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A cohort study of patients with tinnitus and sensorineural hearing loss in a Swedish population
Auris Nasus Larynx 40 (2013) 41–45
Contents lists available at SciVerse ScienceDirect
Auris Nasus Larynx journal homepage: www.elsevier.com/locate/anl
A cohort study of patients with tinnitus and sensorineural hearing loss in a Swedish population Reza Zarenoe, Torbjo¨rn Ledin * Division of Oto-Rhino-Laryngology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linko¨ping University, Linko¨ping, Sweden
A R T I C L E I N F O
A B S T R A C T
Article history: Received 24 October 2011 Accepted 5 May 2012 Available online 29 May 2012
Objective: We aimed to describe a large cohort of patients with tinnitus and sensorineural hearing loss (SNHL) in Sweden, and also to explore the possibility of finding potential possible differences between various diagnoses within SNHL. It is also of great interest to see how a multidisciplinary team was used in the different subgroups and the frequency of hearing aids use in patients with tinnitus. ¨ stergo¨tland County, Methods: Medical records of all patients who had received the diagnosis SNHL in O Sweden between 2004 and 2007 were reviewed. Patients between 20 and 80 years with tinnitus and a pure tone average (PTA) lower than 70 dB HL were included in the study. Patients were excluded from the analyses if they had a cochlear implantation, middle ear disorders or had a hearing loss since birth or childhood. The investigators completed a form for each included patient, covering background facts, and audiograms taken at the yearly check up. Results: Of a total 1672 patients’ medical record review, 714 patients were included. The majority of patients (79%) were in the age group over 50 years. In male patients with bilateral tinnitus, the PTA for the left ear was significantly higher than for the right ear. The results regarding the configuration of hearing loss revealed that 555 patients (78%) had symmetric and 159 (22%) asymmetric hearing loss. Retrocochlear examinations were done in 372 patients and MRI was the most common examination. In all patients, 400 had no hearing aids and out of those 220 had unilateral tinnitus and 180 patients had bilateral tinnitus. 219 patients had a PTA > 20 dB HL and did not have any hearing aid. Results demonstrated that the Stepped Care model was not used widely in the daily practice. In our study, patients with bilateral-, unilateral hearing loss or Mb Me´nie`re were the most common patients included in the Stepped Care model. Conclusion: In a large cohort of patients with SNHL and tinnitus, despite their hearing loss only 39% had hearing aids. It was observed that the medical record review often showed a lack of information about many background factors, such as; patients’ general health condition, which could be a quality factor that needs improvement. Our results show that the Stepped Care model could be an effective option for providing a better access for tinnitus-focused treatment, although the number of patients in this study who were included in the Stepped Care model was low. ß 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Tinnitus Sensorineural hearing loss Hearing aids Retrocochlear examinations
1. Introduction Tinnitus is a distressing otological disorder that may cause various somatic and psychological problems. The overall prevalence of tinnitus in the general adult population is about 10–15%, with 1–3% of the population having severe, distressing tinnitus [1]. Aging increases the prevalence of tinnitus [2] with the peak age range of patients with tinnitus being 40–70 years [3]. The American Tinnitus Association has reported a prevalence of 19%
* Corresponding author at: Division of Oto-Rhino-Laryngology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linko¨ping University, University Hospital, SE 58183, Linko¨ping, Sweden. Tel.: +46 10 1032526. E-mail address: [email protected] (T. Ledin). 0385-8146/$ – see front matter ß 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.anl.2012.05.005
in the American population, which increases with age and the degree of hearing impairment [4]. In addition to the age-related change in prevalence, tinnitus has been reported to be more prevalent in men than in women. This difference could be related to higher hearing thresholds in the male population [4]. Furthermore, unilateral tinnitus has been reported to be more common in the left ear [5,6]. Tinnitus patients often state that they experience hearing loss. This is usually a sensorineural impairment, cochlear or retrocochlear, and can be due to aging, being exposed to noise, or using ototoxic drugs etc. [2,7]. The diagnosis sensorineural hearing loss (SNHL) includes a variety of diagnoses such as: Mb Me´nie`re, vestibular schwannoma, ototoxic damage, presbyacusis, and sudden sensorineural hearing loss (sudden deafness).
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R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
Unilateral sensorineural hearing loss associated with tinnitus and/or vertigo can be a sign of a vestibular schwannoma. Thus, patients with asymmetric hearing loss and/or unilateral associated symptoms should undergo examinations to rule out a retrocochlear cause. Such examinations can be auditory brainstem response audiometry (ABR) or magnetic resonance imaging (MRI). An MRI scan has been shown to be a cost effective method of investigation in patients with unilateral SNHL, tinnitus, and vertigo compared to ABR [8,9]. Amplification of sound using hearing aids can increase the level of neural activity, reducing the gap between the tinnitus and the background neural activity [10]. Hearing aids have been used for many years in patients suffering from tinnitus in combination with hearing impairment. Despite the obvious benefits of using hearing aids there are many patients with hearing loss who do not consider hearing aids as a treatment option [11]. The management of adults ¨ stergo¨tland County with tinnitus in the two ENT clinics in O (population around 400,000) consists of a detailed evaluation before specific treatment routines are applied. A multidisciplinary team approach, using a team consisting of otolaryngologist, audiologist, psychologist, and a rehabilitation counselor, is used to meet the needs of the patient. The treatment strategy used is called the Stepped Care model. It contains an audiological consultation and hearing aid fitting, if a hearing loss is found (step 1), an information meeting (step 2), and cognitive behavioral therapy (CBT) or individual therapy by a psychologist (step 3). But unfortunately not all patients are brought into the system in this way. Some patients join the Stepped Care model after a visit to the ENT-doctor or while a hearing aids fitting is in progress. Most prevalence studies have investigated each diagnosis within SNHL separately to see whether the presence of tinnitus is restricting the patients’ life, and if there is a relationship between tinnitus and SNHL [12]. However, they have not addressed the findings in the whole SNHL group which is the more realistic situation that an ENT-clinic is there to meet. To our knowledge, there is no study that has examined possible differences in the prevalence of tinnitus between various diagnoses within SNHL. The aim of this study is to describe a large cohort of patients with tinnitus and SNHL in Sweden, and also to analyze the potential differences in examination methods and treatment models in different subgroups. 2. Materials and methods The investigation is a retrospective, descriptive study based on data from patients who sought care for tinnitus and hearing loss at ¨ stergo¨tland County, Sweden during 2004– the two ENT clinics in O 2007 and got a diagnostic code at the same time. The study is approved by the regional ethical review board in Linko¨ping, Sweden (Dnr M214-07). The time period was chosen because the multidisciplinary team started in 2004 and remained a complete team until the spring of 2008. A nurse and a physiotherapist left the team at that time which limited the possibilities to offer patients a complete set of treatment options. Patients’ hearing loss was classified as a unilateral hearing loss when one of the ears was within normal limits, i.e. pure tone average (PTA) was 20 dB HL, and the PTA of the other ear was >20 dB HL. Bilateral hearing loss was defined as a hearing loss where PTA for both ears was >20 dB HL and could either be symmetric or asymmetric hearing loss. A hearing loss was classified as an asymmetric hearing loss if the difference between the PTA for both ears was larger than 15 dB HL. All classifications were made at the first visit by the ENT-doctors, based on patients’ audiograms. The investigators completed a form for each patient, covering background information, and audiograms taken at the
yearly check up. The background information contained data about the patient’s tinnitus, vertigo, hearing loss, diagnosis, further audiological examinations, treatment of tinnitus, heredity for tinnitus, concomitant diseases and medication. 2.1. Inclusion and exclusion criteria Medical records for all patients who had sought care for hearing problems during the study period and were diagnosed with sensorineural hearing loss were reviewed. Information from the ENT clinics’ medical records occasionally did not contain the Audiologist information obtained in the clinics, thus additional information was collected from the patients audiology case records. Patients between 20 and 80 years of age with tinnitus and a PTA ¨ stergo¨tland, lower than 70 dB HL were included in the study. In O patients with a PTA > 70 dB HL could be candidates for cochlea implants (CI) and were thereby not included in this study. Because of their profound hearing loss, these patients have severe problems. Therefore, there are normally other rehabilitation plans that are developed and handled by the CI-team. Patients were excluded from the analyses if they had a CI, middle ear disorders, or a hearing loss since birth/childhood. Multi-handicapped patients and those who did not speak fluent Swedish and had an interpreter at the ENT visit were also excluded. 2.2. Statistics Data were registered in Microsoft Office Excel. Distribution of patients between groups with two or more possible states was evaluated using Chi2 test, and in the 2 2 case Yates’ correction was used. Measurement variables were compared between groups with Student’s t-test. The level of significance was set at p < 0.05. 3. Results 3.1. Patient characteristics Medical record review of total 1672 patients with SNHL demonstrated that 1175 (70%) patients also had tinnitus (Fig. 1). An additional 446 patients (27%) were excluded because they did not experience tinnitus. Information about the frequency of occurrence of tinnitus was missing for 51 patients (3%), and those patients were thereby excluded from the analyses. Out of 1175 patients with both SNHL and tinnitus, 461 patients (39%) were excluded because they had a PTA > 70 dB HL or had a cochlear implantation, middle ear disorders, hearing loss since birth/ childhood, and/or could not speak fluent Swedish. The remaining 714 patients had SNHL with tinnitus, and fulfilled the specific inclusion criteria. The group consisted of more male patients (n = 388; 54%) than female (n = 326; 46%). The difference was significant (p = 0.02). The majority of patients were older than 50 years (Table 1). In patients with unilateral tinnitus, the prevalence of tinnitus in the left ear was higher (p < 0.001). In addition, the PTA for the left ear was significantly higher than for the right ear in male patients (p = 0.01) but not in females (p = 0.45). In all, 402 patients (56%) were diagnosed with bilateral SNHL, 151 (21%) with unilateral SNHL, and 161 (23%) with various diagnoses; 113 (16%) Mb Menie`re´, 32 (4%) sudden sensorineural hearing loss (SSHL), 9 (1%) noise-inducted SNHL, 5 (0.7%) presbyacusis, and 2 (0.2%) cochlear otosclerosis. There was an absence of information about patients’ vertigo in 47% of the medical records. The characteristics data for patients with unilateral vs. bilateral tinnitus are described in Table 1. There were more men than
R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
43
Medical record review N=1672 Paents diagnosed with “sensorineural hearing loss”
Included N=714
Excluded N=958
Paents with SNHL AND nnitus
SNHL AND unilateral nnitus n=358
SNHL AND bilateral nnitus n=356
PTA >70 dB HL n=461
SNHL without nnitus/periodic nnitus n=446
Medical records without informaon about nnitus n=51
Fig. 1. Study flowchart.
women among patients with bilateral tinnitus (p = 0.05). Out of 388 male patients; 65 had tinnitus on the right ear, 116 on the left ear and 207 patients had bilateral tinnitus. In female patients, 82 had tinnitus on the right ear, 95 on the left ear and 149 had bilateral tinnitus.
Patients with asymmetric hearing loss (61%) underwent retrocochlear examinations in a higher extent than patients with symmetric hearing loss (50%, p = 0.014). 105 patients underwent nystagmography and 54 patients had nystagmography in combination with MRI and/or ABR.
3.2. Examinations
3.3. Treatment
The PTA for the left ear compared to the right ear in patients with unilateral tinnitus showed no significant difference (p = 0.09). In patients with bilateral tinnitus, the left ear had higher PTA (p = 0.007). The results regarding the configuration of hearing loss revealed that 555 patients (78%) had symmetric and 159 (22%) asymmetric hearing loss. High frequency hearing loss was found to be more common (around 92%) in patients with symmetric hearing loss (Table 2). Retrocochlear examinations were done in 372 patients and MRI was the most common examination (Table 3). There was a significant difference between patients with unilateral tinnitus and bilateral tinnitus regarding use of the MRI examination (p = 0.001).
The results showed that 314 patients had hearing aids. There were no significant differences between male and female patients. Of those 400 without hearing aids, 220 patients had unilateral tinnitus and 180 bilateral tinnitus (Table 4). There were significantly more patients with bilateral tinnitus (49%) having hearing aids compared to patients with unilateral tinnitus (39%, p = 0.02). Two hundred and nineteen patients with a best ear PTA > 20 dB, did not have any hearing aid. Among those, 138 patients had unilateral tinnitus, and 81 patients bilateral tinnitus. The difference between these groups was significant (p < 0.001). For further analyses of how the Stepped Care model was used in the three largest diagnoses within SNHL, see Table 5. All patients were examined by an ENT doctor and 135 (20%) of them met an audiologist, with tinnitus training, for further treatment. Among
Table 1 Distribution of characteristics of patients with SNHL and tinnitus (n = 714). Bilateral tinnitus (n = 356) n (%)
Unilateral tinnitus (n = 358) n (%)
Total (n = 714) n (%)
149 (42) 28.4 15.9 31.1 16.6 207 (58) 30.7 16.9 31.1 16.6
177 (49) 24.7 15.2 26.7 14.5 181 (51) 27.2 16.1 29.4 15.8
326 (46) 26.7 16.6 29.1 15.8 388 (54) 28.9 16.4 30.2 16.0
<30 31–40 41–50 51–60 61–70 71–80
9 (2) 19 (5) 37 (10) 87 (25) 115 (33) 89 (25) 61.1 12.7
6 (2) 18 (5) 43 (12) 84 (23) 122 (34) 85 (24) 61.3 12.6
15 (2) 37 (5) 80 (11) 171 (24) 237 (34) 174 (24) 61.3 12.7
PTA (dB HL) (mean SD)
Right ear Left ear
29.6 14.9 31.3 15.1
26.4 17.6 28.3 16.7
28.0 14.8 29.5 10.6
Hearing aid
Bilateral Unilateral None
114 (32) 62 (17) 180 (51)
57 (16) 81 (23) 220 (61)
171(24) 143 (20) 400 (56)
Variables Gender and PTA (dB HL) (mean SD)
Female Right ear Left ear Male Right ear Left ear
Age group (year)
Age (mean SD)
R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
44
Table 2 Tinnitus and audiogram shape. Subjects with symmetrical hearing loss combined with unilateral or bilateral tinnitus (n = 555). Audiogram shape
n (%)
Low frequency loss Mid frequency loss High frequency loss Flat loss
4 9 509 33
4. Discussion Tinnitus is common in patients with SNHL [2,7]. Results of this study could verify that 70% of all patients who were diagnosed ¨ stergo¨tland County had tinnitus. Clinical informawith SNHL in O tion in patient’s records can be defined as ‘‘the commodity used to help make patient care decisions’’ [13]. Most of the information physicians obtain during a patient’s visit stay in physicians heads; ‘‘a constantly expanding and reinterpreted database’’ [14]. This could obviously interfere with an optimal care plan for the patients. After our first patient medical record review we found that there were notes in many patients’ records that the patients had stated to have constant tinnitus, but yet had not received a registered tinnitus diagnosis. In spite of this; they were of course included in our study. Our results showed that there was often lack of information not only about vertigo, tinnitus and heredity but also information about patients’ other diseases and general health. We have some hesitation concerning if all patients received an adequate diagnosis, given the very small sizes of some of the subgroups. It is possible that patients, who got a diagnosis of bilateral SNHL, could in fact have been classified as presbyacusis or noise-conducted hearing loss. In this study, the majority of patients were men (54%). This is not consistent with findings of Nondahl et al. [15]. They found the prevalence of tinnitus being higher among female patients. A possibility is that more male patients in our study have been working in noisy environments as we have observed that men in average had a little higher PTA values. Tinnitus is a common condition among older adults. Hoffman and Reed compared the prevalence of self-reported tinnitus from several large epidemiologic studies [16]. For those aged 50 years and older, the estimated prevalence of tinnitus ranged from 7.6% to 20.1%. In our study, we found that 79% of patients were older than 50 years, which has been reported in other studies [4]. Several reports as well as this study found unilateral tinnitus to be more common in the left ear [5,6], especially in male patients. Unfortunately, there is no explanation for how this phenomenon occurs. Tinnitus is often associated with some degree of hearing loss, usually high frequency hearing loss related to cochlear damage [6]. In the present study, high frequency hearing loss was also more represented. Unilateral SNHL associated with tinnitus and/or vertigo can be a sign of retrocochlear lesion, therefore these patients should be examined using retrocochlear examinations [17]. Of 159 patients with asymmetric SNHL, 61% were investigated by retrocochlear examinations. Of 357 patients with unilateral tinnitus, the corresponding figure was 64%. The extent of these examinations should ideally be 100%, since this is highly recommended in order
(0.7) (1.6) (91.7) (6.0)
Table 3 The most common retrocochlear examinations for patients with asymmetric- and symmetric hearing loss (n = 714). Examinations
MRI n (%)
ABR n (%)
Asymmetric SNHL and unilateral tinnitus (n = 103) Asymmetric SNHL and bilateral tinnitus (n = 56) Symmetric SNHL and unilateral tinnitus (n = 254) Symmetric SNHL and bilateral tinnitus (n = 301)
37 (36)
21 (20)
MRI/ABR n (%) 8 (8)
20 (36)
9 (16)
2 (4)
86 (34)
55 (22)
20 (8)
52 (17)
46 (15)
16 (5)
Table 4 Tinnitus and hearing aids (n = 714). n (%) Unilateral tinnitus (n = 358) With unilateral hearing aid With bilateral hearing aids Without hearing aid? PTA 20 dB HL PTA >20 dB HL
81 (23) 57 (16) 220 (61) 82 (37) 138(63)
Bilateral tinnitus (n = 356) With unilateral hearing aid With bilateral hearing aids Without hearing aid? PTA 20 dB HL PTA >20 dB HL
62 (17) 114 (32) 180 (51) 99 (55) 81(45)
those, 83 patients participated in the group information (61% of the patients who visited a tinnitus trained audiologist). Of all patients, 105 participated in the comprehensive group information on tinnitus, which is the step 2 in the Stepped Care model. The results show that after the step 2 there were 75 patients (71% of the participants in step 2) who needed further treatment in the third step. In total there were; 55 patients who visited a registered physical therapist (RPT), 35 a counselor and 31 a psychologist. CBT was used in 23 patients; 3 patients with Mb Me´nie`re, 13 with bilateral SNHL and 7 with unilateral SNHL.
Table 5 Distribution of characteristics of the three largest diagnoses (n = 714). Tinnitus
Bilateral Sensorineural Hearing loss (n = 402) Unilateral Sensorineural Hearing loss (n = 151) Mb Menie´re` (n = 113) a b c d e f
Hearing aid
The Stepped Care model a
RPT
c
Counselor
d
CBT
e
Unilat.
Bilat.
Unilat.
None
Group info
251
151
118
79
205
73
55
32
16
13
5
110
41
20
38
93
24
20
14
13
7
3
43
70
26
19
68
8
8
4
5
3
1
Comprehensive group information on tinnitus. Personal counseling by trained audiologist in tinnitus. Registered physical therapist. Counselor. Cognitive behavioral therapy. Psychologist consultation.
Audioloist
b
Bilat.
Psychologist
f
R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
to find all patients with e.g. a vestibular schwannoma. A recent study showed that 10% of patients with asymmetric SNHL are likely to have causative lesions found on MRI [18]. A majority of our patients (56%) did not have hearing aids, and this is similar to what has been reported in other studies [11]. It is likely that every patient with hearing loss was offered a hearing aid. There are many possible explanations for why the number of patients with hearing aids was so low. The stigma associated with hearing aid use, the limitations of amplification to remediate the fundamental difficulty of understanding speech in background noise, and also the economic issue [19]. In this study, a reason for patients not having hearing aids could be that most of them had a high frequency hearing loss and could, in quiet environments, handle a conversation in spite of their hearing impairment. The number of men who did not have any hearing aids was larger than in women, but no significant difference was found. Another hypothesis is that many patients might have difficulty accepting the fact that they need a hearing aid, especially men. Jerram and Purdy reported a greater use of hearing aids in patients with impaired hearing who accepted their hearing loss to a greater extent than in patients who denied their condition. In addition, patients who had higher pre-fitting expectations did not use their hearing aids to the same extent [20]. In the Stepped Care model, more expensive or time requiring treatments, which involve more resources (for example CBT), are reserved for patients who do not respond well to conventional treatments (for example hearing aid fitting). A multidisciplinary approach ‘‘provides a broad and detailed account of the recent developments in tinnitus research and clinical management’’ [1]. Our results show that the Stepped Care model could be effective for providing a better access for tinnitus-focused treatment in different levels and can make more resources available for patients with severe problems. An estimation from our data could be that 61% went from step 1 to step 2, whereas 71% continued from step 2 to step 3, giving a total number of 43% of all patients in step 1 who need the most resource consuming treatments. Thus patients in this way can reach their optimal level of care quicker no matter if they have unilateral or bilateral tinnitus. Patients, who were referred to the tinnitus team, could receive care adequately, by participating in the group information and getting in contact with other healthcare professions. A drawback in our study is that the number of patients who were included in the Stepped Care model was low. This could depend on lack of knowledge in ENT-doctors about how the Stepped Care model works. A more desirable model is of course that an audiologist, with tinnitus training, is the main first care giver for patients with tinnitus and hearing loss. Tinnitus sensation is for some of these patients associated with many adverse effects like depression, sleep disorders and even health problems. In addition to this cohort descriptive study, a study with focus on patients’ general health would be desirable. Such a study is ongoing. 5. Conclusion In a large cohort of patients with SNHL and tinnitus, we have investigated patterns of diagnostic procedures and treatments. The spite of hearing loss, only 44% of patients had hearing aids. In the designed Stepped Care program, only a few patients seem to need the more advanced treatments, like CBT. It was observed that
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medical record review often shows a lack of information about many background factors, such as; patients’ general health condition, which could be a quality factor that needs improvement. Conflict of interest None. The authors have no relevant financial interest in this article. Funding ¨ stergo¨tland, Gunnar Arnbrinks Stiftelse, The County Council of O and Linko¨pings La¨karesa¨llskap. Acknowledgment Financial support for this study has been received from the ¨ stergo¨tland, Gunnar Arnbrinks Stiftelse, and County Council of O Linko¨pings La¨karesa¨llskap. We thank all ENT-doctors, audiologists and administrative personnel who helped us gather our data. References [1] Andersson G, Baguley D, McKenna L. Tinnitus: A Multidisciplinary Approach. London: Whurr Publishers; 2005. [2] Sindhusake D, Mitchell P, Newall P, Golding M, Rochtchina E, Rubin G. Prevalence and characteristics of tinnitus in older adults: the blue mountains hearing study. Int J Audiol 2003;42:289–94. [3] Noell CA, Meyerhoff WL. Tinnitus: diagnosis and treatment of this elusive symptom. Geriatrics 2003;58:28–34. [4] Heller AJ. Classification and epidemiology of tinnitus. Otolaryngol Clin North Am 2003;36:239–48. [5] Meikle MB, Vernon J, Johnson RM. The perceived severity of tinnitus. Some observations concerning a large population of tinnitus clinic patients. Otolaryngol Head Neck Surg 1984;92:689–96. [6] Erlandsson SI, Hallberg LRM, Axelsson A. Psychological and audiological correlates of perceived tinnitus severity. Audiology 1992;31:168–79. [7] Sindhusake D, Golding M, Wigney D, Newall P, Jakobsen K, Mitchell P. Factors predicting severity of tinnitus: a population-based assessment. J Am Acad Audiol 2004;15:269–80. [8] Rupa V, Job A, George M, Rajshekhar V. Cost-effective initial screening for vestibular schwannoma: auditory brainstem response or magnetic resonance imaging? Otolaryngol Head Neck Surg 2003;128:823–8. [9] Teppo H, Heikkinen J, Laitakari K, Alho OP. Diagnostic delays in vestibular schwannoma. J Laryngol Otol 2009;123:289–93. [10] Parra LC, Pearlmutter BA. Illusory percepts from auditory adaptation. J Acoust Soc Am 2007;121:1632–41. [11] Aazh H, Moore BCJ, Roberts P. Patient-centered tinnitus management tool: a clinical audit. Am J Audiol 2009;18:7–12. [12] Sakata T, Esaki Y, Yamano T, Sueta N, Nakagawa T. A comparison between the feeling of ear fullness and tinnitus in acute sensorineural hearing loss. Int J Audiol 2008;47:134–40. [13] Wyatt J. Medical informatics, artefacts or science? Methods Inf Med 1996;35:197–200. [14] Tanenbaum SJ. Knowing and acting in medical practice: the epistemological politics of outcomes research. J Health Polit Policy Law 1994;19:27–44. [15] Nondahl DM, Cruickshanks KJ, Dalton DS, Klein BEK, Klein R, Schubert CR, et al. The impact of tinnitus quality of life in older adults. J Am Acad Audiol 2007;18:257–66. [16] Haffman H, Reed GW. Epidemiology of tinnitus. In: Snow JB, editor. Tinnitus: Theory and Management. Lewiston, NY: BC Decker Inc.; 2004. p. 16–41. [17] Turner RG, Shepard NT, Frazer GJ. Clinical performances of audiological and related diagnostic tests. Ear Hear 1984;5:187–94. [18] Cueva RA. Auditory brainstem response versus magnetic resonance imaging for the evaluation of asymmetric sensorineural hearing loss. Laryngoscope 2004;114:1686–92. [19] Kochkin S. Marketrak vii: obstacles to adult non-user adoption of hearing aids. Hear J 2007;60:24–51. [20] Jerram JCK, Purdy SC. Technology, expectations, and adjustment to hearing loss: predictors of hearing aid outcome. J Am Acad Audiol 2001;12:64–79.
Contents lists available at SciVerse ScienceDirect
Auris Nasus Larynx journal homepage: www.elsevier.com/locate/anl
A cohort study of patients with tinnitus and sensorineural hearing loss in a Swedish population Reza Zarenoe, Torbjo¨rn Ledin * Division of Oto-Rhino-Laryngology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linko¨ping University, Linko¨ping, Sweden
A R T I C L E I N F O
A B S T R A C T
Article history: Received 24 October 2011 Accepted 5 May 2012 Available online 29 May 2012
Objective: We aimed to describe a large cohort of patients with tinnitus and sensorineural hearing loss (SNHL) in Sweden, and also to explore the possibility of finding potential possible differences between various diagnoses within SNHL. It is also of great interest to see how a multidisciplinary team was used in the different subgroups and the frequency of hearing aids use in patients with tinnitus. ¨ stergo¨tland County, Methods: Medical records of all patients who had received the diagnosis SNHL in O Sweden between 2004 and 2007 were reviewed. Patients between 20 and 80 years with tinnitus and a pure tone average (PTA) lower than 70 dB HL were included in the study. Patients were excluded from the analyses if they had a cochlear implantation, middle ear disorders or had a hearing loss since birth or childhood. The investigators completed a form for each included patient, covering background facts, and audiograms taken at the yearly check up. Results: Of a total 1672 patients’ medical record review, 714 patients were included. The majority of patients (79%) were in the age group over 50 years. In male patients with bilateral tinnitus, the PTA for the left ear was significantly higher than for the right ear. The results regarding the configuration of hearing loss revealed that 555 patients (78%) had symmetric and 159 (22%) asymmetric hearing loss. Retrocochlear examinations were done in 372 patients and MRI was the most common examination. In all patients, 400 had no hearing aids and out of those 220 had unilateral tinnitus and 180 patients had bilateral tinnitus. 219 patients had a PTA > 20 dB HL and did not have any hearing aid. Results demonstrated that the Stepped Care model was not used widely in the daily practice. In our study, patients with bilateral-, unilateral hearing loss or Mb Me´nie`re were the most common patients included in the Stepped Care model. Conclusion: In a large cohort of patients with SNHL and tinnitus, despite their hearing loss only 39% had hearing aids. It was observed that the medical record review often showed a lack of information about many background factors, such as; patients’ general health condition, which could be a quality factor that needs improvement. Our results show that the Stepped Care model could be an effective option for providing a better access for tinnitus-focused treatment, although the number of patients in this study who were included in the Stepped Care model was low. ß 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Tinnitus Sensorineural hearing loss Hearing aids Retrocochlear examinations
1. Introduction Tinnitus is a distressing otological disorder that may cause various somatic and psychological problems. The overall prevalence of tinnitus in the general adult population is about 10–15%, with 1–3% of the population having severe, distressing tinnitus [1]. Aging increases the prevalence of tinnitus [2] with the peak age range of patients with tinnitus being 40–70 years [3]. The American Tinnitus Association has reported a prevalence of 19%
* Corresponding author at: Division of Oto-Rhino-Laryngology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linko¨ping University, University Hospital, SE 58183, Linko¨ping, Sweden. Tel.: +46 10 1032526. E-mail address: [email protected] (T. Ledin). 0385-8146/$ – see front matter ß 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.anl.2012.05.005
in the American population, which increases with age and the degree of hearing impairment [4]. In addition to the age-related change in prevalence, tinnitus has been reported to be more prevalent in men than in women. This difference could be related to higher hearing thresholds in the male population [4]. Furthermore, unilateral tinnitus has been reported to be more common in the left ear [5,6]. Tinnitus patients often state that they experience hearing loss. This is usually a sensorineural impairment, cochlear or retrocochlear, and can be due to aging, being exposed to noise, or using ototoxic drugs etc. [2,7]. The diagnosis sensorineural hearing loss (SNHL) includes a variety of diagnoses such as: Mb Me´nie`re, vestibular schwannoma, ototoxic damage, presbyacusis, and sudden sensorineural hearing loss (sudden deafness).
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R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
Unilateral sensorineural hearing loss associated with tinnitus and/or vertigo can be a sign of a vestibular schwannoma. Thus, patients with asymmetric hearing loss and/or unilateral associated symptoms should undergo examinations to rule out a retrocochlear cause. Such examinations can be auditory brainstem response audiometry (ABR) or magnetic resonance imaging (MRI). An MRI scan has been shown to be a cost effective method of investigation in patients with unilateral SNHL, tinnitus, and vertigo compared to ABR [8,9]. Amplification of sound using hearing aids can increase the level of neural activity, reducing the gap between the tinnitus and the background neural activity [10]. Hearing aids have been used for many years in patients suffering from tinnitus in combination with hearing impairment. Despite the obvious benefits of using hearing aids there are many patients with hearing loss who do not consider hearing aids as a treatment option [11]. The management of adults ¨ stergo¨tland County with tinnitus in the two ENT clinics in O (population around 400,000) consists of a detailed evaluation before specific treatment routines are applied. A multidisciplinary team approach, using a team consisting of otolaryngologist, audiologist, psychologist, and a rehabilitation counselor, is used to meet the needs of the patient. The treatment strategy used is called the Stepped Care model. It contains an audiological consultation and hearing aid fitting, if a hearing loss is found (step 1), an information meeting (step 2), and cognitive behavioral therapy (CBT) or individual therapy by a psychologist (step 3). But unfortunately not all patients are brought into the system in this way. Some patients join the Stepped Care model after a visit to the ENT-doctor or while a hearing aids fitting is in progress. Most prevalence studies have investigated each diagnosis within SNHL separately to see whether the presence of tinnitus is restricting the patients’ life, and if there is a relationship between tinnitus and SNHL [12]. However, they have not addressed the findings in the whole SNHL group which is the more realistic situation that an ENT-clinic is there to meet. To our knowledge, there is no study that has examined possible differences in the prevalence of tinnitus between various diagnoses within SNHL. The aim of this study is to describe a large cohort of patients with tinnitus and SNHL in Sweden, and also to analyze the potential differences in examination methods and treatment models in different subgroups. 2. Materials and methods The investigation is a retrospective, descriptive study based on data from patients who sought care for tinnitus and hearing loss at ¨ stergo¨tland County, Sweden during 2004– the two ENT clinics in O 2007 and got a diagnostic code at the same time. The study is approved by the regional ethical review board in Linko¨ping, Sweden (Dnr M214-07). The time period was chosen because the multidisciplinary team started in 2004 and remained a complete team until the spring of 2008. A nurse and a physiotherapist left the team at that time which limited the possibilities to offer patients a complete set of treatment options. Patients’ hearing loss was classified as a unilateral hearing loss when one of the ears was within normal limits, i.e. pure tone average (PTA) was 20 dB HL, and the PTA of the other ear was >20 dB HL. Bilateral hearing loss was defined as a hearing loss where PTA for both ears was >20 dB HL and could either be symmetric or asymmetric hearing loss. A hearing loss was classified as an asymmetric hearing loss if the difference between the PTA for both ears was larger than 15 dB HL. All classifications were made at the first visit by the ENT-doctors, based on patients’ audiograms. The investigators completed a form for each patient, covering background information, and audiograms taken at the
yearly check up. The background information contained data about the patient’s tinnitus, vertigo, hearing loss, diagnosis, further audiological examinations, treatment of tinnitus, heredity for tinnitus, concomitant diseases and medication. 2.1. Inclusion and exclusion criteria Medical records for all patients who had sought care for hearing problems during the study period and were diagnosed with sensorineural hearing loss were reviewed. Information from the ENT clinics’ medical records occasionally did not contain the Audiologist information obtained in the clinics, thus additional information was collected from the patients audiology case records. Patients between 20 and 80 years of age with tinnitus and a PTA ¨ stergo¨tland, lower than 70 dB HL were included in the study. In O patients with a PTA > 70 dB HL could be candidates for cochlea implants (CI) and were thereby not included in this study. Because of their profound hearing loss, these patients have severe problems. Therefore, there are normally other rehabilitation plans that are developed and handled by the CI-team. Patients were excluded from the analyses if they had a CI, middle ear disorders, or a hearing loss since birth/childhood. Multi-handicapped patients and those who did not speak fluent Swedish and had an interpreter at the ENT visit were also excluded. 2.2. Statistics Data were registered in Microsoft Office Excel. Distribution of patients between groups with two or more possible states was evaluated using Chi2 test, and in the 2 2 case Yates’ correction was used. Measurement variables were compared between groups with Student’s t-test. The level of significance was set at p < 0.05. 3. Results 3.1. Patient characteristics Medical record review of total 1672 patients with SNHL demonstrated that 1175 (70%) patients also had tinnitus (Fig. 1). An additional 446 patients (27%) were excluded because they did not experience tinnitus. Information about the frequency of occurrence of tinnitus was missing for 51 patients (3%), and those patients were thereby excluded from the analyses. Out of 1175 patients with both SNHL and tinnitus, 461 patients (39%) were excluded because they had a PTA > 70 dB HL or had a cochlear implantation, middle ear disorders, hearing loss since birth/ childhood, and/or could not speak fluent Swedish. The remaining 714 patients had SNHL with tinnitus, and fulfilled the specific inclusion criteria. The group consisted of more male patients (n = 388; 54%) than female (n = 326; 46%). The difference was significant (p = 0.02). The majority of patients were older than 50 years (Table 1). In patients with unilateral tinnitus, the prevalence of tinnitus in the left ear was higher (p < 0.001). In addition, the PTA for the left ear was significantly higher than for the right ear in male patients (p = 0.01) but not in females (p = 0.45). In all, 402 patients (56%) were diagnosed with bilateral SNHL, 151 (21%) with unilateral SNHL, and 161 (23%) with various diagnoses; 113 (16%) Mb Menie`re´, 32 (4%) sudden sensorineural hearing loss (SSHL), 9 (1%) noise-inducted SNHL, 5 (0.7%) presbyacusis, and 2 (0.2%) cochlear otosclerosis. There was an absence of information about patients’ vertigo in 47% of the medical records. The characteristics data for patients with unilateral vs. bilateral tinnitus are described in Table 1. There were more men than
R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
43
Medical record review N=1672 Paents diagnosed with “sensorineural hearing loss”
Included N=714
Excluded N=958
Paents with SNHL AND nnitus
SNHL AND unilateral nnitus n=358
SNHL AND bilateral nnitus n=356
PTA >70 dB HL n=461
SNHL without nnitus/periodic nnitus n=446
Medical records without informaon about nnitus n=51
Fig. 1. Study flowchart.
women among patients with bilateral tinnitus (p = 0.05). Out of 388 male patients; 65 had tinnitus on the right ear, 116 on the left ear and 207 patients had bilateral tinnitus. In female patients, 82 had tinnitus on the right ear, 95 on the left ear and 149 had bilateral tinnitus.
Patients with asymmetric hearing loss (61%) underwent retrocochlear examinations in a higher extent than patients with symmetric hearing loss (50%, p = 0.014). 105 patients underwent nystagmography and 54 patients had nystagmography in combination with MRI and/or ABR.
3.2. Examinations
3.3. Treatment
The PTA for the left ear compared to the right ear in patients with unilateral tinnitus showed no significant difference (p = 0.09). In patients with bilateral tinnitus, the left ear had higher PTA (p = 0.007). The results regarding the configuration of hearing loss revealed that 555 patients (78%) had symmetric and 159 (22%) asymmetric hearing loss. High frequency hearing loss was found to be more common (around 92%) in patients with symmetric hearing loss (Table 2). Retrocochlear examinations were done in 372 patients and MRI was the most common examination (Table 3). There was a significant difference between patients with unilateral tinnitus and bilateral tinnitus regarding use of the MRI examination (p = 0.001).
The results showed that 314 patients had hearing aids. There were no significant differences between male and female patients. Of those 400 without hearing aids, 220 patients had unilateral tinnitus and 180 bilateral tinnitus (Table 4). There were significantly more patients with bilateral tinnitus (49%) having hearing aids compared to patients with unilateral tinnitus (39%, p = 0.02). Two hundred and nineteen patients with a best ear PTA > 20 dB, did not have any hearing aid. Among those, 138 patients had unilateral tinnitus, and 81 patients bilateral tinnitus. The difference between these groups was significant (p < 0.001). For further analyses of how the Stepped Care model was used in the three largest diagnoses within SNHL, see Table 5. All patients were examined by an ENT doctor and 135 (20%) of them met an audiologist, with tinnitus training, for further treatment. Among
Table 1 Distribution of characteristics of patients with SNHL and tinnitus (n = 714). Bilateral tinnitus (n = 356) n (%)
Unilateral tinnitus (n = 358) n (%)
Total (n = 714) n (%)
149 (42) 28.4 15.9 31.1 16.6 207 (58) 30.7 16.9 31.1 16.6
177 (49) 24.7 15.2 26.7 14.5 181 (51) 27.2 16.1 29.4 15.8
326 (46) 26.7 16.6 29.1 15.8 388 (54) 28.9 16.4 30.2 16.0
<30 31–40 41–50 51–60 61–70 71–80
9 (2) 19 (5) 37 (10) 87 (25) 115 (33) 89 (25) 61.1 12.7
6 (2) 18 (5) 43 (12) 84 (23) 122 (34) 85 (24) 61.3 12.6
15 (2) 37 (5) 80 (11) 171 (24) 237 (34) 174 (24) 61.3 12.7
PTA (dB HL) (mean SD)
Right ear Left ear
29.6 14.9 31.3 15.1
26.4 17.6 28.3 16.7
28.0 14.8 29.5 10.6
Hearing aid
Bilateral Unilateral None
114 (32) 62 (17) 180 (51)
57 (16) 81 (23) 220 (61)
171(24) 143 (20) 400 (56)
Variables Gender and PTA (dB HL) (mean SD)
Female Right ear Left ear Male Right ear Left ear
Age group (year)
Age (mean SD)
R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
44
Table 2 Tinnitus and audiogram shape. Subjects with symmetrical hearing loss combined with unilateral or bilateral tinnitus (n = 555). Audiogram shape
n (%)
Low frequency loss Mid frequency loss High frequency loss Flat loss
4 9 509 33
4. Discussion Tinnitus is common in patients with SNHL [2,7]. Results of this study could verify that 70% of all patients who were diagnosed ¨ stergo¨tland County had tinnitus. Clinical informawith SNHL in O tion in patient’s records can be defined as ‘‘the commodity used to help make patient care decisions’’ [13]. Most of the information physicians obtain during a patient’s visit stay in physicians heads; ‘‘a constantly expanding and reinterpreted database’’ [14]. This could obviously interfere with an optimal care plan for the patients. After our first patient medical record review we found that there were notes in many patients’ records that the patients had stated to have constant tinnitus, but yet had not received a registered tinnitus diagnosis. In spite of this; they were of course included in our study. Our results showed that there was often lack of information not only about vertigo, tinnitus and heredity but also information about patients’ other diseases and general health. We have some hesitation concerning if all patients received an adequate diagnosis, given the very small sizes of some of the subgroups. It is possible that patients, who got a diagnosis of bilateral SNHL, could in fact have been classified as presbyacusis or noise-conducted hearing loss. In this study, the majority of patients were men (54%). This is not consistent with findings of Nondahl et al. [15]. They found the prevalence of tinnitus being higher among female patients. A possibility is that more male patients in our study have been working in noisy environments as we have observed that men in average had a little higher PTA values. Tinnitus is a common condition among older adults. Hoffman and Reed compared the prevalence of self-reported tinnitus from several large epidemiologic studies [16]. For those aged 50 years and older, the estimated prevalence of tinnitus ranged from 7.6% to 20.1%. In our study, we found that 79% of patients were older than 50 years, which has been reported in other studies [4]. Several reports as well as this study found unilateral tinnitus to be more common in the left ear [5,6], especially in male patients. Unfortunately, there is no explanation for how this phenomenon occurs. Tinnitus is often associated with some degree of hearing loss, usually high frequency hearing loss related to cochlear damage [6]. In the present study, high frequency hearing loss was also more represented. Unilateral SNHL associated with tinnitus and/or vertigo can be a sign of retrocochlear lesion, therefore these patients should be examined using retrocochlear examinations [17]. Of 159 patients with asymmetric SNHL, 61% were investigated by retrocochlear examinations. Of 357 patients with unilateral tinnitus, the corresponding figure was 64%. The extent of these examinations should ideally be 100%, since this is highly recommended in order
(0.7) (1.6) (91.7) (6.0)
Table 3 The most common retrocochlear examinations for patients with asymmetric- and symmetric hearing loss (n = 714). Examinations
MRI n (%)
ABR n (%)
Asymmetric SNHL and unilateral tinnitus (n = 103) Asymmetric SNHL and bilateral tinnitus (n = 56) Symmetric SNHL and unilateral tinnitus (n = 254) Symmetric SNHL and bilateral tinnitus (n = 301)
37 (36)
21 (20)
MRI/ABR n (%) 8 (8)
20 (36)
9 (16)
2 (4)
86 (34)
55 (22)
20 (8)
52 (17)
46 (15)
16 (5)
Table 4 Tinnitus and hearing aids (n = 714). n (%) Unilateral tinnitus (n = 358) With unilateral hearing aid With bilateral hearing aids Without hearing aid? PTA 20 dB HL PTA >20 dB HL
81 (23) 57 (16) 220 (61) 82 (37) 138(63)
Bilateral tinnitus (n = 356) With unilateral hearing aid With bilateral hearing aids Without hearing aid? PTA 20 dB HL PTA >20 dB HL
62 (17) 114 (32) 180 (51) 99 (55) 81(45)
those, 83 patients participated in the group information (61% of the patients who visited a tinnitus trained audiologist). Of all patients, 105 participated in the comprehensive group information on tinnitus, which is the step 2 in the Stepped Care model. The results show that after the step 2 there were 75 patients (71% of the participants in step 2) who needed further treatment in the third step. In total there were; 55 patients who visited a registered physical therapist (RPT), 35 a counselor and 31 a psychologist. CBT was used in 23 patients; 3 patients with Mb Me´nie`re, 13 with bilateral SNHL and 7 with unilateral SNHL.
Table 5 Distribution of characteristics of the three largest diagnoses (n = 714). Tinnitus
Bilateral Sensorineural Hearing loss (n = 402) Unilateral Sensorineural Hearing loss (n = 151) Mb Menie´re` (n = 113) a b c d e f
Hearing aid
The Stepped Care model a
RPT
c
Counselor
d
CBT
e
Unilat.
Bilat.
Unilat.
None
Group info
251
151
118
79
205
73
55
32
16
13
5
110
41
20
38
93
24
20
14
13
7
3
43
70
26
19
68
8
8
4
5
3
1
Comprehensive group information on tinnitus. Personal counseling by trained audiologist in tinnitus. Registered physical therapist. Counselor. Cognitive behavioral therapy. Psychologist consultation.
Audioloist
b
Bilat.
Psychologist
f
R. Zarenoe, T. Ledin / Auris Nasus Larynx 40 (2013) 41–45
to find all patients with e.g. a vestibular schwannoma. A recent study showed that 10% of patients with asymmetric SNHL are likely to have causative lesions found on MRI [18]. A majority of our patients (56%) did not have hearing aids, and this is similar to what has been reported in other studies [11]. It is likely that every patient with hearing loss was offered a hearing aid. There are many possible explanations for why the number of patients with hearing aids was so low. The stigma associated with hearing aid use, the limitations of amplification to remediate the fundamental difficulty of understanding speech in background noise, and also the economic issue [19]. In this study, a reason for patients not having hearing aids could be that most of them had a high frequency hearing loss and could, in quiet environments, handle a conversation in spite of their hearing impairment. The number of men who did not have any hearing aids was larger than in women, but no significant difference was found. Another hypothesis is that many patients might have difficulty accepting the fact that they need a hearing aid, especially men. Jerram and Purdy reported a greater use of hearing aids in patients with impaired hearing who accepted their hearing loss to a greater extent than in patients who denied their condition. In addition, patients who had higher pre-fitting expectations did not use their hearing aids to the same extent [20]. In the Stepped Care model, more expensive or time requiring treatments, which involve more resources (for example CBT), are reserved for patients who do not respond well to conventional treatments (for example hearing aid fitting). A multidisciplinary approach ‘‘provides a broad and detailed account of the recent developments in tinnitus research and clinical management’’ [1]. Our results show that the Stepped Care model could be effective for providing a better access for tinnitus-focused treatment in different levels and can make more resources available for patients with severe problems. An estimation from our data could be that 61% went from step 1 to step 2, whereas 71% continued from step 2 to step 3, giving a total number of 43% of all patients in step 1 who need the most resource consuming treatments. Thus patients in this way can reach their optimal level of care quicker no matter if they have unilateral or bilateral tinnitus. Patients, who were referred to the tinnitus team, could receive care adequately, by participating in the group information and getting in contact with other healthcare professions. A drawback in our study is that the number of patients who were included in the Stepped Care model was low. This could depend on lack of knowledge in ENT-doctors about how the Stepped Care model works. A more desirable model is of course that an audiologist, with tinnitus training, is the main first care giver for patients with tinnitus and hearing loss. Tinnitus sensation is for some of these patients associated with many adverse effects like depression, sleep disorders and even health problems. In addition to this cohort descriptive study, a study with focus on patients’ general health would be desirable. Such a study is ongoing. 5. Conclusion In a large cohort of patients with SNHL and tinnitus, we have investigated patterns of diagnostic procedures and treatments. The spite of hearing loss, only 44% of patients had hearing aids. In the designed Stepped Care program, only a few patients seem to need the more advanced treatments, like CBT. It was observed that
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medical record review often shows a lack of information about many background factors, such as; patients’ general health condition, which could be a quality factor that needs improvement. Conflict of interest None. The authors have no relevant financial interest in this article. Funding ¨ stergo¨tland, Gunnar Arnbrinks Stiftelse, The County Council of O and Linko¨pings La¨karesa¨llskap. Acknowledgment Financial support for this study has been received from the ¨ stergo¨tland, Gunnar Arnbrinks Stiftelse, and County Council of O Linko¨pings La¨karesa¨llskap. We thank all ENT-doctors, audiologists and administrative personnel who helped us gather our data. References [1] Andersson G, Baguley D, McKenna L. Tinnitus: A Multidisciplinary Approach. London: Whurr Publishers; 2005. [2] Sindhusake D, Mitchell P, Newall P, Golding M, Rochtchina E, Rubin G. Prevalence and characteristics of tinnitus in older adults: the blue mountains hearing study. Int J Audiol 2003;42:289–94. [3] Noell CA, Meyerhoff WL. Tinnitus: diagnosis and treatment of this elusive symptom. Geriatrics 2003;58:28–34. [4] Heller AJ. Classification and epidemiology of tinnitus. Otolaryngol Clin North Am 2003;36:239–48. [5] Meikle MB, Vernon J, Johnson RM. The perceived severity of tinnitus. Some observations concerning a large population of tinnitus clinic patients. Otolaryngol Head Neck Surg 1984;92:689–96. [6] Erlandsson SI, Hallberg LRM, Axelsson A. Psychological and audiological correlates of perceived tinnitus severity. Audiology 1992;31:168–79. [7] Sindhusake D, Golding M, Wigney D, Newall P, Jakobsen K, Mitchell P. Factors predicting severity of tinnitus: a population-based assessment. J Am Acad Audiol 2004;15:269–80. [8] Rupa V, Job A, George M, Rajshekhar V. Cost-effective initial screening for vestibular schwannoma: auditory brainstem response or magnetic resonance imaging? Otolaryngol Head Neck Surg 2003;128:823–8. [9] Teppo H, Heikkinen J, Laitakari K, Alho OP. Diagnostic delays in vestibular schwannoma. J Laryngol Otol 2009;123:289–93. [10] Parra LC, Pearlmutter BA. Illusory percepts from auditory adaptation. J Acoust Soc Am 2007;121:1632–41. [11] Aazh H, Moore BCJ, Roberts P. Patient-centered tinnitus management tool: a clinical audit. Am J Audiol 2009;18:7–12. [12] Sakata T, Esaki Y, Yamano T, Sueta N, Nakagawa T. A comparison between the feeling of ear fullness and tinnitus in acute sensorineural hearing loss. Int J Audiol 2008;47:134–40. [13] Wyatt J. Medical informatics, artefacts or science? Methods Inf Med 1996;35:197–200. [14] Tanenbaum SJ. Knowing and acting in medical practice: the epistemological politics of outcomes research. J Health Polit Policy Law 1994;19:27–44. [15] Nondahl DM, Cruickshanks KJ, Dalton DS, Klein BEK, Klein R, Schubert CR, et al. The impact of tinnitus quality of life in older adults. J Am Acad Audiol 2007;18:257–66. [16] Haffman H, Reed GW. Epidemiology of tinnitus. In: Snow JB, editor. Tinnitus: Theory and Management. Lewiston, NY: BC Decker Inc.; 2004. p. 16–41. [17] Turner RG, Shepard NT, Frazer GJ. Clinical performances of audiological and related diagnostic tests. Ear Hear 1984;5:187–94. [18] Cueva RA. Auditory brainstem response versus magnetic resonance imaging for the evaluation of asymmetric sensorineural hearing loss. Laryngoscope 2004;114:1686–92. [19] Kochkin S. Marketrak vii: obstacles to adult non-user adoption of hearing aids. Hear J 2007;60:24–51. [20] Jerram JCK, Purdy SC. Technology, expectations, and adjustment to hearing loss: predictors of hearing aid outcome. J Am Acad Audiol 2001;12:64–79.