Emotional Exhaustion as a Predictor of Tinnitus

Binaural hearing was tested using a tonal audiogram (500– 8,000 Hz) and speech-in-noise test using circumaural headphones (TDH39). ULL was measured in decibels hearing level at the frequencies 0.5, 1, 2 and 4 kHz in both left and right ears separately beginning at 70 dB and increasing the intensity in 5-dB steps until the study participant indicated uncomfortable loudness. Hearing status was defined as no hearing loss in tonal audiometry and speech-in-noise test (0). A hearing loss was 6 20 dB HL at any frequency in the tonal audiometry or 6 6 dB HL in the speech-in-noise test (1), threshold elevation of 6 20 dB HL at any frequency in the tonal audiometry and of 6 6 dB HL in the speechin-noise test (2). Exposure to noise at work was measured on a ratio scale by asking participants what proportion of time they were exposed to weary noise (from 0 = never to 6 = all or almost all the time). The outcomes were ‘any tinnitus’ and ‘severity of tinnitus’. Any tinnitus was defined as a ‘yes’ response (sometimes, often or always) to the question ‘Have you recently experienced a sound in one or both ears that was not from an external source (called tinnitus) which lasted for more than five minutes? ’ Severity of tinnitus was the mean total score on the Tinnitus Handicap Questionnaire (THQ) comprising 26 questions [5] . It was slightly modified structurally as verbal rating scales were used instead of Likert scales. EE was assessed with the exhaustion subscale of the Oldenburg Burnout Inventory [6] . Coping was assessed using a modified version of Carver’s [7] brief COPE inventory. The overall prevalence of any tinnitus was 31% in our 348 participants, of whom 11% reported severe tinnitus. Gender-stratified analyses were conducted (n = 282, 66 missing values from any one of the variables). A logistic regression analysis was run with the dependent variable ‘tinnitus prevalence’ (yes/no) and ‘age’ (in years), ‘education’ (1–4), ‘sex’ (men/women), ‘hearing status’ in the left and right ears respectively (0–2), exposure to work-related noise (0–6), ULL (in dB), EE and coping as independent variables. All variables were included in one single step ( table 1 ). The analyses of men demonstrated that hearing loss, ULL, coping and EE were all significant predictors of tinnitus prevalence. The other variables were not significantly associated with tinnitus. The women exhibited a somewhat different pattern and significant predictors were hearing loss, noise at work, ULL and EE. In contrast to the men, coping was not a significant predictor of tinnitus prevalence. A linear regression was performed with THQ mean score as the dependent variable and age and education as covariates in a first step (enter). Hearing loss, ULL, work-related noise exposure and exhaustion were included as predictors in a second step (enter). The ANOVA was statistically significant (left ear: F = 3.67 df = 7 , p ! 0.01; right ear: F = 3.07 df = 7 , p ! 0.01) and the whole model explained 16% of the variance for the left ear and 13% for the right ear. The only significant predictors of the mean THQ score for the left ear were ULL (standardized = –0.20, p = 0.04) and exhausRecently, Hasson et al. [1] found strong and almost linear associations between self-reported hearing difficulties (no hearing problems, either tinnitus or hearing loss, or both) and stress factors. However, there is a need to have a better understanding of possible contributions of hearing, health and physical factors such as noise exposure to both the presence and severity of tinnitus. The aim of the present study was to assess possible associations between hearing status (hearing loss and noise exposure) and health (sleep quality, life satisfaction, depression and coping) in relation to tinnitus. We used uncomfortable loudness levels (ULL) as an objective measure of hyperacusis, which is a reduced sound tolerance and found in about 80% of individuals with tinnitus [2] . Emotional exhaustion (EE), the experience of feeling drained of energy due to prolonged stress, was included, for the first time, as a predictor for tinnitus. The present study is cross-sectional and includes subjective and objective measures of hearing, as well as subjective ratings of EE. A more complete description of the sample can be found in Benka Wallén et al. [3] . Briefly, the sample was drawn from the Swedish Longitudinal Occupational Survey of Health (SLOSH) [4] . The sample of the present study was based on two types of inclusion criteria: (1) degree of EE and (2) living in the greater Stockholm area. The selection of participants was based on scorings on the exhaustion dimension on the Maslach Burnout Inventory – General Survey. The strategy chosen was to select contrasting groups with the highest exhaustion scores, medium EE and those with the lowest EE scores. The final cohort size was thus 671. After two reminders, 348 (52%) individuals enrolled in the study. All gave their written consent to participate and the study was approved by the local ethics committee in Stockholm (protocol No. 2009/493-31/3). Questionnaires were used to assess the participants’ general demographics, mental health (e.g., depressive symptoms, EE), hearing status (e.g., tinnitus, hearing loss), life satisfaction, sleep quality and coping. Received: June 15, 2011 Accepted after revision: November 13, 2011 Published online: August 1, 2012