Tinnitus and Stress : An Interdisciplinary Companion for Healthcare Professionals

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Preface 6 Acknowledgments 7 Contents 8 1: Introduction 9 1.1 Tinnitus and Tinnitus-Related Distress 12 References 14 2: Stress and Glucocorticoid Action in the Brain and Ear: Implications for Tinnitus 15 2.1 Introduction 15 2.2 The Concept Stress, Allostasis, and the Allostatic Load 16 2.3 Mediators of the Stress Response 18 2.4 Pulsatility of the HPA Axis 20 2.5 Access of Corticosteroids to Brain Targets 21 2.6 Corticosteroid Receptors 22 2.7 Behavioral and Neuroendocrine Feedback Action of Corticosteroids in the Brain 25 2.8 Role of MR and GR in Coping with Stress 28 2.9 MR:GR Balance: Genetics 29 2.10 MR/GR Balance: Phenotype 30 2.11 Implications for Tinnitus 31 2.12 Corticosteroids-Based Treatment Options 35 References 36 3: Stress-Related Psychological Disorders and Tinnitus 44 3.1 Introduction 44 3.2 Psychological Disorders 45 3.3 Affective Disorders 46 3.4 Anxiety Disorders 47 3.5 Type D Personality and Tinnitus 47 3.6 Population Studies Reporting Association Between Tinnitus and Stress 48 3.7 Does Tinnitus Cause Stress or Does Stress Cause Tinnitus? 50 3.8 Proposing Treatments: Enrolment Issues 54 3.9 Treatment of Comorbid Psychological Disorders in Patients with Tinnitus 54 References 55 4: Circadian Influences on the Auditory System 59 4.1 Introduction 59 4.2 Circadian Rhythms 59 4.2.1 What Are They 59 4.2.2 Organization of the Circadian System 60 4.3 Molecular Biology of Circadian Rhythms 61 4.3.1 Core Clock Genes 61 4.3.2 From Molecules to Physiology 64 4.3.2.1 The SCN and the Adrenal Glands: Teamwork for Body Synchrony? 66 4.3.2.2 Physiological Functions Controlled by Circadian Rhythms and Their Dysregulation 67 4.3.3 Auditory System and Circadian Rhythms 69 4.3.3.1 The Day-Night Susceptibility to Auditory Trauma 69 4.3.3.2 Involvement of Neurotrophic Signaling in the Differential Sensitivity to Noise Trauma Throughout the Day 70 4.3.3.3 Molecular Biology of Cochlear Circadian Rhythm 70 4.3.3.4 Circadian Rhythms in the Inferior Colliculus 73 4.3.3.5 Central Influence of Cochlear and IC Rhythms: Predictive Models 74 4.3.4 Auditory Pathologies and Disrupted Circadian Rhythms 75 4.3.4.1 Psychological Consequences of Disrupted Circadian Rhythms and the Potential Role in Tinnitus 76 4.4 Clinical Implications of Circadian Influences for Tinnitus Therapy 77 References 78 5: Animal Models of Stress and Tinnitus 83 5.1 Stress 83 5.2 Hypothalamic-Pituitary-Adrenal Axis and the Auditory System 84 5.3 Recognizing Stress in Animals 84 5.4 Causing Stress in Animals 86 5.4.1 Restraint Stress 86 5.4.2 Electric Foot Shock-Induced Stress 86 5.4.3 Noise-Induced Stress 87 5.5 Stress and the Cochlea 88 5.5.1 The HPA Axis Signaling System 88 5.5.2 The Local Cochlear CRF-Signaling System 89 5.6 Stress and the Central Nervous System 90 5.7 Stress and Tinnitus 91 5.7.1 Stress Causing Tinnitus 92 5.7.2 Tinnitus Causing Stress 93 5.8 Recognizing Tinnitus in Animals? 94 5.8.1 Using Classical Conditioning 95 5.8.2 Using the Gap-Startle Response 96 5.9 Summary 98 References 98 6: Stress-Related Blood Biomarkers 101 6.1 Introduction 101 6.2 Neuroendocrine Biomarkers of Stress 103 6.2.1 Cortisol 103 6.2.2 Catecholamines: Dopamine, Epinephrine (Adrenaline), and Norepinephrine 105 6.3 Immune Biomarkers of Stress 105 6.3.1 Cytokines 107 6.3.1.1 Interleukin-1 Beta 107 6.3.1.2 Interleukin-6 109 6.3.1.3 Tumor Necrosis Factor Alpha 110 6.3.2 Thrombocytes (Platelets) 113 6.4 Neurotransmitters and Neurotrophins as Biomarkers of Stress 114 6.4.1 Serotonin (5-Hydroxytryptamine (5-HT)) 114 6.4.2 Neurotrophins: Brain-Derived Neurotrophic Factor (BDNF) 115 6.5 Other Biomarkers 117 6.5.1 Vitamin B12 117 6.5.2 Prestin 117 6.6 Biomarkers for the Diagnosis and Monitoring of Tinnitus 117 References 119 7: Psychometric Assessment of Tinnitus Patients Within Clinical Practice Settings 123 7.1 Conceptual Framework 123 7.2 Overview of Commonly Used Assessments 126 7.2.1 Patient-Reported Outcomes 126 7.2.1.1 Symptoms 126 7.2.1.2 Disease Impact 126 7.2.1.3 Health-Related Quality of Life 126 7.2.1.4 Global Quality of Life 127 7.2.2 Determinants 127 7.2.2.1 Comorbidities 127 7.2.2.2 Perceived Stress 129 7.2.2.3 Personalities 129 7.3 The Next Generation of Instruments 131 7.3.1 Common Metric 132 7.3.2 Individually Tailored Tests 133 7.3.3 Assessment Across Different Settings 133 7.4 Logistics 134 7.4.1 Mode of Assessment 134 7.4.2 Infrastructure 136 References 139 8: Stress-Related Tinnitus Treatment Protocols 144 8.1 Stress, Distress, and Tinnitus Suffering 145 8.2 The Psychological Nature of Tinnitus Suffering 147 8.3 The Cognitive Approaches 148 8.3.1 The Habituation Model 148 8.3.2 The Neurophysiological Model 149 8.3.3 The Cognitive Model 150 8.4 The Cognitive Behavioral Approach 151 8.5 Comparing the Models 152 8.6 Treatment Approaches for Tinnitus-Related Distress 154 8.6.1 The History of CBT 154 8.6.2 Tinnitus Retraining Therapy 155 8.6.3 Cognitive Therapy and Cognitive Behavioral Therapy 156 8.6.4 The Cognitive Approach 157 8.6.5 A Fear-Avoidance Approach 157 8.6.6 Comparing the Treatments 158 8.7 Measuring Tinnitus-Related Distress 160 8.7.1 Tinnitus Severity in Terms of Distress 160 8.7.2 Tinnitus Distress: The Psychological Constructs 162 8.7.2.1 Measuring Tinnitus Catastrophizing 163 8.7.2.2 Measuring Tinnitus-Related Fear 163 8.7.2.3 Measuring Increased Awareness of Tinnitus 163 8.7.2.4 Measuring Tinnitus Avoidance 164 8.7.2.5 Measuring Tinnitus Acceptance 164 8.7.2.6 Measuring Tinnitus-Related Disability 164 8.8 Take-Home Messages 164 Appendix 1 168 Appendix 2 169 Appendix 3 170 Appendix 4 171 References 172 9: Outcome Measures Associated with Perceived Stress 178 9.1 Clinical Trial Designs 178 9.2 Definition of Perceived Stress 180 9.3 Patient-Reported Complaints About Tinnitus 181 9.4 Measuring Perceived Stress Associated with Tinnitus 183 9.5 Associations Between Tinnitus and Psychological Well-Being 186 9.6 Measuring General Perceived Stress 187 9.7 Applications of Stress-Related Questionnaire Instruments 189 9.7.1 Use of Questionnaires for Diagnosing Perceived Stress 192 9.7.2 Use of Questionnaires for Evaluating Treatment-Related Change in People with Tinnitus 194 9.8 Take-Home Messages 201 References 202 This book provides up-to-date scientific information on the pathways by which psychosocial stress can affect the auditory system and describes current approaches to the management of patients with stress-related tinnitus. The latest evidence is presented on aspects such as the role of stress hormones in auditory function, the effects of allostatic load, circadian sensitivity to auditory trauma, and the association between stress-related biomarkers and tinnitus. The clinically oriented chapters discuss psychometric instruments of value in the tinnitus clinic and present stress-related tinnitus treatment protocols and outcome measures. It is widely acknowledged that the tinnitus percept acts as a stressor. However, it is also now evident that psychosocial stress can play a causative role in tinnitus and that the impact varies according to the level, duration, and quality of the stress. Assessment of the types and levels of stress in tinnitus patients before, during, and after treatment is therefore very important. Healthcare professionals attending tinnitus patients will benefit from the information that this book provides on the relationship between tinnitus and stress and from the practical guidance that it offers. This book provides up-to-date scientific information on the pathways by which psychosocial stress can affect the auditory system and describes current approaches to the management of patients with stress related tinnitus. The latest evidence is presented on aspects such as the role of stress hormones in auditory function, the effects of allostatic load, circadian sensitivity to auditory trauma, and the association between stress-related biomarkers and tinnitus. The clinically oriented chapters discuss psychometric instruments of value in the tinnitus clinic and present stress related tinnitus treatment protocols and outcome measures. It is widely acknowledged that the tinnitus percept acts as a stressor. However, it is also now evident that psychosocial stress can play a causative role in tinnitus and that the impact varies according to the level, duration, and quality of the stress. Assessment of the types and levels of stress in tinnitus patients before, during, and after treatment is therefore very important. Healthcare professionals attending tinnitus patients will benefit from the information that this book provides on the relationship between tinnitus and stress and from the practical guidance that it offers