Subjective hearing ability, physical and mental comorbidities in individuals with bothersome tinnitus in a Swedish population sample

Alexithymia in Patients with Somatization Difficulties and Tinnitus-Related Distress: A Systematic Review

Chronic tinnitus, the perception of sound without an external source, can significantly affect individuals' well-being. As an often medically unexplained symptom, chronic tinnitus can present as a "somatoform" or "functional" difficulty. Some evidence has pointed to alexithymia as a transdiagnostically relevant risk factor for both symptom clusters. Using a two-part rapid review-searching within EBSCO, Embase by Ovid, PubMed, Web of Science-we summarize psychological studies regarding alexithymia, i.e., difficulties in recognizing and expressing emotions and (1) somatoform conditions and (2) chronic tinnitus. For the former (inclusion criteria: (1) adult human beings with different kinds of somatization, (2) longitudinal study designs, (3) publication between 2001 and 2021, (4) full-text in English or German) we identified eight studies that revealed significant links between alexithymia and somatoform conditions. Psychotherapy improved alexithymia in most studies. Additionally, alexithymia was associated with broader treatment outcomes such as improvements in pain intensity, gastrointestinal symptoms, and patient-therapist alliance. The 'Risk Of Bias In Non-randomized Studies-of Interventions' tool (ROBINS-I) and 'Revised Cochrane risk-of-bias tool for randomized trials' (RoB 2) were used for risk of bias assessment. Summarizing all available studies on alexithymia and chronic tinnitus, we identified three studies. Inclusion criteria were: (1) adult human beings with chronic tinnitus, (2) publication between 2001 and 2021, (3) full-text in English or German. Risk of bias was assessed by the 'JBI Critical Appraisal Checklist for Analytical Cross Sectional Studies'. The available studies suggested a high rate of alexithymia (65.7%) in patients with chronic tinnitus. Tinnitus-related distress was significantly associated with alexithymia in two studies, one of which, however, found no differences in alexithymia between patients with bothersome versus non-bothersome tinnitus. Conversely, one study reported high levels of alexithymia in patients with low levels of tinnitus-related distress. Overall, alexithymia may be a transdiagnostic psychological indicator of somatization phenomena, which might include some chronic tinnitus presentations. Psychotherapy likely improves alexithymia as well as somatoform symptom presentations.

Influence of tinnitus, lifetime noise exposure, and firearm use on hearing thresholds, distortion product otoacoustic emissions, and their relative metric

Distortion product otoacoustic emissions (DPOAEs) and hearing thresholds (HTs) are widely used to evaluate auditory physiology. DPOAEs are sensitive to cochlear amplification processes, while HTs are additionally dependent upon inner hair cells, synaptic junctions, and the auditory nervous system. These distinctions between DPOAEs and HTs might help differentially diagnose auditory dysfunctions. This study aims to differentially diagnose auditory dysfunctions underlying tinnitus, firearm use, and high lifetime noise exposure (LNE) using HTs, DPOAEs, and a derived metric comparing HTs and DPOAEs, in a sample containing overlapping subgroups of 133 normal-hearing young adults (56 with chronic tinnitus). A structured interview was used to evaluate LNE and firearm use. Linear regression was used to model the relationship between HTs and DPOAEs, and their regression residuals were used to quantify their relative agreement. Participants with chronic tinnitus showed significantly elevated HTs, yet DPOAEs remained comparable to those without tinnitus. In contrast, firearm users revealed elevated HTs and significantly lower DPOAEs than predicted from HTs. High LNE was associated with elevated HTs and a proportional decline in DPOAEs, as predicted from HTs. We present a theoretical model to interpret the findings, which suggest neural (or synaptic) dysfunction underlying tinnitus and disproportional mechanical dysfunction underlying firearm use.

Limited Link of Common Blood Parameters with Tinnitus

Background: Tinnitus severity is generally assessed by psychometric and audiological instruments. However, no objective measure exists to evaluate the subjective discomfort and suffering caused by this hearing phenomenon. The objective of this work was to determine the possible blood parameters for diagnostics and therapy. Methods: We measured tinnitus distress by using the Tinnitus Questionnaire (TQ) and collected tinnitus-related audiological measures, namely the hearing threshold (HT), tinnitus loudness (TL), and sensation level (SL, i.e., the tinnitus loudness/hearing threshold at a tinnitus frequency). Blood samples were taken from 200 outpatients of the Tinnitus Centre of the Charité, and 46 routine blood count parameters were examined. The possible interactions were determined by (robust) linear models. Results: Tinnitus distress and audiological measurements were largely uncorrelated but could partly be predicted by selected blood parameters. First, the erythrocyte counts predicted tinnitus distress to a small extent. Second, the levels of vitamin D3 explained about 6% of tinnitus loudness and, age-dependently, the hearing threshold variability. Last, the levels of uric acid explained about 5% of the sensation level variability. Conclusions: Tinnitus is a multidimensional phenomenon. The marginal influences of blood markers suggest the possible roles of inflammation and oxidative stress produced by psychological or somatic burdens. Clinically, a vitamin D substitution (in older patients) might have a hearing-protective effect.

Third-Party Disability for Significant Others of Individuals with Tinnitus: A Cross-Sectional Survey Design

There is currently increasing awareness of third-party disability, defined as the disability and functioning of a significant other (SO) due to a health condition of one of their family members. The effects of third-party disability on the SOs of individuals with tinnitus has received little attention. To address this knowledge gap, this study investigated third-party disability in the significant others (SOs) of individuals with tinnitus. A cross-sectional survey design included 194 pairs of individuals from the USA with tinnitus and their significant others. The SO sample completed the Consequences of Tinnitus on Significant Others Questionnaire (CTSOQ). Individuals with tinnitus completed standardized self-reported outcome measures for tinnitus severity, anxiety, depression, insomnia, hearing-related quality of life, tinnitus cognitions, hearing disability, and hyperacusis. The CTSOQ showed that 34 (18%) of the SOs were mildly impacted, 59 (30%) were significantly impacted, and 101 (52%) were severely impact. The clinical variables of tinnitus severity, anxiety, and hyperacusis in individuals with tinnitus were the best predictors of the impact of tinnitus on SOs. These results show that the SOs of individuals with tinnitus may experience third-party disability. The effect of the individual's tinnitus on their SO may be greater when the individual with tinnitus has a higher level of tinnitus severity, anxiety, and hyperacusis.

Do you Hear what I Hear? A Qualitative Study Examining Psychological Associations Underlying Evaluations of Everyday Sounds in Patients with Chronic Tinnitus

Tinnitus is a multifactorial phenomenon and psychological, audiological, or medical factors can facilitate its onset or maintenance. A growing body of research investigates individuals' perceptions, associations, and experiences of living with tinnitus. This body of research examines tinnitus as a condition rather than a symptom. We examine a sample of chronic tinnitus patients in terms of associations that are induced by neutral sounds. In particular, we investigate how patients with chronic tinnitus ascribe meaning to those neutral sounds. The present study uses Mayring's content analysis to explore the content of psychological associations underlying valence ratings of everyday neutral sounds. Nine tinnitus patients completed a hearing exercise, during which they listened to seven neutral sounds, following which we examined their sound-induced associations using semi-structured interviews. Three groups of factors influenced patients' associations and valence ratings of neutral sounds: affect, episodic memory, and 'other'. The former two factors further comprised two subcategories. In line with previous psychoaudiological research designs, our findings suggest that neutral, everyday auditory stimuli evoke strong affective reactions-possibly through serving as retrieval cues for episodic memories. Based on these findings, we discuss our results in the context of previous psychoaudiological findings and propose further research concerning psychological associations that may specifically underlie the tinnitus sound.

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.

A genome-wide association study of tinnitus reveals shared genetic links to neuropsychiatric disorders

Tinnitus, a phantom perception of sound in the absence of any external sound source, is a prevalent health condition often accompanied by psychiatric comorbidities. Recent genome-wide association studies (GWAS) highlighted a polygenic nature of tinnitus susceptibility. A shared genetic component between tinnitus and psychiatric conditions remains elusive. Here we present a GWAS using the UK Biobank to investigate the genetic processes linked to tinnitus and tinnitus-related distress, followed by gene-set enrichment analyses. The UK Biobank sample comprised 132,438 individuals with tinnitus and genotype data. Among the study sample, 38,525 individuals reported tinnitus, and 26,889 participants mentioned they experienced tinnitus-related distress in daily living. The genome-wide association analyses were conducted on tinnitus and tinnitus-related distress. We conducted enrichment analyses using FUMA to further understand the genetic processes linked to tinnitus and tinnitus-related distress. A genome-wide significant locus (lead SNP: rs71595470) for tinnitus was obtained in the vicinity of GPM6A. Nineteen independent loci reached suggestive association with tinnitus. Fifteen independent loci reached suggestive association with tinnitus-related distress. The enrichment analysis revealed a shared genetic component between tinnitus and psychiatric traits, such as bipolar disorder, feeling worried, cognitive ability, fast beta electroencephalogram, and sensation seeking. Metabolic, cardiovascular, hematological, and pharmacological gene sets revealed a significant association with tinnitus. Anxiety and stress-related gene sets revealed a significant association with tinnitus-related distress. The GWAS signals for tinnitus were enriched in the hippocampus and cortex, and for tinnitus-related distress were enriched in the brain and spinal cord. This study provides novel insights into genetic processes associated with tinnitus and tinnitus-related distress and demonstrates a shared genetic component underlying tinnitus and psychiatric conditions. Further collaborative attempts are necessary to identify genetic components underlying the phenotypic heterogeneity in tinnitus and provide biological insight into the etiology.

Associations between Demographics, Tinnitus Specific-, Audiological-, General- and Mental Health Factors, and the Impact of Tinnitus on Daily Life

Our objective was to study associations between demographics, tinnitus specific-, audiological-, general- and mental health characteristics, and impact of tinnitus in the general population. In this cross-sectional survey study in the Dutch population, data were prospectively gathered. Tinnitus impact was assessed with the Tinnitus Functional Index (TFI). We included participants who experienced tinnitus and for whom a total TFI score could be calculated (n = 212). We performed univariable and multivariable regression analyses. Due to logarithmical transformation, the B-scores were back-transformed to show the actual difference in points on the TFI. People who considered hyperacusis a small problem had a 12.5-point higher TFI score, those who considered it a mediocre problem had a 17.6-point higher TFI score and those who considered it a large problem had a 24.1-point higher TFI score compared to people who did not consider hyperacusis a problem. People who indicated having minor hearing problems had a 10.5-point higher TFI score, those with mediocre hearing problems had a 20.4-point higher TFI score and those with severe hearing problems had a 41.6-point higher TFI score compared to people who did not have subjective hearing problems. In conclusion, audiological risk factors, such as hearing problems and hyperacusis, have the largest association with the impact of tinnitus on daily life, compared to other assessed variables. The results of this study can be used in future research to find targeted interventions to diminish the impact of tinnitus.

Hearing loss and depressive symptoms in older Chinese: whether social isolation plays a role

Background

Existing evidence links hearing loss to depressive symptoms, with the extent of association and underlying mechanisms remaining inconclusive. We conducted a cross-sectional study to examine the association of hearing loss with depressive symptoms and explored whether social isolation mediated the association.

Methods

Eight thousand nine hundred sixty-two participants from Guangzhou Biobank Cohort Study were included. Data on self-reported hearing status, the 15-item Geriatric Depression Scale (GDS-15), social isolation and potential confounders were collected by face-to-face interview.

Results

The mean (standard deviation) age of participants was 60.2 (7.8) years. The prevalence of poor and fair hearing was 6.8% and 60.8%, respectively. After adjusting for age, sex, household income, education, occupation, smoking, alcohol use, self-rated health, comorbidities, compared with participants who had normal hearing, those with poor hearing (β = 0.74, 95% confidence interval (CI) 0.54, 0.94) and fair hearing (β = 0.59, 95% CI 0.48, 0.69) had higher scores of GDS-15. After similar adjustment, those with poor hearing (odds ratio (OR) = 2.13, 95% CI 1.65, 2.74) or fair hearing (OR = 1.68, 95% CI 1.43, 1.99) also showed higher odds of depressive symptoms. The association of poor and fair hearing with depressive symptoms attenuated slightly but not substantially after additionally adjusting for social isolation. In the mediation analysis, the adjusted proportion of the association mediated through social isolation was 9% (95% CI: 6%, 22%).

Conclusion

Poor hearing was associated with a higher risk of depressive symptoms, which was only partly mediated by social isolation. Further investigation of the underlying mechanisms is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03311-0.

Sex Differences in Comorbidity Combinations in the Swedish Population

High comorbidity rates, especially mental–physical comorbidity, constitute an increasing health care burden, with women and men being differentially affected. To gain an overview of comorbidity rates stratified by sex across a range of different conditions, this study examines comorbidity patterns within and between cardiovascular, pulmonary, skin, endocrine, digestive, urogenital, musculoskeletal, neurological diseases, and psychiatric conditions. Self-report data from the LifeGene cohort of 31,825 participants from the general Swedish population (62.5% female, 18–84 years) were analyzed. Pairwise comorbidity rates of 54 self-reported conditions in women and men and adjusted odds ratios (ORs) for their comparison were calculated. Overall, the rate of pairwise disease combinations with significant comorbidity was higher in women than men (14.36% vs. 9.40%). Among psychiatric conditions, this rate was considerably high, with 41.76% in women and 39.01% in men. The highest percentages of elevated mental–physical comorbidity in women were found for musculoskeletal diseases (21.43%), digestive diseases (20.71%), and skin diseases (13.39%); in men, for musculoskeletal diseases (14.29%), neurological diseases (11.22%), and digestive diseases (10%). Implications include the need for integrating mental and physical health care services and a shift from a disease-centered to an individualized, patient-centered focus in clinical care.

Higher Peripheral Inflammation Is Associated With Lower Orbitofrontal Gamma Power in Chronic Tinnitus

Chronic tinnitus, the continuous perception of a phantom sound, is a highly prevalent audiological symptom, for which the underlying pathology has not yet been fully understood. It is associated with neurophysiological alterations in the central nervous system and chronic stress, which can be related with a disinhibition of the inflammatory system. We here investigated the association between resting-state oscillatory activity assessed with Magnetoencephalography (MEG), and peripheral inflammation assessed by C-reactive protein (CRP) in a group of patients with chronic tinnitus (N = 21, nine males, mean age: 40.6 ± 14.6 years). Additionally, CRP was assessed in an age- and sex-matched healthy control group (N = 21, nine males, mean age: 40.9 ± 15.2 years). No MEG data was available for the control group. We found a significant negative correlation between CRP and gamma power in the orbitofrontal cortex in tinnitus patients (p < 0.001), pointing to a deactivation of the orbitofrontal cortex when CRP was high. No significant clusters were found for other frequency bands. Moreover, CRP levels were significantly higher in the tinnitus group than in the healthy controls (p = 0.045). Our results can be interpreted based on findings from previous studies having disclosed the orbitofrontal cortex as part of the tinnitus distress network. We suggest that higher CRP levels and the associated deactivation of the orbitofrontal cortex in chronic tinnitus patients is maintaining the tinnitus percept through disinhibition of the auditory cortex and attentional or emotional top-down processes. Although the direction of the association (i.e., causation) between CRP levels and orbitofrontal gamma power in chronic tinnitus is not yet known, inflammation reducing interventions are promising candidates when developing treatments for tinnitus patients. Overall, our study highlights the importance of considering immune-brain communication in tinnitus research.

Development and psychometric validation of a questionnaire assessing the impact of tinnitus on significant others

INTRODUCTION

Despite evidence showing that tinnitus can have a detrimental impact on significant others (SOs), no standardized self-reported measure is currently available that specifically assesses the presence of third-party disability for tinnitus. The aim of this study was to develop and assess the psychometric properties of a newly developed self-reported measure for SOs of tinnitus and assess how scores could be meaningfully interpreted.

METHODS

The research consisted of two phases. During Phase I, the Consequences of Tinnitus on Significant Others Questionnaire (CTSOQ) was developed using the The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidance. Phase II included the assessment of psychometric properties of the CTSOQ including the construct validity, internal consistency, interpretability, and responsiveness. Pairs of 194 individuals with tinnitus and their SOs completed a series of online questionnaires. SOs completed the CTSOQ measure while individuals with tinnitus completed measures related to tinnitus distress, anxiety, depression, insomnia, and quality of life.

RESULTS

A 25 item CTSOQ was developed using a formative model. The questionnaire validation process indicated good psychometric properties with an internal consistency of 0.93 and inter-item correlation of 0.60. Support was found for the construct and discriminative validity of the measure. Floor and ceiling effects were negligible. Scores can be meaningfully interpreted to indicate mild, significant, or severe effect of tinnitus on SOs. The questionnaire was also found to be responsive to treatment-related changes.

CONCLUSIONS

The CTSOQ was found to have sufficient measurement properties suggesting that it is a suitable measure of third-party disability for SOs of individuals with tinnitus. Further research should be initiated to measure face validity and what scores reflect clinically meaningful change.