses mechanisms for patient phenotyping, visualizations of the phenotypes and their change with treatment in a projected space, and the extraction of patient subgroups based on their change with treatment. On average, all four distinct phenotypes identified at the pre-intervention baseline showed improved values for nearly all the considered variables following the intervention. However, a considerable intra-phenotype heterogeneity was noted. Five clusters of change reflected variations in the observed improvements among individuals. These patterns of treatment effects were identified to be associated with baseline phenotypes. Our exploratory approach establishes a groundwork for future studies incorporating control groups to pinpoint patient subgroups that are more likely to benefit from specific treatments. This strategy not only has the potential to advance personalized medicine but can also be extended to a broader spectrum of patients with various chronic conditions.

Multimodal assessment of tinnitus using functional near-infrared spectroscopy and psychophysiological measures

OBJECTIVE

To use a multimodal approach to classify individuals with tinnitus from controls, and individuals with mild versus severe tinnitus.

DESIGN

We have previously shown feasibility of a non-invasive imaging technique called functional near-infrared spectroscopy (fNIRS) to detect tinnitus-related changes in cortical activity and classify individuals with tinnitus from controls, as well as individuals with mild versus severe tinnitus. In this study we have used a multimodal approach by recording heart rate, heart rate variability and skin conductance, in addition to fNIRS signals, from individuals with tinnitus and controls.

STUDY SAMPLE

Twenty-seven participants with tinnitus and 21 controls were recruited.

RESULTS

Our findings show, addition of heart rate measures can improve accuracy of classifying tinnitus severity, in particular loudness as rated subjectively. The f1-score, a measure of classification accuracy, increased from 0.73 to 0.86 when using a support vector machine classifier for differentiating low versus high tinnitus loudness.

CONCLUSIONS

Subjective tinnitus is a condition that can only be described by the individual experiencing it, as there are currently no objective measures to determine tinnitus presence and severity, or assess the effectiveness of treatments. Objective measurement of tinnitus is a critical step in developing reliable treatments for this debilitating condition.

The potassium channels: Neurobiology and pharmacology of tinnitus

Tinnitus is a widespread public health issue that imposes a significant social burden. The occurrence and maintenance of tinnitus have been shown to be associated with abnormal neuronal activity in the auditory pathway. Based on this view, neurobiological and pharmacological developments in tinnitus focus on ion channels and synaptic neurotransmitter receptors in neurons in the auditory pathway. With major breakthroughs in the pathophysiology and research methodology of tinnitus in recent years, the role of the largest family of ion channels, potassium ion channels, in modulating the excitability of neurons involved in tinnitus has been increasingly demonstrated. More and more potassium channels involved in the neural mechanism of tinnitus have been discovered, and corresponding drugs have been developed. In this article, we review animal (mouse, rat, hamster, and guinea-pig), human, and genetic studies on the different potassium channels involved in tinnitus, analyze the limitations of current clinical research on potassium channels, and propose future prospects. The aim of this review is to promote the understanding of the role of potassium ion channels in tinnitus and to advance the development of drugs targeting potassium ion channels for tinnitus.

Should Tinnitus Patients with Subclinical Hearing Impairment Be Offered Hearing Aids? A Comparison of Tinnitus Mitigation Following 3 Months Hearing Aid Use in Individuals with and without Clinical Hearing Impairment

There is a consensus among tinnitus experts to not recommend hearing aids for tinnitus patients with subclinical hearing impairment. However, this notion is arbitrary, as no previous study has compared the treatment effect of hearing aids on tinnitus distress in patients with and without clinical hearing impairment. In this article, we investigate whether tinnitus patients with clinical and subclinical hearing impairment differ in terms of tinnitus mitigation after hearing aid fitting. Twenty-seven tinnitus patients with either clinical (n = 13) or subclinical (n = 14) hearing impairment were fitted with hearing aids. All participants filled out the tinnitus functional index (TFI) before hearing aid fitting and after 3 months of hearing aid use. Clinically meaningful reductions in tinnitus distress (-13 TFI points or more) were seen in both groups, and the difference in tinnitus mitigation between tinnitus patients with clinical (mean TFI reduction = 17.0 points) and subclinical hearing impairment (mean TFI reduction = 16.9 points) was not statistically significant (p = 0.991). Group differences on the suspected confounding factors of age, sex, time since tinnitus debut, tinnitus distress (TFI score) at baseline, and treatment adherence were statistically insignificant. In light of this, we argue that clinical hearing impairment is not required to achieve meaningful tinnitus mitigation with hearing aids, and that hearing aids could be recommended for tinnitus patients with subclinical hearing impairment.

Effect of Cognitive Rehabilitation by Auditory Stroop Training on Quality of Life of Individuals with Tinnitus

Background: Studies have shown that tinnitus patients have difficulties in cognitive function such as memory and attention. The Stroop task engages the attention network where one aspect of the stimulus is noticed while the other one is ignored. Thus, Stroop training can improve the patient's cognitive control and ability to ignore the tinnitus signal. Method: Thirty chronic tinnitus (> 6 months) patients were included in this study. They were distributed into two 15-member groups: intervention and control. Common audiometric, psychometric, and psychoacoustic evaluations of tinnitus were performed for two groups before intervention and after auditory Stroop training of group 1. Results: There was significant difference in the quality of life and THI scores, VAS of annoyance, and reaction time of Stroop task before and after intervention in group1. The decreased reaction time was positively correlated with improved quality of life, THI score, and VAS of annoyance. Conclusion: Cognitive rehabilitation using tasks such as auditory Stroop can be effective in controlling tinnitus by improving cognitive control.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04011-w.

Somatosensory tinnitus and temporomandibular disorders: A common association

BACKGROUND

Although the association between tinnitus and temporo-mandibular disorders (TMD) has been frequently reported, their rate of association in the literature shows a great variability.

OBJECTIVE

We aimed to investigate the prevalence of TMD in patients with somatosensory tinnitus and, vice versa, the occurrence of somatosensory tinnitus in patients with TMD.

METHODS

The study included patients with somatosensory tinnitus (audiological group) and patients with TMD (stomatological group), evaluated at the audiologic and stomatologic clinics of the Policlinic Hospital of Milan, Italy. Common causes of tinnitus, such as hearing and neurological disorders, were excluded. A cervicogenic somatic tinnitus was also ruled out. Different TMD symptoms, including joint noise and joint pain, were considered. The collected data were analysed using descriptive statistical methods, and the Pearson's Chi-squared test was performed to study the prevalence of the different symptoms by clinical groups.

RESULTS

Audiological group included 47 patients with somatosensory tinnitus. Overall, TMD was diagnosed in 46 patients (97.8%), including TMJ noise in 37 (78.7%), clenching in 41 (87.2%) and pain in 7 (14.8%) patients. Stomatological group included 50 patients with TMD, including joint noise in 32 (64.0%), clenching in 28 (56.0%) and TMJ pain in 42 (84.0%) patients. A somatosensory tinnitus was diagnosed in 12 (24.0%) patients.

CONCLUSION

Our study showed a high prevalence of TMD in patients with tinnitus, as well as a not uncommon occurrence of tinnitus in patients presenting with TMD. The distribution of TMD symptoms, such as joint noise, and joint pain was different between the two groups.

An MR spectroscopy study of temporal areas excluding primary auditory cortex and frontal regions in subjective bilateral and unilateral tinnitus

Previous studies indicate changes in neurotransmission along the auditory pathway in subjective tinnitus. Most authors, however, investigated brain regions including the primary auditory cortex, whose physiology can be affected by concurrent hearing deficits. In the present MR spectroscopy study we assumed increased levels of glutamate and glutamine (Glx), and other Central Nervous System metabolites in the temporal lobe outside the primary auditory cortex, in a region involved in conscious auditory perception and memory. We studied 52 participants with unilateral (n = 24) and bilateral (n = 28) tinnitus, and a control group without tinnitus (n = 25), all with no severe hearing losses and a similar hearing profile. None of the metabolite levels in the temporal regions of interest were found related to tinnitus status or laterality. Unexpectedly, we found a tendency of increased concentration of Glx in the control left medial frontal region in bilateral vs unilateral tinnitus. Slightly elevated depressive and anxiety symptoms were also shown in participants with tinnitus, as compared to healthy individuals, with the bilateral tinnitus group marginally more affected. We discuss no apparent effect in the temporal lobes, as well as the role of frontal brain areas, with respect to hearing loss, attention and psychological well-being in chronic tinnitus. We furthermore elaborate on the design-related and technical obstacles of MR spectroscopy.

[Functional neuroimaging options for tinnitus]

BACKGROUND

The pathophysiology behind tinnitus is still not well understood. Different imaging methods help in the understanding of the complex relationships that lead to the perception of tinnitus.

OBJECTIVE

Herein, different functional imaging methods that can be used in the study of tinnitus are presented.

MATERIALS AND METHODS

Considering the recent literature on the subject, the relevant imaging methods used in tinnitus research are discussed.

RESULTS AND CONCLUSION

Functional imaging can reveal correlates of tinnitus. Due to the still limited temporal and spatial resolution of current imaging modalities, a conclusive explanation of tinnitus remains elusive. With increasing use of functional imaging, additional important insights into the explanation of tinnitus will be gained in the future.

Analysis and comparison of clinical practice guidelines regarding treatment recommendations for chronic tinnitus in adults: a systematic review

OBJECTIVES

To determine if, and to what extent, published clinical practice guidelines for the treatment of chronic tinnitus vary in their recommendations.

DESIGN

Systematic review of guidelines.

DATA SOURCES

PubMed, EMBASE and GIN electronic databases were searched in March 2022 and the search was updated in June 2023.

ELIGIBILITY CRITERIA

We included clinical practice guidelines that gave recommendations on the treatment of tinnitus. No language restrictions were applied.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted the data and used the AGREE checklist to report on reporting.

RESULTS

A total of 10 guidelines were identified and included, published between 2011 and 2021. Recommendations for 13 types of tinnitus treatments were compared. Large differences in guideline development and methodology were found. Seven of the 10 guidelines included a systematic search of the literature to identify the available evidence. Six of the 10 guidelines used a framework for the development of the guideline. Reporting was poor in multiple guidelines. Counselling and cognitive behavioural therapy were the only treatments that were recommended for treating tinnitus associated distress by all guidelines that reported on these topics. Tinnitus retraining therapy, sound therapy, hearing aids and cochlear implantation were not unanimously recommended either due to the lack of evidence, a high risk of bias or judgement of no beneficial effect of the specific treatment.

CONCLUSIONS

There were notable differences with respect to whether guidelines considered the available evidence sufficient enough to make a recommendation. Notably, we identified substantial differences in the rigour of guideline design and development. Reporting was poor in many guidelines. Future guidelines could benefit from the use of reporting tools to improve reporting and transparency and the inclusion of guideline experts and patients to improve the quality of clinical practice guidelines on tinnitus.

Acceptability of Cognitive Behavioral Therapy for Tinnitus: A Study With Veterans and Nonveterans

PURPOSE

Cognitive behavioral therapy (CBT) is a gold standard yet underutilized treatment for tinnitus, and tinnitus is especially highly prevalent among veterans. The aims of this study were twofold: to determine (a) if CBT for tinnitus is underutilized because participants find it less acceptable than other behavioral treatments for tinnitus and (b) if veterans and nonveterans rate behavioral treatments for tinnitus differently.

METHOD

This cross-sectional study was conducted online with a sample of 277 adults in the United States who self-reported at least some level of bothersome tinnitus in the past week. The sample for this study consisted of 129 veterans and 148 nonveterans. Participants read descriptions of CBT, tinnitus retraining therapy (TRT), and mindfulness-based stress reduction (MBSR). For each treatment, presented to them in random order, they provided credibility, expectancy, and acceptability ratings.

RESULTS

Among 277 participants, 147 (53.07%) reporting gender were women, 216 (77.98%) reporting race/ethnicity were White, and 129 (46.57%) were veterans of any branch of the U.S. Armed Forces. Veteran ratings of credibility, expectancy, and acceptability were significantly lower than nonveteran ratings across treatments. There were differences in credibility, expectancy, and acceptability ratings across treatments, and post hoc testing revealed that TRT was consistently rated higher than CBT or MBSR.

CONCLUSIONS

Despite strong research support, CBT was rated as less acceptable than a different, less widely empirically supported treatment. Veterans' ratings of acceptability were lower than those of nonveterans across all treatments.

Development and internal validation of a prediction model for the presence of tinnitus in a Dutch population-based cohort

Objectives

In this study we aim to develop and internally validate a prediction model on tinnitus experience in a representative sample of the Dutch general population.

Methods

We developed a multivariable prediction model using elastic net logistic regression with data from the Dutch Lifelines Cohort Study. This is a multigenerational cohort study on adults who are located in the northern parts of the Netherlands. The model was internally validated using 10-fold cross-validation. The outcome of the model was tinnitus presence, for which we used 24 candidate predictors on different domains (among others demographic, hearing specific, and mental health variables). We assessed the overall predictive performance, discrimination, and calibration of the model.

Results

Data on 122.884 different participants were included, of which 7,965 (6.5%, 0 missing) experienced tinnitus. Nine variables were included in the final model: sex, hearing aids, hearing limitations, arterial blood pressure, quality of sleep, general health, symptom checklist of somatic complaints, cardiovascular risk factors, and age. In the final model, the Brier score was 0.056 and 0.787 in internal validation.

Conclusion

We developed and internally validated a prediction model on tinnitus presence in a multigenerational cohort of the Dutch general population. From the 24 candidate predictors, the final model included nine predictors.

Does it matter what is trained? A randomized controlled trial evaluating the specificity of alpha/delta ratio neurofeedback in reducing tinnitus symptoms

Previous studies showed that alpha/delta ratio neurofeedback was effective in reducing unpleasant psychological, emotional and perceptual consequences of tinnitus. The main goal of the present study was to investigate, whether the specific combination of enhancing alpha frequency band activity and reducing delta frequency band activity was necessary, or merely sufficient, to obtain a positive treatment outcome regarding tinnitus distress and intensity. A second research aim was to assess the relative contribution of neurofeedback-related non-specific and general non-specific effects in neurofeedback treatment. In a three-arm, randomized controlled trial, 94 chronic tinnitus patients were randomly assigned to one of three conditions: alpha/delta ratio neurofeedback (n = 31), beta/theta ratio neurofeedback (n = 28) and non-neurofeedback minimal treatment intervention (n = 35). Neurofeedback participants underwent 10 treatment sessions over a 4-week period. Outcome measures were collected pre-, mid- and post-interventions and at 3-months follow-up. The Tinnitus Handicap Inventory and the Tinnitus Magnitude Index were used as primary outcome measures for tinnitus distress and tinnitus intensity. EEG data recorded during training supplemented primary outcomes. Since data were repeated measures, the analyses used a two-level mixed effects model approach including by-subject random effects (random intercept). For the Tinnitus Handicap Inventory, the results showed no interaction effect. For the Tinnitus Magnitude Index, the analysis showed a significant time × group interaction, indicating that both alpha/delta ratio neurofeedback and beta/theta ratio neurofeedback reported reduced tinnitus intensity. Analysis of EEG data showed a consistent pattern for the alpha/delta ratio over the course of training. Compared to beta/theta ratio neurofeedback, alpha/delta ratio neurofeedback showed an elevated response. Conversely, for the beta ratio to theta ratio, the pattern was more inconsistent, with no clear indication of superiority for beta/theta ratio neurofeedback over alpha/delta ratio neurofeedback. The main question of this piece of research was whether alpha/delta ratio neurofeedback demonstrated frequency band specificity in the alleviation of tinnitus distress and perceived intensity. Results showed that alpha/delta ratio neurofeedback was sufficient but importantly 'not' necessary to achieve a positive outcome on both the Tinnitus Handicap Inventory and Tinnitus Magnitude Index, when compared to beta/theta ratio neurofeedback. Still, the data suggest a trend towards specificity for alpha/delta ratio neurofeedback. Because of this, it may be too premature to discard alpha/delta ratio neurofeedback in the treatment of tinnitus. Recommendations for future studies are outlined.

Seeking Help for Tinnitus and Satisfaction With Healthcare Providers Including Diagnosis, Clinical Services, and Treatment: A Scoping Review

The objective of this scoping review was to describe the extent and type of evidence related to seeking help for tinnitus and satisfaction with healthcare providers including diagnosis, services and treatments along the clinical pathway. The selection criteria were adults aged 18 and over with tinnitus who sought help and where patient satisfaction with healthcare providers was reported. Online databases MEDLINE (OvidSP), Embase (OvidSP), PsycINFO (OvidSP) and CINAHL plus (EBSCO) were searched for original studies in English. The search had no date limit. Twenty-one records were eligible for data extraction. Studies reported that the most common healthcare providers seen were general practitioners, ear, nose and throat specialists and audiologists. Depression and tinnitus severity were related to an increase in the number of times help was sought and the type of healthcare provider seen may also impact patient satisfaction. The majority of participants were unlikely to receive a referral to a specialist at the initial GP consultation. Although there is limited research in this area, help-seekers for tinnitus were generally dissatisfied and reported negative interactions with healthcare providers. However, once in a specialised tinnitus clinical setting, studies reported that most help-seekers were satisfied and had positive interactions with healthcare providers.

Association of Plasma Metabolomic Biomarkers With Persistent Tinnitus: A Population-Based Case-Control Study

Importance

Persistent tinnitus is common, disabling, and difficult to treat.

Objective

To evaluate the association between circulating metabolites and persistent tinnitus.

Design, Setting, and Participants

This was a population-based case-control study of 6477 women who were participants in the Nurses' Health Study (NHS) and NHS II with metabolomic profiles and tinnitus data. Information on tinnitus onset and frequency was collected on biennial questionnaires (2009-2017). For cases, metabolomic profiles were measured (2015-2021) in blood samples collected after the date of the participant's first report of persistent tinnitus (NHS, 1989-1999 and 2010-2012; NHS II, 1996-1999). Data analyses were performed from January 24, 2022, to January 14, 2023.

Exposures

In total, 466 plasma metabolites from 488 cases of persistent tinnitus and 5989 controls were profiled using 3 complementary liquid chromatography tandem mass spectrometry approaches.

Main Outcomes and Measures

Logistic regression was used to estimate odds ratios (ORs) of persistent tinnitus (per 1 SD increase in metabolite values) and 95% CIs for each individual metabolite. Metabolite set enrichment analysis was used to identify metabolite classes enriched for associations with tinnitus.

Results

Of the 6477 study participants (mean [SD] age, 52 [9] years; 6477 [100%] female; 6121 [95%] White individuals) who were registered nurses, 488 reported experiencing daily persistent (≥5 minutes) tinnitus. Compared with participants with no tinnitus (5989 controls), those with persistent tinnitus were slightly older (53.0 vs 51.8 years) and more likely to be postmenopausal, using oral postmenopausal hormone therapy, and have type 2 diabetes, hypertension, and/or hearing loss at baseline. Compared with controls, homocitrulline (OR, 1.32; (95% CI, 1.16-1.50); C38:6 phosphatidylethanolamine (PE; OR, 1.24; 95% CIs, 1.12-1.38), C52:6 triglyceride (TAG; OR, 1.22; 95% CIs, 1.10-1.36), C36:4 PE (OR, 1.22; 95% CIs, 1.10-1.35), C40:6 PE (OR, 1.22; 95% CIs, 1.09-1.35), and C56:7 TAG (OR, 1.21; 95% CIs, 1.09-1.34) were positively associated, whereas α-keto-β-methylvalerate (OR, 0.68; 95% CIs, 0.56-0.82) and levulinate (OR, 0.60; 95% CIs, 0.46-0.79) were inversely associated with persistent tinnitus. Among metabolite classes, TAGs (normalized enrichment score [NES], 2.68), PEs (NES, 2.48), and diglycerides (NES, 1.65) were positively associated, whereas phosphatidylcholine plasmalogens (NES, -1.91), lysophosphatidylcholines (NES, -2.23), and cholesteryl esters (NES,-2.31) were inversely associated with persistent tinnitus.

Conclusions and Relevance

This population-based case-control study of metabolomic profiles and tinnitus identified novel plasma metabolites and metabolite classes that were significantly associated with persistent tinnitus, suggesting that metabolomic studies may help improve understanding of tinnitus pathophysiology and identify therapeutic targets for this challenging disorder.

Efficacy and factors influencing outcomes of customized music therapy combined with a follow-up system in chronic tinnitus patients

BACKGROUNDS

Tinnitus is a meaningless sound signal perceived by the patients in the absence of auditory stimuli. Due to the complex etiology and unclear mechanism, specific therapies for tinnitus are still in the exploratory stage. In recent years, personalized and customized music therapy has been proposed as an effective method for tinnitus treatment. The aim of this study was to explore the efficacy of customized therapy with a well-designed follow-up system in the treatment of tinnitus through a large sample one arm study and to identify the relevant factors affecting the treatment outcome.

METHODS

The study investigated a total of 615 patients with unilateral or bilateral chronic tinnitus who received personalized and customized music therapy for 3 months. A complete follow-up system was designed by the professionals. Questionnaires of Tinnitus Handicap Inventory (THI), Hospital Anxiety and Depression Scale (HADS) and Visual Analogue Scale (VAS) were used to evaluate the therapeutic effects and relevant factors affecting the efficacy of therapy.

RESULTS

The results showed a decreasing trend in THI and VAS scores after 3 months of therapy, with statistically significant differences between pre- and post-therapy time points (P < 0.001). All patients were divided into 5 groups according to THI scores, and the mean reduction score in catastrophic, severe, moderate, mild and slight group was 28, 19, 11, 5, 0 respectively. The proportion of tinnitus patients with anxiety was higher than that with depression (70.57% and 40.65%, respectively), and there were statistically significant differences between HADS-A/D scores pre- and post-therapy. Binary logistic regression showed that the baseline of THI, VAS scores, the duration of tinnitus and the state of anxiety prior to therapy were significant influencing factors of therapeutic efficacy.

CONCLUSIONS

The magnitude of reduction in THI scores after music therapy depended on the severity of the patients' tinnitus, the higher the initial THI scores, the greater the potential for improvement in tinnitus disorders. Music therapy also reduced the anxiety and depression levels of tinnitus patients. Therefore, personalized and customized music therapy with a comprehensive follow-up system may be an effective treatment option for chronic tinnitus patients.

REM Sleep Impairment May Underlie Sleep-Driven Modulations of Tinnitus in Sleep Intermittent Tinnitus Subjects: A Controlled Study

(1) Background: Poor sleep and fragmented sleep are associated with several chronic conditions. Tinnitus is an auditory symptom that often negatively combines with poor sleep and has been associated with sleep impairment and sleep apnea. The relationship between tinnitus psychoacoustic characteristics and sleep is still poorly explored, notably for a particular subgroup of patients, for whom the perceived loudness of their tinnitus is highly modulated by sleep. (2) Methods: For this observational prospective study, 30 subjects with tinnitus were recruited, including 15 "sleep intermittent tinnitus" subjects, who had reported significant modulations of tinnitus loudness related to night sleep and naps, and a control group of 15 subjects displaying constant non-sleep-modulated tinnitus. The control group had matching age, gender, self-reported hearing loss grade and tinnitus impact on quality of life with the study group. All patients underwent a polysomnography (PSG) assessment for one complete night and then were asked to fill in a case report form, as well as a report of tinnitus loudness before and after the PSG. (3) Results: "Sleep Intermittent tinnitus" subjects had less Stage 3 sleep (p < 0.01), less Rapid-Eye Movement (REM) Sleep (p < 0.05) and more Stage 2 sleep (p < 0.05) in proportion and duration than subjects from the control group. In addition, in the "sleep Intermittent tinnitus" sample, a correlation was found between REM sleep duration and tinnitus overnight modulation (p < 0.05), as well as tinnitus impact on quality of life (p < 0.05). These correlations were not present in the control group. (4) Conclusions: This study suggests that among the tinnitus population, patients displaying sleep-modulated tinnitus have deteriorated sleep quality. Furthermore, REM sleep characteristics may play a role in overnight tinnitus modulation. Potential pathophysiological explanations accounting for this observation are hypothesized and discussed.

A Heterogeneous Sample of a Spanish Tinnitus Cohort

Taking into account heterogeneity has been highly recommended in tinnitus studies both to disentangle all diverse factors that can contribute to their complexity and to design personalized treatments. To this aim, a heterogeneous sample of 270 tinnitus subjects is analyzed considering the gender (male/female), hearing condition (hearing-impaired/normal-hearing), and tinnitus severity (compensated/decompensated) subgroups. Two categorical variables (tinnitus laterality and tinnitus sound type) and four quantitative variables (average auditory threshold, age of tinnitus onset, tinnitus frequency, and tinnitus severity) are used. The percentages (for categorical variables) and mean values (for quantitative variables) of the whole sample are compared with these of each subgroup. Furthermore, correlational and hypothesis testing is applied to calculate the correlation coefficients and statistical significance, respectively. The results show that the male and female subgroups contrast in the sound type and frequency of their tinnitus, hearing-impaired and normal-hearing individuals differ, in addition, in their average auditory threshold, and the compensated/decompensated tinnitus subgroup provides significantly distinct values in tinnitus laterality and tinnitus sound.

Comparing Clustering Methods Applied to Tinnitus within a Bootstrapped and Diagnostic-Driven Semi-Supervised Framework

The understanding of tinnitus has always been elusive and is largely prevented by its intrinsic heterogeneity. To address this issue, scientific research has aimed at defining stable and easily identifiable subphenotypes of tinnitus. This would allow better disentangling the multiple underlying pathophysiological mechanisms of tinnitus. In this study, three-dimensionality reduction techniques and two clustering methods were benchmarked on a database of 2772 tinnitus patients in order to obtain a reliable segmentation of subphenotypes. In this database, tinnitus patients' endotypes (i.e., parts of a population with a condition with distinct underlying mechanisms) are reported when diagnosed by an ENT expert in tinnitus management. This partial labeling of the dataset enabled the design of an original semi-supervised framework. The objective was to perform a benchmark of different clustering methods to get as close as possible to the initial ENT expert endotypes. To do so, two metrics were used: a primary one, the quality of the separation of the endotypes already identified in the database, as well as a secondary one, the stability of the obtained clusterings. The relevance of the results was finally reviewed by two ENT experts in tinnitus management. A 20-cluster clustering was selected as the best-performing, the most-clinically relevant, and the most-stable through bootstrapping. This clustering used a T-SNE method as the dimensionality reduction technique and a k-means algorithm as the clustering method. The characteristics of this clustering are presented in this article.

Tinnitus and treatment-resistant depression

Tinnitus, a frequent disorder, is the conscious perception of a sound in the absence of a corresponding external acoustic sound source in the sense of a phantom sound. Although the majority of people who perceive a tinnitus sound can cope with it and are only minimaly impaired in their quality of lfe, 2-3% of the population perceive tinnitus as a major problem. Recently it has been proposed that the two groups should be differentiated by distict terms: "Tinnitus" describes the auditory or sensory component, whereas "Tinnitus Disorder" reflects the auditory component and the associated suffering. There is overwhelming evidence that a high tinnitus burden is associated with the increased occurrence of comorbidities, including depression. Since no causal therapeutic options are available for patients with tinnitus at the present time, the identification and adequate treatment of relevant comorbidities is of great importance for the reduction of tinnitus distress. This chapter deals with the relationship between tinnitus and depression. The neuronal mechanisms underlying tinnitus will first be discussed. There will also be an overview about depression and treatment resistant depression (TRD). A comprehensive review about the state-of-the-art evidences of the relationship between tinnitus and TRD will then be provided.

Is There an Optimal Repetitive Transcranial Magnetic Stimulation Target to Treat Chronic Tinnitus?

OBJECTIVE

Chronic tinnitus is a clinical symptom that affects 10% to 15% of the adult population. Repetitive transcranial magnetic stimulation (rTMS) is a promising treatment, but significant heterogeneity exists in the treatment outcomes and stimulation parameters. In this study, we perform a qualitative systematic review to determine if there is an optimal rTMS site to treat tinnitus.

DATA SOURCES

A literature search was performed by searching the MEDLINE, Embase, Web of Science, and Cochrane databases.

REVIEW METHODS

Sham-controlled studies in adults were included that contained >10 patients with tinnitus for >3 months and utilized 10 to 20 electroencephalography coordinates. Study outcomes were considered positive if the treatment arm reported a significant reduction in the primary tinnitus score relative to sham.

RESULTS

There were 1211 studies screened. Nineteen studies met the inclusion criteria, and 8 unique stimulation sites were reported. Studies had 53.7 ± 46.0 patients (mean ± SD). The mean duration of follow-up was 10.3 ± 9.6 weeks. Positive outcomes regarding tinnitus suppression were reported in 5 of 5 (100%) studies stimulating the temporoparietal junction midway between T3 and P3 or between T4 and P4. Tinnitus suppression at all other sites was less frequent with a combined success rate of only 8 of 14 (57.1%).

CONCLUSION

Significant heterogeneity exists in the literature in regard to the optimal transcranial magnetic stimulation target. These preliminary findings suggest that the temporoparietal junction midway between T3 and P3 or T4 and P4 is a promising nonauditory rTMS target in the setting of chronic tinnitus. Future research should elucidate the effectiveness of this site for tinnitus suppression.

Combined Bifrontal Transcranial Direct Current Stimulation and Auditory Stroop Training in Chronic Tinnitus

Patients with tinnitus experience difficulties in cognitive control and executive functions. Many of which are regarded as the cause of tinnitus rather than its complications. Methods for the improvement of inhibitory and cognitive control seem to be effective in the control of tinnitus. In this study, transcranial direct current stimulation and auditory Stroop exercise were have been to improve inhibitory control and the ability to ignore tinnitus in patients suffering from chronic tinnitus. 34 patients with chronic tinnitus (> 6 months) were randomly divided into two groups. The first group consist of 17 patients who received 6 sessions of tDCS followed by 6 sessions of auditory Stroop training. The second group received 6 sessions of sham tDCS followed by 6 sessions of auditory Stroop training. The initial evaluations including pure tone audiometry, psychoacoustic measurements, tinnitus handicap inventory (THI) survey and visual analog scale (VAS) of annoyance and loudness were performed before, immediately after, and one month after the tDCS, sham, and Stroop training. The results of this study revealed a significant reduction in THI score, VAS of loudness, and annoyance of tinnitus. A significant correlation was detected between the reaction time of incongruent words in the Stroop task and improvement of THI score and VAS of annoyance. Combined tDCS and Stroop training efficiently improve chronic tinnitus.

Tinnitus and distress: an electroencephalography classification study

There exist no objective markers for tinnitus or tinnitus disorders, which complicates diagnosis and treatments. The combination of EEG with sophisticated classification procedures may reveal biomarkers that can identify tinnitus and accurately differentiate different levels of distress experienced by patients. EEG recordings were obtained from 129 tinnitus patients and 142 healthy controls. Linear support vector machines were used to develop two classifiers: the first differentiated tinnitus patients from controls, while the second differentiated tinnitus patients with low and high distress levels. The classifier for healthy controls and tinnitus patients performed with an average accuracy of 96 and 94% for the training and test sets, respectively. For the distress classifier, these average accuracies were 89 and 84%. Minimal overlap was observed between the features of the two classifiers. EEG-derived features made it possible to accurately differentiate healthy controls and tinnitus patients as well as low and high distress tinnitus patients. The minimal overlap between the features of the two classifiers indicates that the source of distress in tinnitus, which could also be involved in distress related to other conditions, stems from different neuronal mechanisms compared to those causing the tinnitus pathology itself.

Low Evidence for Tinnitus Risk Factors: A Systematic Review and Meta-analysis

AIMS/HYPOTHESIS

Identifying risk factors for tinnitus could facilitate not only the recommendations for prevention measures, but also identifying potential pathways for new interventions. This study reports the first comprehensive systematic review of analytical observational studies able to provide information about causality (i.e., case-control and cohort designs).

METHODS

A literature search of four electronic databases identified epidemiological studies published on tinnitus and different exposures. Independent raters screened all studies, extracted data, and evaluated study quality using the Newcastle-Ottawa Scale. Reported relative risks (RR), hazard ratios (HR), odds ratios (OR), and prevalence ratios (PR) with 95% confidence intervals (CI) were used to compute crude estimates of RR for tinnitus risk factors.

RESULTS

From 2389 records identified, a total of 374 articles were read as full text (24 reviews, 301 cross-sectional studies, 42 cohort studies, and 7 case-control studies). However, from 49 case-control and cohort studies, only 25 adequately reported risk ratios. Using the findings from these studies, positive causal associations were found for various hearing-related factors (i.e., unspecified hearing loss, sensorineural hearing loss, occupational noise exposure, ototoxic platinum therapy, and otitis media). Evidence was also found for a number of non-otological risk factors including temporo-mandibular joint disorder, depression, chronic obstructive pulmonary disease, and hyperlipidemia. Negative associations indicating preventative effects were found for diabetes and high alcohol consumption. No associations were found for low alcohol consumption, body mass index, head injury, heart failure, hypertension, leisure noise exposure, migraine, rheumatoid arthritis, sex, smoking, stroke, and whiplash. However, with the exception of unspecified hearing loss, these findings resulted from pooling no more than 4 studies, illustrating that the vast majority of the associations still remain inconclusive.

CONCLUSIONS

These systematic review and meta-analysis confirm a number of otological and non-otological risk factors for tinnitus. By highlighting major gaps in knowledge, our synthesis can help provide direction for future research that will shed light on the pathophysiology, improve management strategies, and inform more effective preventions.

Prediction Models for Tinnitus Presence and the Impact of Tinnitus on Daily Life: A Systematic Review

The presence of tinnitus does not necessarily imply associated suffering. Prediction models on the impact of tinnitus on daily life could aid medical professionals to direct specific medical resources to those (groups of) tinnitus patients with specific levels of impact. Models of tinnitus presence could possibly identify risk factors for tinnitus. We systematically searched the PubMed and EMBASE databases for articles published up to January 2021. We included all studies that reported on multivariable prediction models for tinnitus presence or the impact of tinnitus on daily life. Twenty-one development studies were included, with a total of 31 prediction models. Seventeen studies made a prediction model for the impact of tinnitus on daily life, three studies made a prediction model for tinnitus presence and one study made models for both. The risk of bias was high and reporting was poor in all studies. The most used predictors in the final impact on daily life models were depression- or anxiety-associated questionnaire scores. Demographic predictors were most common in final presence models. No models were internally or externally validated. All published prediction models were poorly reported and had a high risk of bias. This hinders the usability of the current prediction models. Methodological guidance is available for the development and validation of prediction models. Researchers should consider the importance and clinical relevance of the models they develop and should consider validation of existing models before developing new ones.

Tinnitus Prevalence and Associated Factors among Dental Clinicians in the United Arab Emirates

Dental clinicians are at increased risk for developing tinnitus due to exposure to high levels of occupational noise. This study aimed to determine tinnitus prevalence and associated factors among dental clinicians. Interviews were conducted with 150 randomly selected dental clinicians using a questionnaire. Noise levels were measured at three points of time at the operating area. Tinnitus was reported in 19.33% of the participants. The average noise level was significantly higher among participants with tinnitus compared to those without the condition. More participants complained of intermittent tinnitus and the rest had the constant type, with the latter being significantly more bothersome. The weekly average time of using high-speed handpieces, suction and electric handpieces, age and experience had a significant effect on the presence of tinnitus. Only 2.7% of the participants reported the use of a hearing protection device. Tinnitus is a common finding among dental clinicians especially those with higher levels of occupational noise and more frequent use of noise-generating equipment. Knowledge of tinnitus prevalence aids in realizing the extent of its impact and making informed decisions. These results call for improved awareness of the negative impact of clinically-generated noise and emphasize the importance of preventive measures and periodic audiometry exams.

Evaluation and Management of Tinnitus: Are There Opportunities for Improvement?

OBJECTIVE

To review current information about diagnosis and management of tinnitus aiming to identify opportunities for achieving a cost-effective, efficient, evidence-based approach that meets the needs of tinnitus sufferers.

DATA SOURCES

PubMed/MEDLINE.

REVIEW METHODS

In total, 249 relevant published reports were reviewed. Pertinent keywords and MeSH terms identified reports via PubMed and EMBASE. Acknowledged experts were consulted on ways to improve tinnitus management.

CONCLUSIONS

There may be opportunities to improve evaluation and management of patients with tinnitus using modern modes of communication and a multidisciplinary therapeutic approach.

IMPLICATIONS FOR PRACTICE

Tinnitus can adversely affect quality of life while being time-consuming and costly to evaluate and manage. Based on both personal experience and the reports of others, patients with tinnitus who choose to see a physician primarily want to know two things: (1) that the tinnitus that is so distressing will not remain at the same level of severity forever and (2) that something can be done to help cope with the tinnitus that is so annoying. Recent advancements in internet communications, social media, information technology, artificial intelligence, machine learning, holistic medical care, mind-body integrative health care, and multidisciplinary approaches in medical therapeutics may be possibly making new ways of meeting the needs of patients with tinnitus.

A triple blind, placebo controlled, randomised controlled trial of betahistine dihydrochloride in the treatment of primary tinnitus

OBJECTIVES

To evaluate the effectiveness of betahistine in the treatment of primary tinnitus.

DESIGN

To evaluate the effectiveness of betahistine in the treatment of primary tinnitus.

SETTING

Universidade estadual Paulista Julio de Mesquita Filho, Botucatu Medical School, São paulo, Brazil.

PARTICIPANTS

Adult patients with primary tinnitus who had not undergone treatment for tinnitus in the last 6 months were included. Patients with profound sensorineural deafness, hearing aid users and patients with metabolic, neurological, psychiatric or decompensated cardiovascular diseases were excluded.

STUDY GROUPS

in the betahistine group, patients received betahistine 24 mg every 12 h for 90 days; in the control group, patients received placebo tablets every 12 h for 90 days.

MEAN OUTCOME MEASURES

Primary outcome measure: Tinnitus Handicap Inventory (THI).

SECONDARY OUTCOME MEASURES

Clinical Global Impression Improvement (CGI-I) and a question of 'Yes' or 'No' to participants about their perception of improvement in symptoms.

RESULTS

Of 284 participants initially identified, 62 were randomised (betahistine group n = 31; control group n = 31). Median age (IQR) 54 (48-60) years, with a balanced number of men and women. There was no difference in THI outcome between the study groups (median difference, -2 points; 95% CI, -8 to 6 points); the THI after the intervention was a median (IQR) 4 (-4 to 14) lower points in the betahistine group, and a median (IQR) 2 (-6 to 10) in the control group. There was no statistical difference in secondary outcome measures. Adverse events were mild and there was no statistical difference between groups.

CONCLUSIONS

Betahistine dihydrochloride was ineffective in the treatment of primary tinnitus in adults.

Comparison of Tinnitus Handicap Inventory and Tinnitus Functional Index as Treatment Outcomes

BACKGROUND

Tinnitus is an audiological disorder for which there are no objective measuring tools. Thus, many self-report questionnaires have been proposed to assess its severity. These questionnaires have been judged for their capacity to assess the tinnitus severity at baseline, their sensitivity to treatment-related changes (responsiveness), and their resolution.

METHODS

The most widely used questionnaires for clinical and research studies are the Tinnitus Handicap Inventory (THI) and the Tinnitus Functional Index (TFI). While both questionnaires have been recognized as good evaluators of the baseline tinnitus severity, the latter is considered to be more responsive to changes following treatments.

OBJECTIVES

The aim of this work is to provide a preliminary comparison of the performance of both questionnaires in the initial and final tinnitus severity assessment of a cohort of patients undergoing a four-month Enriched Acoustic Environment (EAE) therapy.

RESULTS

The EAE therapy provided a 30 and 26 point reduction in THI and TFI, respectively. A good correlation is obtained between the THI and TFI questionnaires at baseline and after the treatment.

CONCLUSION

At baseline, the THI provided a higher score than the TFI for a higher degree of tinnitus but a lower score for lower tinnitus severity. Both THI and TFI were good questionnaires for baseline assessment and for treatment-related changes. The THI provided a slightly higher score drop than the TFI following the treatment, although the TFI had better resolution.

Categorization of tinnitus listeners with a focus on cochlear synaptopathy

Tinnitus is a complex and not yet fully understood phenomenon. Often the treatments provided are effective only for subgroups of sufferers. We are presently not able to predict benefit with the currently available diagnostic tools and analysis methods. Being able to identify and specifically treat sub-categories of tinnitus would help develop and implement more targeted treatments with higher success rate. In this study we use a clustering analysis based on 17 predictors to cluster an audiologically homogeneous group of normal hearing participants, both with and without tinnitus. The predictors have been chosen to be either tinnitus-specific measures or measures that are thought to be connected to cochlear synaptopathy. Our aim was to identify a subgroup of participants with characteristics consistent with the current hypothesized impact of cochlear synaptopathy. Our results show that this approach can separate the listeners into different clusters. But not in all cases could the tinnitus sufferers be separated from the control group. Another challenge is the use of categorical measures which seem to dominate the importance analysis of the factors. The study showed that data-driven clustering of a homogeneous listener group based on a mixed set of experimental outcome measures is a promising tool for tinnitus sub-typing, with the caveat that sample sizes might need to be sufficiently high, and higher than in the present study, to keep a meaningful sample size after clustering.

Measuring tinnitus in pharmaceutical clinical trials

This paper reviews methods and considerations for measuring tinnitus in clinical trials designed to evaluate treatment options using investigational medicinal products. Tests applied in tinnitus-related research and clinical practice have their own measurement purposes, advantages, and limitations. If the characteristics of each test method are well understood, the test can be effectively used in clinical trials. For the accuracy of clinical trial results, it is necessary to use a test tool with verified validity, reliability, and sensitivity. If a test tool that is likely to have high variability in the same individual is required in the clinical trial, strategies to increase the reliability of the test, such as repeat measurements, may also be needed. In addition, a test tool that meets the purpose of the clinical trial should be selected. For example, the tinnitus questionnaire is appropriate to assess reactions to tinnitus, and measurements of tinnitus loudness or pitch are appropriate to evaluate the psychoacoustic characteristics of tinnitus. In conclusion, the use of validated test tools that meet the purpose of the trial will help with the accuracy of the clinical trial results.

Testing A Hypothesis: Tinnitus Control by Enhancing Physiological Inhibition

Background

Deficit in cognitive functions and central executive function is one of the popular hypotheses on the underlying cause of tinnitus. Some studies expressed the effect of tinnitus on the inhibitory cognitive tasks, referring to the slower inhibitory results such as in the Stroop task in the people suffering from tinnitus as compared to normal subjects. Since Stroop engages the network overlapping the attention and tinnitus distress networks, it seems likely that Stroop exercises can effectively contribute to controlling the tinnitus and its consequent distress through improvement of the cognitive function and increasing the physiological inhibition.

Method

A total of 25 patients with chronic tinnitus (> 6 months) were randomly divided into two groups: an intervention group of 15 patients and a control group of 10 patients. Both groups were subjected to initial evaluations including pure tone audiometry, psychoacoustic measurements, tinnitus handicap inventory (THI) survey, and visual analogue scale (VAS) of annoyance and loudness. The intervention group underwent a rehabilitation program consisting of 6 Stroop training sessions. The control group didn't receive any training. Afterwards, both groups were reevaluated and the results were compared to those of initial evaluations.

Results

Results of this study indicated significant differences in THI scores and VAS of annoyance, before and after Stroop training in the intervention group, although no significant difference was observed when it came to VAS of loudness.

Conclusion

Successive sessions of conflict processing training can improve the annoyance of tinnitus by enhancing the patient's inhibition control, making this task a safe practice for tinnitus treatment.