Impact of Cochlear Implantation on Quality of Life and Mental Comorbidity in Patients Aged 80 Years

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1 The Laryngoscope VC 2016 The American Laryngological, Rhinological and Otological Society, Inc. Impact of Cochlear Implantation on Quality of Life and Mental Comorbidity in Patients Aged 80 Years Steffen Knopke, MD; Stefan Gr abel, Dr. rer. medic.; Ulrike F orster-ruhrmann, MD; Birgit Mazurek, MD, PhD; Agnieszka J. Szczepek, PhD; Heidi Olze, MD, PhD Objectives/Hypothesis: The objective of this study was to evaluate the outcome of cochlear implantation in elderly patients (80 or older) with progressive bilateral deafening. The measured outcomes included the quality of life, speech understanding, tinnitus distress, stress level, anxiety, and depressiveness. Study Design: Prospective cohort study. Methods: Seventeen 801 years (mean years) patients with progressive, postlingual, bilateral deafness were unilaterally implanted with multichannel cochlear implants. Data about their health-related quality of life (Nijmegen Cochlear Implantation Questionnaire) and their comorbidities were collected using specific validated questionnaires (tinnitus questionnaire, General Anxiety Disorder-7, Depression Scale, Perceived Stress Questionnaire). The speech understanding was assessed with the Freiburg Monosyllabic Test, whereas the subjective hearing was evaluated with the Oldenburg Inventory. Results: After the surgery, not only the subjective hearing but also health-related quality of life, speech understanding, and tinnitus distress of the implanted patients improved significantly. The perceived stress, general anxiety, and depressiveness were low or normal prior and after surgery. Conclusion: This study demonstrates a significant improvement in the quality of life and speech understanding in a group of elderly patients who underwent cochlear implantation. An additional positive indicator of a promising hearing rehabilitation was a significant improvement of the tinnitus distress. Perceived stress level, general anxiety, and the depressiveness of implanted patients were low and remained unaffected. Key Words: Implants, quality of life, language development. Level of Evidence: 4. Laryngoscope, 126: , 2016 From the Department of Otorhinolaryngology, Head and Neck Surgery, Campus Virchow-Klinikum (S.K., S.G., U.F-R., H.O.); the Department of Otorhinolaryngology, Head and Neck Surgery (H.O.); and the Tinnitus Center, Campus Charite Mitte (B.M., A.J.S.), Charite-University Medical Center Berlin, Berlin, Germany. Editor s Note: This Manuscript was accepted for publication February 29, Presented at the 86th Annual Meeting of the German Society for Otolaryngology, Berlin, Germany, May 13 May 16, The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Dr. Med Steffen Knopke, Department of Otorhinolaryngology, Head and Neck Surgery, Charite-University Medical Center Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, D Berlin, Germany. steffen.knopke@charite.de DOI: /lary INTRODUCTION In light of the sociodemographic changes, successful treatment of elderly patients becomes an increasingly relevant issue. Numerous studies supported the benefit of cochlear implants (CIs). 1,2 Subsequent to the initial research focus on audiological outcome, improving the quality of life (HRQoL) with CI has become recently gained importance. 3 8 Social isolation, affective disorders, and low quality of life have been described as consequences of a severe loss of hearing. 8,9 In a large study of 1,984 elderly patients, Lin et al. 10 report an aggravation of cognitive deficits by the loss of hearing. The same authors communicate positive effect of hearing rehabilitation. Consequently, benefit analyses of cochlear implantation in elderly patients are medically, socially, and socioeconomically relevant. However, only few studies investigated patients who were 70 years or older and even fewer patients who would be 80 years or older. 11,12 In our previous work, we have demonstrated the positive effect of CI in a group of patients who were 70 years or older. 5 In that article, in addition to significant improvement of the audiological parameters, we demonstrated a decline of tinnitus and stress level and an improvement of the HRQoL. In contrast to the elderly hearing-impaired subjects, 13 our patients had an improved well-being and self-esteem and increased their everyday life activities following the cochlear implantation. To our best knowledge, to date there are no studies focusing on the complex comorbidities of patients of 80 years or older Hence, the objective of the present study was to perform a complex evaluation of the CI treatment outcome in a group of patients who were 80 years or older. All patients were diagnosed with progressive bilateral hearing impairment. In addition to audiometry, the outcome measures included HRQoL, speech understanding, scoring of tinnitus distress, perceived stress, depressiveness, and general anxiety. MATERIALS AND METHODS In the period from 2011 to 2013, 17 patients with bilateral postlingual progressive deafening were prospectively examined. 2811

2 Their average age was years, the median being 81.5 years. The duration of deafening at the time of implantation was years. In this study, we used the term duration of deafening to refer to the date when the patients first recognized their own complete hearing loss. The study took place in the Department of Otorhinolaryngology, Head and Neck Surgery Charite University Hospital Berlin, Germany. The study has been approved by a local ethics committee. Patients included in this study had a speech understanding score of 40% in the Freiburg Monosyllabic Test in quiet and with hearing aid. Twelve patients were implanted with MED-El systems (9x Concerto, 3x Sonata, MED-El, Austria) and five patients with Cochlear systems (4x Freedom, 1x CI422, Cochlear, Australia). The postimplantation observation interval was 6 months. The group was investigated pre- and postoperatively using audiological and psychometric tests. Health-Related Quality of Life: Nijmegen Cochlear Implantation Questionnaire The Nijmegen Cochlear Implantation Questionnaire (NCIQ) is a validated measuring tool designed to determine the HRQoL of CI patients. The three main categories physical, psychological, and social derive from six subcategories. The score ranges from 0 (very bad) to 100 (optimal). 14 Audiometric Data: Speech Understanding The Freiburg Monosyllabic Test was used to determine the preoperative speech understanding in silence at 65 db sound pressure level (SPL) with optimized hearing aid. After CI, the Freiburg Monosyllabic Test in quiet at 70 db SPL was done again as well as the Oldenburg Sentence Test at 65 db. Subjective Audiological Assessment: Oldenburg Inventory Data were collected pre- and postoperatively about the subjective hearing with the Oldenburg Inventory (OI). The OI additionally includes a total score in three categories: hearing in quiet, hearing with background noise, and localization. The 12 closed questions about everyday situations were marked with points from 1 to 5. The higher the score, the better the subjective hearing. 15 Fig. 1. Health-related quality of life: The NCIQ total value and the subdomains NCIQ 1 6 preoperative (light) and postoperative (dark). Physical subdomain: NCIQ1 5 basic sound perception; NCIQ2 5 advanced sound perception; NCIQ3 5 speech production. Psychological subdomain: NCIQ4 5 self-esteem. Social subdomain: NCIQ5 5 activity; NCIQ6 5 social interactions. **P < CI 5 cochlear implant; NCIQ 5 Nijmegen Cochlear Implantation Questionnaire. Comorbidities Tinnitus Distress: G obel and Hiller Tinnitus Questionnaire. The tinnitus level can be determined with the Goebel and Hiller Tinnitus Questionnaire (TQ). 16 Collected data represent six subdomains: emotional distress, cognitive distress, intrusiveness, auditory perceptual difficulties, sleeping disturbances, and somatic complaints. The mean value is used to determine tinnitus grade: light (0 30 points), average (31 46 points), high (47 59 points), and very high (60 84 points). In addition, separation into compensated ( 46 points) and decompensated (47 84 points) tinnitus can be done based on the total score. The test retest reliability is 0.94 for the total value and between 0.86 and 0.92 for the subscales. Cronbach s a is 0.94 for the total value of the TQ and between 0.74 and 0.92 for the subscales. 17 Stress Level: Perceived Stress Questionnaire. The Perceived Stress Questionnaire (PSQ) is used to collect information about the individual subjective stress level and the corresponding emotional response. It contains 30 questions. The questionnaire has been designed by Levenstein et al. 18 and validated for the German-speaking subjects. 19 The limit value for a low stress level is between The total value for healthy adults is The internal consistence of the total value of the German version is 0.85 (Cronbach s a) and the split-half reliability is General Anxiety Disorder-7. The General Anxiety Disorder-7 Questionnaire (GAD-7) is a self-rating tool used to identify the level of generalized anxiety in a patient and to determine the severity of the related symptoms. The total score can be read in four categories of level: minimal (0 4 points), light (5 9 points), average (10 14 points), and heavy (15 21 points). The internal consistence is a Cronbach s a L ow et al. indicated norm values of for women and for men. 21 Depressiveness: Depression Scale. The Depression Scale (ADS-L) has 20 items and is used for the self-rating of impairments by depression symptoms in the last weeks. The analysis is based on gender-specific cutoff values. The internal consistence (Cronbach s a) ranges from 0.89 to Statistics The difference between the parameters before and after CI were computed with the nonparametric Wilcoxon-Test for paired samples. The correlation analysis was carried out with Spearman s rank-correlation test. The results are shown in the text as mean 6 standard deviation. The level of significance was 5%. The statistical analysis was performed with Statistica 7.1 (StatSoft, Tulsa, OK). RESULTS HRQoL The score of HRQoL increased significantly following the cochlear implantation, as measured with the NCIQ. The total score of NCIQ increased from preoperative to postoperative (P < 0.01). The subscales physical NCIQ1 (basic sound perception) and NCIQ2 (advanced sound perception) of the 2812

3 Fig. 2. Scattergram of pretreatment hearing results in studied patients according to the American Academy of Otolaryngology Head and Neck Surgery recommendation. Pure-tone averages are represented on the y-axis and word recognition scores (Freiburg Monosyllabic Test, 65 db sound pressure level) are represented on the x-axis. Each number represents the number of patients. psychological NCIQ4 (self-esteem), as well as the social NCIQ5 (activity) and NCIQ6 (social interactions), have improved significantly (P < 0.01) (Fig. 1). The subdomain NCIQ3 (speech production) increased with CI; however, it did not improve significantly with relatively high output. The daily duration of CI-wearing was hours. Speech Understanding Speech understanding improved significantly in the operated ear following the CI, as per the Freiburg Monosyllabic Test. The score of % before surgery (Fig. 2) increased to % after surgery. In the Oldenburg Sentence Test, the level of speech understanding was db S/N (signal-noise difference). Subjective Audiological Assessment. Subjective rating of hearing improved significantly following implantation. The total value of the OI (before ; after ) improved in the three subcategories hearing in quiet (before ; after ), hearing with background noise (before ; after ), and localization (before ; after ) (P < 0.01) (Fig. 3). Fig. 3. Subjective audiological self-rating: Oldenburg Inventory score preoperative (light) and postoperative (dark). Subdomain: noise 5 hearing with background noise, localization. ** P < CI 5 cochlear implant. There was a noticeable reduction of tinnitus distress in cases of preoperative high or very high TQ scores. Two patients had decompensated tinnitus prior to implantation. Their distress decreased after cochlear implantation from level 4 to level 3 in one case and level 2 in other case. Perceived Stress Level. Patients aged 80 years or older scored preoperatively with a PSQ total value of and postoperatively The scores remained constant before and after CI within the range of normal values ( ), and the difference preand postimplantation was not significant (Fig. 5). General Anxiety. The GAD-7 demonstrated no significant score reduction following the cochlear implantation (before ; after ). The postoperative Comorbidities Tinnitus Distress. Twelve of 17 analyzed patients (70.6%) reported chronic tinnitus before CI. Five patients (29.4%) reported no postoperative tinnitus; nine patients (66.7%) reported improvement; and three patients (33.3%) could notice no change after CI. A worsening of tinnitus distress was not reported. The mean value of TQ score before implantation was and decreased significantly (P < 0.05) to after implantation (Fig. 4). There was no correlation between tinnitus distress and age of the patients. Fig. 4. Tinnitus distress. G obel and Hiller Tinnitus Questionnaire total value and subdomains preoperative (light) and postoperative (dark). Subdomain: E 5 emotional distress; C 5 cognitive distress; I 5 intrusiveness; A 5 auditory perceptual difficulties; SI 5 sleeping disturbances; SO 5 somatic complaints; total 5 total value. *P < CI 5 cochlear implant. 2813

4 Fig. 5. Stress level: The PSQ total value and subdomains (worries, tension, joy, demands) preoperative (light) and postoperative (dark). No significant difference. CI 5 cochlear implant; PSQ 5 Perceived Stress Questionnaire. score was within normal range. There was no significant correlation between patient age and the general anxiety. Depressiveness. Screening for depressive symptoms with ADS-L revealed no significant changes in the before/after CI comparison. The mean values before and after CI were low (before: ; after: ). Three patients had elevated ADS-L score before CI, indicative of depressive disorder (total value > 23). Two patients had elevated ADS-L score after CI. Significant correlation between patient age and depressiveness could not be found. DISCUSSION Improvement of hearing is the main goal of cochlear implantation. However, reinstating the hearing in the impaired patients also means improvement of the quality of life, tinnitus reduction, and positive impact on mental comorbid conditions. Data regarding elderly patients who are 80 or older are scarce. Nevertheless, due to the aging of our society, precisely this population grows and is in focus of contemporary medical and psychosocial studies. Studies regarding cochlear implantation, tinnitus distress, and mental comorbidities in this particular age group have not been yet performed. In addition to the audiological benefit, our present study provides the evidence to support the positive impact of CIs on the quality of life, tinnitus distress, and mental comorbidities. Health-Related Quality of Life There was a noticeable improvement of the HRQoL score in our sample. We have previously studied patients under and over 70 years of age. 5 The HRQoL increased in the group older than 70 years more than in the younger one; however, both groups increased significant after CI. Patients in the age group between 50 and 80 years significantly improve their quality of life following CI In addition, significant correlation between the audiological gain and the HRQoL has been found in that group. The quality of life measured with the Glasgow Benefit Inventory in a group of CI patients who were 70 years or older improved significantly following implantation (total score , general score , physical score , social score ). 23 In addition, the authors describe a positive correlation between the HRQoL and the age of patients. A retrospective postoperative observation study with patients who were 80 years or older reported a noticeable improvement of HRQoL measured with the Glasgow Benefit Inventory (total score , general subscore , physical subscore , ). 11 The post-ci improvement in HRQoL associates with the improvement of speech understanding. The consequence of a permanent hearing impairment is a combination of cognitive deficiency and social isolation. A worsening of cognitive performance and syndromes of dementia, as well as a reduction of the physical ability, are possible consequences. 24 For this reason, sufficient hearing rehabilitation including CI is required regardless of the patients age, which is no contraindication for CI. 25 Audiological Outcome. We found a significant auditory improvement in our sample. Although two retrospective works indicate positive results in this regard, similar data about this age group are not available. A retrospective study with patients 79 years or older demonstrated significant improvement in the audiological performance (postoperative pure tone average ; postoperative speech understanding score: Hearing in Noise Test (HINT) , City University of New York sentence test (CUNY) ). 26 In another retrospective work, a significant increase of speech understanding with CI was noted (speech understanding score: HINT , Multimedia Auditory Test (MAT) ). 11 A lower gain of speech understanding by elderly patients (60 years or older) has been documented in the literature. 23,27 29 An audiological deficit found in the elderly patients 6 months after cochlear implantation is likely a result of inadequate time of the learning process following implantation. 30 According to Chan et al., 29 audiological deficits cannot be found after a learning period of 12 month or more. It is likely that deficits in the central auditory system in the area of the temporal region may be the cause. 30 A multivariate regression analysis of a population older than 65 years revealed no strong link of the audiological outcome with the duration of implantation. 31 Rather, the duration of hearing impairment has been suggested as a factor with a predictive relevance for the degree of speech understanding after CI surgery. In our study, a long-term follow-up confirming the requirement of timely implantation is not yet available, and the present analyses have not found associations seen by others in younger patients.

5 Comorbidities Tinnitus Distress. High prevalence of tinnitus in patients with auditory disorders is well-known. Baguley et al. 32 report in a systematic review of 1,104 CI candidates a prevalence of tinnitus between 67% to 100% with an average of 80%. Additionally, the authors found a reduction of tinnitus ranging from 36% to 83% in the unilaterally CI-implanted patients. Our present study demonstrated that in a group of patients who were 80 years or older, a reduction of tinnitus occurs in 67% of the cases, with 70.6% of the group having tinnitus before cochlear implantation. Our data are similar to those obtained by Baguley et al. 32 about the general tinnitus prevalence in all CI users, although this kind of data has been available only on younger CI users so far. We have previously demonstrated that the CI treatment of patients with a severe hearing impairment results in a subsequent reduction of tinnitus distress. 5,9 Quaranta et al. 33 report the reduction of tinnitus on the contralateral side after unilateral CI. Presumably, neural plasticity leading to reorganization of the central auditory pathway and of the central auditory cortex may be responsible for such phenomena. Evidence exists that during aging not only the spiral ganglion of the peripheral auditory system but also the central auditory structures may degenerate. 34,35 The presumably worse rehabilitation performance of elderly patients following cochlear implantation seems to be resulting from their limited memorizing and learning abilities. 28,36,37 The study results about patients aged 80 years or older explicitly show a similar tinnitus reduction. Cognitive performance seems to be more influential than the patients age as such. 38 Rather, tinnitus in cases of auditory disorders is a limiting cofactor. 39 Psychopathological Comorbidities Stress Level. The post-ci implantation stress reduction has been previously observed in younger patients. 4,9,40,41 However, as opposed to younger individuals, the persons 80 and older had low stress index at the onset and at the end of our study, and no additional decrease was seen. In our previous studies, we have also seen low stress index in patients who were 70 years or older. 4 It is therefore tempting to speculate that during the retirement the lack of stressors resulting from professional and/or private life lowers the overall perception of stress. General Anxiety. Despite heavy auditory impairment of the target group, there were no differences between GAD-7 scores pre- and post-ci implantation, indicating affective stability of the patients our study sample. Zirke et al. 16 report high GAD-7 scores in patients with chronic tinnitus and auditory disorders. Likewise, Andersson et al. 39 reported a link between psychopathological comorbidities in patients with auditory handicaps. Moreover, a significant reduction of anxiety after CI has been demonstrated for mixed-age populations. 4,5,40,42 Depressiveness. The occurrence of affective imbalance such as depression resulting from an auditory disorder is well-known. Depressive symptoms cause social isolation, lower self-esteem, and cognitive deficits. 43,44 Cochlear implant was shown to have a positive impact on depression scores. 45 We have previously demonstrated a link between depression symptoms and different comorbidities in patients with auditory disorders. 9,16 Andersson et al. 39 found evidence for an association between auditory disorders, affective symptoms, and the HRQoL. Interestingly, in our present study, despite the high grade of hearing impairment, there were no depressive symptoms in the sample studied. In contrary, the depressive symptom scores were similar to those of the control subjects. There was no correlation between the NCIQ and ADS-L. Thus, the significant HRQoL improvement in the study population of patients aged 80 years or older cannot be attributed to the improvement of depressive symptoms. CONCLUSION Our study provides evidence to support the benefits of CI for patients who are 80 years or older. In addition to a significant increase in the health-related quality of life the speech understanding improves whereas the tinnitus distress decreases following the CI implantation. Thus, we have confirmed the feasibility of cochlear implantation for the age group 80 years or older. In the group of patients studied, the mental conditions such as perceived stress, anxiety, and depressiveness were consistently present on a low level. Cochlear implant has not influenced the mental status of elderly patients. Regaining the ability to communicate is a priority of cochlear implantation. Cognitive deficits resulting from social isolation due to auditory disorders must be avoided. The impact of possibly existing cognitive restrictions on the rehabilitation s success or aptitude of elderly CI candidates will be, not least for predictive reasons, a relevant question for future research. BIBLIOGRAPHY 1. Blamey PJ, Maat B, Başkent D, et al. A retrospective multicenter study comparing speech perception outcomes for bilateral implantation and bimodal rehabilitation. Ear Hear 2015;36: van Zon A, Peters JPM, Stegeman I, Smit AL, Grolman W. Cochlear implantation for patients with single-sided deafness or asymmetrical hearing loss: a systematic review of the evidence. Otol Neurotol 2015;36: Rumeau C, Frere J, Montaut-Verient B, Lion A, Gauchard G, Parietti- Winkler C. 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