Approximately 70 percent of patients seeking help for tinnitus present with symptoms of insomnia.1 It is not clear whether the degree of insomnia is directly related to tinnitus loudness or whether it is related to the psychological impact of tinnitus. Since complaints of sleeping problems are common among patients with tinnitus,2 it is important to further explore the mechanisms underlying the association between tinnitus loudness and sleep disturbances. To assess this relationship, our study used mediation analysis, which is a process of evaluating the direct and indirect effects of an independent variable (e.g., tinnitus loudness) on a dependent variable (e.g., insomnia). This is done by determining whether the relationship between the independent and dependent variables, shown as a regression coefficient, changes when other independent variables are included in the analysis. If the other variables change this relationship and if they are themselves related to the dependent variable, they are considered mediator variables.3
Previous research studies support the application of cognitive behavioral therapy (CBT) combined with sound therapy to the management of tinnitus. However, there is limited evidence on the effectiveness of audiologist-delivered CBT without sound therapy in improving sleep among people with tinnitus. In this article, we discuss the key findings of our recent study on tinnitus loudness and sleep disturbances, which aimed to evaluate (1) improvements in sleep quality after audiologist-delivered CBT and (2) patients’ perspectives about different aspects of CBT.
STUDY MATERIALS AND PROCEDURES
Assessment procedures. In our study, we asked participants to complete the following questionnaires: the Visual Analogue Scale (VAS) for tinnitus loudness and tinnitus annoyance, Tinnitus Handicap Inventory (THI), Insomnia Severity Index (ISI), Generalized Anxiety Disorder (GAD-7), and Patient Health Questionnaire (PHQ-9).
Participants also completed a feedback questionnaire at the end of the last planned session. They were asked to choose a number between one and 10 on a Likert numerical scale. The questions were:
- How effective was CBT in helping you manage your tinnitus? Number one is “not effective at all” and number 10 is “very effective.”
- Are you able to manage your tinnitus differently compared to before you started your treatment? Number one is “no” and number 10 is “yes, a lot.”
- Typically, CBT is offered at mental health settings within the U.K. National Health Service (NHS). However, your CBT was provided in an audiology department by audiologists who are specialized in tinnitus and hyperacusis rehabilitation. How acceptable was this to you? Number one is “not acceptable at all” and number 10 is “very acceptable.”
Treatment procedures. Audiologist-delivered CBT is broadly similar to CBT delivered by psychologists. It includes: (1) empathic listening informed by the client-centered counseling method; (2) development of a case formulation that explains the mechanism by which tinnitus leads to distress based on cognitive theory; (3) application of behavioral experiments to explore and modify negative thoughts and safety-seeking behaviors; and (4) diary keeping of thoughts and feelings to provide a structured method for patients to take notes of their tinnitus problems and associated thoughts and emotions.4,5 Table 1 shows a summary of the typical techniques used at each clinical meeting.
The study consisted of a two-phased retrospective cross-sectional clinical audit.
Phase 1. In phase one, we analyzed the data of 417 patients who consecutively sought treatment for tinnitus in a U.K.-based audiology clinic.6 Of these tinnitus patients, one-third also had hyperacusis (n = 134), a heightened sensitivity to certain sounds. The average age of the patients was 53 years old (standard deviation [SD] = 15 years), and 52 percent (215/417) were male. To explore the mechanisms underlying the relationship between tinnitus loudness and ISI scores, variables that significantly predicted insomnia in the stepwise multiple-regression model were included in a mediation analysis.6
Phase 2. We included the data for 29 consecutive adult patients who received a full course of audiologist-delivered CBT for tinnitus management.7 As part of their routine care, all patients completed a wide range of questionnaires before and after receiving audiologist-delivered CBT. Pre- and post-treatment scores on the ISI were compared to calculate its effect size.
RESULTS & DISCUSSION
Relationship between tinnitus loudness and insomnia. The outcomes of the mediation analysis are summarized in Figure 1. The regression coefficients (b) for the indirect effects of tinnitus loudness on insomnia were as follows: via depression (path “b” in Figure 1), b = 0.53 (p <0.001); via tinnitus annoyance (path “c” in Figure 1), b = 0.33 (p = 0.053); and via tinnitus handicap (path “e” in Fig. 1), b = 0.38 (p = 0.001). The coefficient for the total indirect effect was b = 1.23. The regression coefficient for the direct effect of tinnitus loudness on insomnia (path “d” in Figure 1) was only b = 0.11 (p = 0.57), a small and non-significant effect. To sum up, the relationship between tinnitus loudness and insomnia was fully mediated via depression and tinnitus handicap, probably with contribution from tinnitus annoyance.6
Audiologist-delivered CBT for tinnitus-related insomnia. The average age of the patients was 48 years old (SD = 14 years). The average number of CBT sessions was 5.9 (SD = 1.0). ISI scores ranged from 0 to 28. Based on the scores for the ISI, 10 percent (3/29) of patients did not have insomnia, 17 percent (5/29) had mild insomnia, 42 percent (12/29) had clinically significant insomnia, and 31 percent (9/29) had severe insomnia.
The mean score on the ISI was 17 (SD = 7) before the treatment, which was reduced (improved) to 10 (SD = 7) after treatment (p <0.001). The effect size of treatment was 0.92 (95% CI: 0.38 to 1.5). For the question, “How effective is CBT in helping you manage your tinnitus?” the median response was 8/10 (SD = 1.6), and 90 percent of patients rated the effectiveness of CBT as seven or above. For the question, “Are you able to manage your tinnitus differently compared to before you started your treatment?” the median response was 9/10 (SD = 1.4), and 87 percent of patients rated their ability to manage their tinnitus and/or hyperacusis as seven or above. For the question, “How acceptable was this [audiologist-delivered CBT] to you?” the median response was 10/10 (SD = 1.1), and 97 percent of the patients rated the acceptability of audiologist-delivered CBT as seven or above.7
Audiologist-delivered CBT is acceptable to patients as an effective tool to help manage tinnitus-related insomnia symptoms.
1. Aazh H, Baguley DM, Moore BCJ. Factors Related to Insomnia in Adult Patients with Tinnitus and/or Hyperacusis: An Exploratory Analysis. Journal of the American Academy of Audiology
. 2019;[Epub ahead of print].
2. Tyler RS, Baker JL. Difficulties experienced by tinnitus sufferers. Journal of Speech and Hearing Disorders
3. Baron RM, Kennedy DA. The moderator-mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of personality and social psychology
4. Aazh H, Moore BCJ. Proportion and characteristics of patients who were offered, enrolled in and completed audiologist-delivered cognitive behavioural therapy for tinnitus and hyperacusis rehabilitation in a specialist UK clinic. International journal of audiology
5. Aazh H, Moore BCJ. Effectiveness of audiologist-delivered cognitive behavioral therapy for tinnitus and hyperacusis rehabilitation: outcomes for patients treated in routine practice. American Journal of Audiolgy
6. Aazh H, Moore BCJ. Tinnitus loudness and the severity of insomnia: A mediation analysis. International journal of audiology
. 2019;Published online: 10 Jan 2019:1-5.
7. Aazh H, Bryant C, Moore BCJ. Patients’ perspectives about the acceptability and effectiveness of audiologist-delivered cognitive behavioral therapy for tinnitus and/or hyperacusis rehabilitation. American journal of audiology