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Langguth B, Kleinjung T, Schlee W, Vanneste S, De Ridder D. Tinnitus Guidelines and Their Evidence Base. J Clin Med 2023; 12:jcm12093087. [PMID: 37176527 PMCID: PMC10178961 DOI: 10.3390/jcm12093087] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/17/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023] Open
Abstract
Evidence-based medicine (EBM) is generally accepted as the gold standard for high-quality medicine and, thus, for managing patients with tinnitus. EBM integrates the best available scientific information with clinical experience and patient values to guide decision-making about clinical management. To help health care providers and clinicians, the available evidence is commonly translated into medical or clinical guidelines based on a consensus. These involve a systematic review of the literature and meta-analytic aggregation of research findings followed by the formulation of clinical recommendations. However, this approach also has limitations, which include a lack of consideration of individual patient characteristics, the susceptibility of guideline recommendations to material and immaterial conflicts of interest of guideline authors and long latencies till new knowledge is implemented in guidelines. A further important aspect in interpreting the existing literature is that the absence of evidence is not evidence of absence. These circumstances could result in the decoupling of recommendations and their supporting evidence, which becomes evident when guidelines from different countries differ in their recommendations. This opinion paper will discuss how these weaknesses can be addressed in tinnitus.
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Affiliation(s)
- Berthold Langguth
- Department of Psychiatry and Psychotherapy, University of Regensburg, 93053 Regensburg, Germany
- Interdisciplinary Tinnitus Clinic, University of Regensburg, 93053 Regensburg, Germany
| | - Tobias Kleinjung
- Department of Otorhinolaryngology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Winfried Schlee
- Department of Psychiatry and Psychotherapy, University of Regensburg, 93053 Regensburg, Germany
- Interdisciplinary Tinnitus Clinic, University of Regensburg, 93053 Regensburg, Germany
- Institute for Information and Process Management, Eastern Switzerland University of Applied Sciences, 9001 St. Gallen, Switzerland
| | - Sven Vanneste
- Trinity Institute for Neuroscience, Trinity College Dublin, D02 PN40 Dublin, Ireland
- Global Brain Health Institute, Trinity College Dublin, D02 PN40 Dublin, Ireland
- School of Psychology, Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Dirk De Ridder
- Section of Neurosurgery, Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin 9016, New Zealand
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Kim SH, Kim D, Lee JM, Lee SK, Kang HJ, Yeo SG. Review of Pharmacotherapy for Tinnitus. Healthcare (Basel) 2021; 9:healthcare9060779. [PMID: 34205776 PMCID: PMC8235102 DOI: 10.3390/healthcare9060779] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 11/16/2022] Open
Abstract
Various medications are currently used in the treatment of tinnitus, including anesthetics, antiarrhythmics, anticonvulsants, antidepressants, antihistamines, antipsychotics, anxiolytics, calcium channel blockers, cholinergic antagonists, NMDA antagonists, muscle relaxants, vasodilators, and vitamins. To date, however, no medications have been specifically approved to treat tinnitus by the US Food and Drug Administration (FDA). In addition, medicines used to treat other diseases, as well as foods and other ingested materials, can result in unwanted tinnitus. These include alcohol, antineoplastic chemotherapeutic agents and heavy metals, antimetabolites, antitumor agents, antibiotics, caffeine, cocaine, marijuana, nonnarcotic analgesics and antipyretics, ototoxic antibiotics and diuretics, oral contraceptives, quinine and chloroquine, and salicylates. This review, therefore, describes the medications currently used to treat tinnitus, including their mechanisms of action, therapeutic effects, dosages, and side-effects. In addition, this review describes the medications, foods, and other ingested agents that can induce unwanted tinnitus, as well as their mechanisms of action.
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Affiliation(s)
- Sang Hoon Kim
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02447, Korea; (S.H.K.); (J.-M.L.); (S.K.L.); (H.J.K.)
| | - Dokyoung Kim
- Department of Anatomy and Neurobiology, College of Medicine, Kyung Hee University, Seoul 02447, Korea;
| | - Jae-Min Lee
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02447, Korea; (S.H.K.); (J.-M.L.); (S.K.L.); (H.J.K.)
| | - Sun Kyu Lee
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02447, Korea; (S.H.K.); (J.-M.L.); (S.K.L.); (H.J.K.)
| | - Hee Jin Kang
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02447, Korea; (S.H.K.); (J.-M.L.); (S.K.L.); (H.J.K.)
| | - Seung Geun Yeo
- Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02447, Korea; (S.H.K.); (J.-M.L.); (S.K.L.); (H.J.K.)
- Correspondence: ; Tel.: +82-2-958-8980; Fax: +82-2-958-8470
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Farhadi M, Salem MM, Asghari A, Daneshi A, Mirsalehi M, Mahmoudian S. Impact of Acamprosate on Chronic Tinnitus: A Randomized-Controlled Trial. Ann Otol Rhinol Laryngol 2020; 129:1110-1119. [PMID: 32500717 DOI: 10.1177/0003489420930773] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES Tinnitus is a common and distressing otologic symptom, with various probable pathophysiologic mechanisms, such as an imbalance between excitatory and inhibitory mechanisms. Acamprosate, generally used to treat alcoholism, is a glutaminergic antagonist and GABA agonist suggested for treating tinnitus. Thus, we aimed to evaluate the efficacy and safety of acamprosate in the treatment of tinnitus. METHODS The current randomized-controlled trial study included 20 subjects with chronic tinnitus. After performing psycho-acoustic, psychometric and electrophysiological evaluations, all studied tinnitus subjects were randomly divided into two groups of acamprosate and placebo. The first group received oral acamprosate (two tablets of 333 mg/d, three times a day), whereas the second group was given placebo treatment (two tablets, three times a day). After the first 30 days, all evaluations were repeated for the studied groups just in the same manner before the study. Subsequently, the final results of each evaluation were compared together with the baseline values. RESULTS Nine studied subjects randomly received acamprosate, whereas eleven others received a placebo. There was no significant improvement in the psycho-acoustic tests, except a decrease was observed in the pitch match of tinnitus (P = .039). For those subjects who were receiving acamprosate, a significant reduction was observed in tinnitus handicap inventory (P = .006), tinnitus questionnaire scores (P = .007), and the visual analog scores (P = .007) compared to the placebo group. There was a significant reduction in Action Potential latency (P = .048) as well as an increase in the amplitude of distortion product otoacoustic emissions at 4 kHz (P = .048). CONCLUSIONS The study results indicated a subjective relief of tinnitus as well as some degree of the electrophysiological improvement at the level of the cochlear and the distal portion of the auditory nerve among the subjects who received the acamprosate. CLINICAL TRIAL REGISTRATION CODE IRCT2013121115751N1.
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Affiliation(s)
- Mohammad Farhadi
- ENT and Head & Neck Research Center and Department, the Five Senses Health Institute, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Mahdi Salem
- ENT and Head & Neck Research Center and Department, the Five Senses Health Institute, Iran University of Medical Sciences, Tehran, Iran
| | - Alimohamad Asghari
- Skull Base Research Center, Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Ahmad Daneshi
- ENT and Head & Neck Research Center and Department, the Five Senses Health Institute, Iran University of Medical Sciences, Tehran, Iran
| | - Marjan Mirsalehi
- ENT and Head & Neck Research Center and Department, the Five Senses Health Institute, Iran University of Medical Sciences, Tehran, Iran
| | - Saeid Mahmoudian
- ENT and Head & Neck Research Center and Department, the Five Senses Health Institute, Iran University of Medical Sciences, Tehran, Iran
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Abstract
Tinnitus is a common symptom for which there is in most cases no causal therapy. The search for an improvement of tinnitus through pharmacological interventions has a long tradition. The observation that tinnitus can be transiently suppressed by the use of lidocaine has shown that the symptom is susceptible to pharmacotherapy. So far, however, no medication has been found for either acute or chronic subjective tinnitus that reliably leads to a long-term reduction or even complete disappearance of the symptom for the majority of tinnitus sufferers. Nevertheless, in everyday clinical life, drugs are frequently used, usually off-label, to relieve tinnitus or tinnitus-associated symptoms (e.g. sleep disturbance, depression, anxiety disorder or hearing loss). This chapter shows the different approaches to acute and chronic subjective tinnitus by means of pharmacotherapeutic interventions. Furthermore, this review reports on the scientific studies carried out in this area in recent years and explains the difficulties in finding a suitable medication for most forms of tinnitus. In addition, it reports on the pharmacotherapeutic options for objective tinnitus and describes the development of tinnitus as a side effect of certain drugs. Finally, possible target structures are mentioned, which should possibly be addressed in pharmacological studies in the near future.
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Affiliation(s)
- Tobias Kleinjung
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
| | - Berthold Langguth
- Department of Psychiatry and Psychotherapy, Interdisciplinary Tinnitus Center, University of Regensburg, Regensburg, Germany
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Sheppard A, Stocking C, Ralli M, Salvi R. A review of auditory gain, low-level noise and sound therapy for tinnitus and hyperacusis. Int J Audiol 2019; 59:5-15. [DOI: 10.1080/14992027.2019.1660812] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Adam Sheppard
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
| | - Christina Stocking
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
| | - Massimo Ralli
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, Rome, Italy
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
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Langguth B, Elgoyhen AB, Cederroth CR. Therapeutic Approaches to the Treatment of Tinnitus. Annu Rev Pharmacol Toxicol 2019; 59:291-313. [DOI: 10.1146/annurev-pharmtox-010818-021556] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tinnitus is a highly prevalent condition that is associated with hearing loss in most cases. In the absence of external stimuli, phantom perceptions of sounds emerge from alterations in neuronal activity within central auditory and nonauditory structures. Pioneering studies using lidocaine revealed that tinnitus is susceptible to pharmacological interventions. However, lidocaine is not effective in all patients, and no other drug has been identified with clear efficacy for the long-term treatment of tinnitus. In this review, we present recent advances in tinnitus research, including more detailed knowledge of its pathophysiology and involved neurotransmitter systems. Moreover, we summarize results from animal and clinical treatment studies as well as from studies that identified tinnitus as a side effect of pharmacological treatments. Finally, we focus on challenges in the development of pharmacological compounds for the treatment of tinnitus, namely the limitations of available animal models and of standardized clinical research methodologies.
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Affiliation(s)
- Berthold Langguth
- Department of Psychiatry and Psychotherapy, and Interdisciplinary Tinnitus Clinic, University of Regensburg, 93053 Regensburg, Germany
| | - Ana Belen Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres,” Consejo Nacional de Investigaciones Científicas y Técnicas, 1428 Buenos Aires, Argentina
- Instituto de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, 1121 Buenos Aires, Argentina
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Zenner HP, Delb W, Kröner-Herwig B, Jäger B, Peroz I, Hesse G, Mazurek B, Goebel G, Gerloff C, Trollmann R, Biesinger E, Seidler H, Langguth B. A multidisciplinary systematic review of the treatment for chronic idiopathic tinnitus. Eur Arch Otorhinolaryngol 2016; 274:2079-2091. [DOI: 10.1007/s00405-016-4401-y] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 11/19/2016] [Indexed: 01/17/2023]
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Imsuwansri T, Hoare DJ, Phaisaltuntiwongs W, Srisubat A, Snidvongs K. Glutamate receptor antagonists for tinnitus. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2016. [DOI: 10.1002/14651858.cd012391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Thanarath Imsuwansri
- Ministry of Public Health; Institute of Medical Research and Technology Assessment, Dept of Medical Services; Tiwanon Nonthaburi Thailand 11000
| | - Derek J Hoare
- Division of Clinical Neuroscience, School of Medicine, University of Nottingham; NIHR Nottingham Hearing Biomedical Research Unit; Ropewalk House, 113 The Ropewalk Nottingham UK NG1 5DU
| | - Wanasri Phaisaltuntiwongs
- Sirindhorn Hospital, Medical Service Department; Otorhinolaryngology Section; Bangkok Metropolitan Administration Onnut Road, Prawet District Bangkok Thailand 10250
| | - Attasit Srisubat
- Ministry of Public Health; Institute of Medical Research and Technology Assessment, Dept of Medical Services; Tiwanon Nonthaburi Thailand 11000
| | - Kornkiat Snidvongs
- Chulalongkorn University; Department of Otolaryngology, Faculty of Medicine; Bangkok Thailand
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Beebe Palumbo D, Joos K, De Ridder D, Vanneste S. The Management and Outcomes of Pharmacological Treatments for Tinnitus. Curr Neuropharmacol 2016; 13:692-700. [PMID: 26467416 PMCID: PMC4761638 DOI: 10.2174/1570159x13666150415002743] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/12/2015] [Accepted: 04/09/2015] [Indexed: 01/28/2023] Open
Abstract
Tinnitus, a phantom sensation experienced by people around the world, currently is endured
without a known cure. Some find the condition tolerable, while others are tortured on a daily basis
from the incessant phantom noises. For those who seek treatment, oftentimes, they have a comorbid
condition (e.g., depression, anxiety, insomnia), which is treated pharmaceutically. These products aim
to reduce the comorbities associated with tinnitus thereby minimizing the overall burden present.
Because of the phantom nature of tinnitus, it is often compared to neurologic pain. Since pain can be managed with
pharmaceutical options, it is reasonable to assume that similar agents might work to alleviate tinnitus. The effects of
antidepressants, benzodiazepines, anticonvulsants, and glutamate antagonists are reviewed in this paper. Table 1 summarizes
the pharmaceutical products discussed. Due to the variety of comorbid factors and potential causes of tinnitus, there may
not be one pharmaceutical treatment that will combat every type of tinnitus. Nevertheless, a product that finally addresses
the true cause of tinnitus, and not just its comorbidities, will benefit millions of people worldwide.
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Affiliation(s)
| | | | | | - Sven Vanneste
- Lab for Auditory & Integrative Neuroscience, School of Behavioral & Brain Science, University of Texas at Dallas, W 1966 Inwood Rd, Dallas, Texas 75235, USA
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Langguth B, Elgoyhen AB. Current pharmacological treatments for tinnitus. Expert Opin Pharmacother 2012; 13:2495-509. [DOI: 10.1517/14656566.2012.739608] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wallhäusser-Franke E, Schredl M, Delb W. Tinnitus and insomnia: is hyperarousal the common denominator? Sleep Med Rev 2012; 17:65-74. [PMID: 22750224 DOI: 10.1016/j.smrv.2012.04.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 04/12/2012] [Accepted: 04/13/2012] [Indexed: 10/28/2022]
Abstract
Tinnitus is an auditory sensation that is generated by aberrant activation within the auditory system. Sleep disturbances are a frequent problem in the tinnitus population. They are known to worsen the distress caused by the tinnitus which in turn worsens sleep quality. Beyond that, disturbed sleep is a risk factor for mental health problems and distressing tinnitus is often associated with enhanced depressivity, anxiety, and somatic symptom severity. Moreover there is evidence that therapies which alleviate tinnitus-related distress have a positive influence on sleep quality and help interrupt this vicious cycle. This suggests that distressing tinnitus and insomnia may both be promoted by similar physiological mechanisms. One candidate mechanism is hyperarousal caused by enhanced activation of the sympathetic nervous system. There is increasing evidence for hyperarousal in insomnia patients, and animal models of tinnitus and insomnia show conspicuous similarities in the activation pattern of limbic and autonomous brain regions. In this article we review the evidence for this hypothesis which may have implications for therapeutic intervention in tinnitus patients with comorbid insomnia.
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Affiliation(s)
- Elisabeth Wallhäusser-Franke
- Medical Faculty Mannheim, Heidelberg University, Department of Phoniatrics and Audiology, Tridomus House C, Ludolf-Krehl-Str. 13-17, 68167 Mannheim, Germany.
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Elgoyhen AB, Langguth B, Vanneste S, De Ridder D. Tinnitus: network pathophysiology-network pharmacology. Front Syst Neurosci 2012; 6:1. [PMID: 22291622 PMCID: PMC3265967 DOI: 10.3389/fnsys.2012.00001] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Accepted: 01/11/2012] [Indexed: 01/12/2023] Open
Abstract
Tinnitus, the phantom perception of sound, is a prevalent disorder. One in 10 adults has clinically significant subjective tinnitus, and for one in 100, tinnitus severely affects their quality of life. Despite the significant unmet clinical need for a safe and effective drug targeting tinnitus relief, there is currently not a single Food and Drug Administration (FDA)-approved drug on the market. The search for drugs that target tinnitus is hampered by the lack of a deep knowledge of the underlying neural substrates of this pathology. Recent studies are increasingly demonstrating that, as described for other central nervous system (CNS) disorders, tinnitus is a pathology of brain networks. The application of graph theoretical analysis to brain networks has recently provided new information concerning their topology, their robustness and their vulnerability to attacks. Moreover, the philosophy behind drug design and pharmacotherapy in CNS pathologies is changing from that of "magic bullets" that target individual chemoreceptors or "disease-causing genes" into that of "magic shotguns," "promiscuous" or "dirty drugs" that target "disease-causing networks," also known as network pharmacology. In the present work we provide some insight into how this knowledge could be applied to tinnitus pathophysiology and pharmacotherapy.
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Affiliation(s)
- Ana B. Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Consejo Nacional de Investigaciones Científicas y Técnicas and Tercera Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos AiresBuenos Aires, Argentina
| | - Berthold Langguth
- Interdisciplinary Tinnitus Clinic, Departments of Psychiatry and Psychotherapy, University of RegensburgRegensburg, Germany
| | - Sven Vanneste
- TRI, BRAIN and Department of Neurosurgery, University Hospital AntwerpEdegem, Belgium
| | - Dirk De Ridder
- TRI, BRAIN and Department of Neurosurgery, University Hospital AntwerpEdegem, Belgium
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Abstract
OBJECTIVES Depressive symptoms are common in individuals with tinnitus and may substantially aggravate their distress. The mechanisms, however, by which depression and tinnitus mutually interact are still not fully understood. METHODS Here we review neurobiological knowledge relevant for the interplay between depression and tinnitus. RESULTS Neuroimaging studies confirm the existence of neural circuits that are activated both in depression and tinnitus. Studies of neuroendocrine function demonstrate alterations of the HPA-axis in depression and, more recently, in tinnitus. Studies addressing neurotransmission suggest that the dorsal cochlear nucleus that is typically hyperactive in tinnitus, is also involved in the control of attention and emotional responses via projections to the locus coeruleus, the reticular formation and the raphe nuclei. Impaired hippocampal neurogenesis has been documented in animals with tinnitus after noise trauma, as in animal models of depression. Finally, from investigations of human candidate genes, there is some evidence to suggest that variant BDNF may act as a common susceptibility factor in both disorders. CONCLUSIONS These parallels in the pathophysiology of tinnitus and depression argue against comorbidity by chance and against depression as pure reaction on tinnitus. Instead, they stand for a complex interplay between tinnitus and depression. Implications for tinnitus treatment are discussed.
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Affiliation(s)
- Berthold Langguth
- Department of Psychiatry and Psychotherapy, University of Regensburg, Regensburg, Germany.
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Evaluation of a Customized Acoustical Stimulus System in the Treatment of Chronic Tinnitus. Otol Neurotol 2011; 32:710-6. [DOI: 10.1097/mao.0b013e318217d459] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Tinnitus, the perception of sound in the absence of an auditory stimulus, is perceived by about 1 in 10 adults, and for at least 1 in 100, tinnitus severely affects their quality of life. Because tinnitus is frequently associated with irritability, agitation, stress, insomnia, anxiety and depression, the social and economic burdens of tinnitus can be enormous. No curative treatments are available. However, tinnitus symptoms can be alleviated to some extent. The most widespread management therapies consist of auditory stimulation and cognitive behavioral treatment, aiming at improving habituation and coping strategies. Available clinical trials vary in methodological rigor and have been performed for a considerable number of different drugs. None of the investigated drugs have demonstrated providing replicable long-term reduction of tinnitus impact in the majority of patients in excess of placebo effects. Accordingly, there are no FDA or European Medicines Agency approved drugs for the treatment of tinnitus. However, in spite of the lack of evidence, a large variety of different compounds are prescribed off-label. Therefore, more effective pharmacotherapies for this huge and still growing market are desperately needed and even a drug that produces only a small but significant effect would have an enormous therapeutic impact. This review describes current and emerging pharmacotherapies with current difficulties and limitations. In addition, it provides an estimate of the tinnitus market. Finally, it describes recent advances in the tinnitus field which may help overcome obstacles faced in the pharmacological treatment of tinnitus. These include incomplete knowledge of tinnitus pathophysiology, lack of well-established animal models, heterogeneity of different forms of tinnitus, difficulties in tinnitus assessment and outcome measurement and variability in clinical trial methodology.
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Affiliation(s)
- Berthold Langguth
- University of Regensburg, Interdisciplinary Tinnitus Clinic, Department of Psychiatry and Psychotherapy, Universitaetsstrabetae 84, 93053 Regensburg, Germany.
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Abstract
Subjective tinnitus, the phantom ringing or buzzing sensation that occurs in the absence of sound, affects 12-14% of adults; in some cases the tinnitus is so severe or disabling that patients seek medical treatment. However, although the economic and emotional impact of tinnitus is large, there are currently no FDA-approved drugs to treat this condition. Clinical trials are now underway to evaluate the efficacy of N-methyl-d-aspartate (NMDA) and dopamine D(2) antagonists, selective serotonin reuptake inhibitors (SSRIs), γ-aminobutyric acid (GABA) agonists and zinc dietary supplements. Previous off-label clinical studies, while not definitive, suggest that patients with severe depression may experience improvement in their tinnitus after treatment with antidepressants such as nortriptyline or sertraline. A small subpopulation of patients with what has been described as "typewriter tinnitus" have been shown to gain significant relief from the anticonvulsant carbamazepine. Preliminary studies with misoprostol, a synthetic prostaglandin E1 analogue, and sulpiride, a dopamine D(2) antagonist, have shown promise. Animal behavioral studies suggest that GABA transaminase inhibitors and potassium channel modulators can suppress tinnitus. Additionally, improvements in tinnitus have also been noted in patients taking melatonin for significant sleep disturbances. Like other complex neurological disorders, one drug is unlikely to resolve tinnitus in all patients; therapies targeting specific subgroups are likely to yield the greatest success.
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Affiliation(s)
- R. Salvi
- Center for Hearing and Deafness and Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY 14214, USA
| | - E. Lobarinas
- Center for Hearing and Deafness and Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY 14214, USA
| | - W. Sun
- Center for Hearing and Deafness and Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY 14214, USA
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