Impact of Cochlear Implantation on Neurocognitive Subdomains in Adult Cochlear Implant Recipients

A Scoping Review and Meta-Analysis of the Relations Between Cognition and Cochlear Implant Outcomes and the Effect of Quiet Versus Noise Testing Conditions

OBJECTIVES

Evidence continues to emerge of associations between cochlear implant (CI) outcomes and cognitive functions in postlingually deafened adults. While there are multiple factors that appear to affect these associations, the impact of speech recognition background testing conditions (i.e., in quiet versus noise) has not been systematically explored. The two aims of this study were to (1) identify associations between speech recognition following cochlear implantation and performance on cognitive tasks, and to (2) investigate the impact of speech testing in quiet versus noise on these associations. Ultimately, we want to understand the conditions that impact this complex relationship between CI outcomes and cognition.

DESIGN

A scoping review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed on published literature evaluating the relation between outcomes of cochlear implantation and cognition. The current review evaluates 39 papers that reported associations between over 30 cognitive assessments and speech recognition tests in adult patients with CIs. Six cognitive domains were evaluated: Global Cognition, Inhibition-Concentration, Memory and Learning, Controlled Fluency, Verbal Fluency, and Visuospatial Organization. Meta-analysis was conducted on three cognitive assessments among 12 studies to evaluate relations with speech recognition outcomes. Subgroup analyses were performed to identify whether speech recognition testing in quiet versus in background noise impacted its association with cognitive performance.

RESULTS

Significant associations between cognition and speech recognition in a background of quiet or noise were found in 69% of studies. Tests of Global Cognition and Inhibition-Concentration skills resulted in the highest overall frequency of significant associations with speech recognition (45% and 57%, respectively). Despite the modest proportion of significant associations reported, pooling effect sizes across samples through meta-analysis revealed a moderate positive correlation between tests of Global Cognition (r = +0.37, p < 0.01) as well as Verbal Fluency (r = +0.44, p < 0.01) and postoperative speech recognition skills. Tests of Memory and Learning are most frequently utilized in the setting of CI (in 26 of 39 included studies), yet meta-analysis revealed nonsignificant associations with speech recognition performance in a background of quiet (r = +0.30, p = 0.18), and noise (r = -0.06, p = 0.78).

CONCLUSIONS

Background conditions of speech recognition testing may influence the relation between speech recognition outcomes and cognition. The magnitude of this effect of testing conditions on this relationship appears to vary depending on the cognitive construct being assessed. Overall, Global Cognition and Inhibition-Concentration skills are potentially useful in explaining speech recognition skills following cochlear implantation. Future work should continue to evaluate these relations to appropriately unify cognitive testing opportunities in the setting of cochlear implantation.

Sustained Cognitive Improvement in Patients over 65 Two Years after Cochlear Implantation

This study aimed to evaluate the long-term benefits of cochlear implantation (CI) on cognitive performance, speech perception, and psychological status in post-lingually deafened patients older than 65 (n = 33). Patients were consecutively enrolled in this prospective study and assessed before, one year after, and two years after CI for speech perception, depressive symptoms, perceived stress, and working memory and processing speed. The Wechsler Adult Intelligence Scale (WAIS) was used for the latter. Thirty-three patients (fourteen men and nineteen women) were included. The scores indicating "hearing in quiet" and "hearing with background noise" improved significantly one year after CI and remained so two years after CI. The sound localization scores improved two years after CI. The depressive symptoms and perceived stress scores were low at the study's onset and remained unchanged. Working memory improved significantly two years after CI, while processing speed improved significantly one year after CI and was maintained after that. The improvement in working memory and processing speed two years after CI suggests there is a sustained positive effect of auditory rehabilitation with CI on cognitive abilities.

A Five-Decade Text Mining Analysis of Cochlear Implant Research: Where We Started and Where We Are Heading

Background and Objectives: Since its invention in the 1970s, the cochlear implant (CI) has been substantially developed. We aimed to assess the trends in the published literature to characterize CI. Materials and Methods: We queried PubMed for all CI-related entries published during 1970-2022. The following data were extracted: year of publication, publishing journal, title, keywords, and abstract text. Search terms belonged to the patient's age group, etiology for hearing loss, indications for CI, and surgical methodological advancement. Annual trends of publications were plotted. The slopes of publication trends were calculated by fitting regression lines to the yearly number of publications. Results: Overall, 19,428 CIs articles were identified. Pediatric-related CI was the most dominant sub-population among the age groups, with the highest rate and slope during the years (slope 5.2 ± 0.3, p < 0.001), while elderly-related CIs had significantly fewer publications. Entries concerning hearing preservation showed the sharpest rise among the methods, from no entries in 1980 to 46 entries in 2021 (slope 1.7 ± 0.2, p < 0.001). Entries concerning robotic surgery emerged in 2000, with a sharp increase in recent years (slope 0.5 ± 0.1, p < 0.001). Drug-eluting electrodes and CI under local-anesthesia have been reported only in the past five years, with a gradual rise. Conclusions: Publications regarding CI among pediatrics outnumbered all other indications, supporting the rising, pivotal role of CI in the rehabilitation of children with sensorineural hearing loss. Hearing-preservation publications have recently rapidly risen, identified as the primary trend of the current era, followed by a sharp rise of robotic surgery that is evolving and could define the next revolution.

Emerging Relations among Cognitive Constructs and Cochlear Implant Outcomes: A Systematic Review and Meta-Analysis

OBJECTIVE

Hearing loss has a detrimental impact on cognitive function. However, there is a lack of consensus on the impact of cochlear implants on cognition. This review systematically evaluates whether cochlear implants in adult patients lead to cognitive improvements and investigates the relations of cognition with speech recognition outcomes.

DATA SOURCES

A literature review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies evaluating cognition and cochlear implant outcomes in postlingual, adult patients from January 1996 to December 2021 were included. Of 2510 total references, 52 studies were included in qualitative analysis and 11 in meta-analyses.

REVIEW METHODS

Proportions were extracted from studies of (1) the significant impacts of cochlear implantation on 6 cognitive domains and (2) associations between cognition and speech recognition outcomes. Meta-analyses were performed using random effects models on mean differences between pre- and postoperative performance on 4 cognitive assessments.

RESULTS

Only half of the outcomes reported suggested cochlear implantation had a significant impact on cognition (50.8%), with the highest proportion in assessments of memory & learning and inhibition-concentration. Meta-analyses revealed significant improvements in global cognition and inhibition-concentration. Finally, 40.4% of associations between cognition and speech recognition outcomes were significant.

CONCLUSION

Findings relating to cochlear implantation and cognition vary depending on the cognitive domain assessed and the study goal. Nonetheless, assessments of memory & learning, global cognition, and inhibition-concentration may represent tools to assess cognitive benefit after implantation and help explain variability in speech recognition outcomes. Enhanced selectivity in assessments of cognition is needed for clinical applicability.

Longitudinal trajectories of memory among middle-aged and older people with hearing loss: the influence of cochlear implant use on cognitive functioning

Introduction

Cochlear implants (CI) are the gold standard intervention for severe to profound hearing loss, a known modifiable risk factor for dementia. However, it remains unknown whether CI use might prevent the age-related cognitive decline. Recent studies are encouraging but are limited, mainly by short follow-up periods and, for ethical reasons, lack of appropriate control groups. Further, as age-related cognitive decline is multifaceted and not linear, other statistical approaches have to be evaluated.

Materials and methods

Immediate and delayed recall as measures of cognitive function were assessed in 75 newly implanted CI users (mean age 65.41 years ± 9.19) for up to 5 years (mean 4.5 ± 0.5) of CI use and compared to 8,077 subjects of the same age range from two longitudinal cohort studies, the Health and Retirement Study (HRS) and the English Longitudinal Study of Aging (ELSA). Linear and quadratic changes in cognitive trajectories were analyzed in detail using mixed growth models, considering possible confounders.

Results

For CI users, the linear time slope showed a significant improvement in the specific domains (recall and delayed recall) over time. The quadratic time slope clearly indicated that the predicted change after CI provision followed an inverted U-shape with a predicted decline 2 years after CI provision. In the hearing-impaired group, a significant decline over time was found, with steeper declines early on and the tendency to flatten out in the follow-up.

Conclusion

Cochlear implant use seems to boost cognitive trajectories in the first years after implantation. However, long-term prevention of dementia seems to need far more than restoration of hearing loss.

Effects of cochlear implantation on cognitive decline in older adults: A systematic review and meta-analysis

Background

Hearing loss has been reported as the most significant modifiable risk factor for dementia, but it is still unknown whether auditory rehabilitation can practically prevent cognitive decline. We aim to systematically analyze the longitudinal effects of auditory rehabilitation via cochlear implants (CIs).

Methods

In this systematic review and meta-analysis, we searched relevant literature published from January 1, 2000 to April 30, 2022, using electronic databases, and selected studies in which CIs were performed mainly on older adults and follow-up assessments were conducted in both domains: speech perception and cognitive function. A random-effects meta-analysis was conducted for each domain and for each timepoint comparison (pre-CI vs. six months post-CI; six months post-CI vs. 12 months post-CI; pre-CI vs. 12 months post-CI), and heterogeneity was assessed using Cochran's Q test.

Findings

Of the 1918 retrieved articles, 20 research papers (648 CI subjects) were included. The results demonstrated that speech perception was rapidly enhanced after CI, whereas cognitive function had different speeds of improvement for different subtypes: executive function steadily improved significantly up to 12 months post-CI (g = 0.281, p < 0.001; g = 0.115, p = 0.003; g = 0.260, p < 0.001 in the order of timepoint comparison); verbal memory was significantly enhanced at six months post-CI and was maintained until 12 months post-CI (g = 0.296, p = 0.002; g = 0.095, p = 0.427; g = 0.401, p < 0.001); non-verbal memory showed no considerable progress at six months post-CI, but significant improvement at 12 months post-CI (g = -0.053, p = 0.723; g = 0.112, p = 0.089; g = 0.214, p = 0.023).

Interpretation

The outcomes demonstrate that auditory rehabilitation via CIs could have a long-term positive impact on cognitive abilities. Given that older adults' cognitive abilities are on the trajectory of progressive decline with age, these results highlight the need to increase the adoption of CIs among this population.

Cochlear implants: the effects of age on outcomes

INTRODUCTION

Cochlear implants (CIs) provide access to sound for children and adults who do not receive adequate benefit from hearing aids. Age at implantation is known to affect outcomes across the lifespan.

AREAS COVERED

The effects of age on CI outcomes are examined for infants, children, adolescents, and older adults. A variety of outcome measures are considered, including speech perception, language, cognition, and quality of life measures.

EXPERT OPINION/COMMENTARY

For those meeting candidacy criteria, CIs are beneficial at any age. In general, younger age is related to greater benefit when considering pre-lingual deafness. Other factors such as additional disabilities, may mitigate this effect. Post-lingually deafened adults demonstrate similar benefit regardless of age, though the oldest individuals (80+) may see smaller degrees of improvement from preoperative scores. Benefit can be measured in many ways, and the areas of greatest benefit may vary based on age: young children appear to see the greatest effects of age at implantation on language measures, whereas scores on cognitive measures appear to be most impacted for the oldest population. Future research should consider implantation at extreme ages (5-9 months or > 90 years), unconventional measures of CI benefit including qualitative assessments, and longitudinal designs.

Evaluation of the Cognitive Function of Adults with Severe Hearing Loss Pre- and Post-Cochlear Implantation Using Verbal Fluency Testing

Hearing loss is a major public health problem with significant evidence correlating it with cognitive performance. Verbal fluency tests are commonly used to assess lexical access. They provide a great deal of information about a subject's cognitive function. The aim of our study was to evaluate phonemic and semantic lexical access abilities in adults with bilateral severe to profound hearing loss and then to re-evaluate a cohort after cochlear implantation. 103 adult subjects underwent phonemic and semantic fluency tests during a cochlear implant candidacy evaluation. Of the total 103 subjects, 43 subjects underwent the same tests at 3 months post-implantation. Our results showed superior performance in phonemic fluency compared to semantic fluency in subjects prior to implantation. Phonemic fluency was positively correlated with semantic fluency. Similarly, individuals with congenital deafness had better semantic lexical access than individuals with acquired deafness. Results at 3 months post-implantation showed an improvement in phonemic fluency. No correlation was found between the evolution of pre- and post-implant fluency and the auditory gain of the cochlear implant, and we found no significant difference between congenital and acquired deafness. Our study shows an improvement in global cognitive function after cochlear implantation without differentiation of the phonemic-semantic pathway.

Listening with an Ageing Brain - a Cognitive Challenge

Hearing impairment has been recently identified as a major modifiable risk factor for cognitive decline in later life and has been becoming of increasing scientific interest. Sensory and cognitive decline are connected by complex bottom-up and top-down processes, a sharp distinction between sensation, perception, and cognition is impossible. This review provides a comprehensive overview on the effects of healthy and pathological aging on auditory as well as cognitive functioning on speech perception and comprehension, as well as specific auditory deficits in the 2 most common neurodegenerative diseases in old age: Alzheimer disease and Parkinson syndrome. Hypotheses linking hearing loss to cognitive decline are discussed, and current knowledge on the effect of hearing rehabilitation on cognitive functioning is presented. This article provides an overview of the complex relationship between hearing and cognition in old age.

Update on surgical and nonsurgical treatment options for age-related hearing loss

BACKGROUND

Age-related hearing loss (ARHL) is one of the most common chronic conditions that impacts on everyday life far beyonds speech understanding. Chronic hearing loss has been associated with social isolation, depression, and cognitive decline. Early diagnosis and appropriate treatment are recommended.

OBJECTIVE

To give an overview of surgical and non-surgical treatment options for ARHL and the gap between the high prevalence of ARHL and its inadequate treatment to date.

MATERIAL AND METHODS

A selective literature search was carried out in PubMed.

RESULTS

In case of mild to moderate hearing loss, provision of air conduction hearing aids is still the method of choice as it leads to a large benefit in speech understanding and hearing-specific quality of life, and to a slight improvement in overall quality of life. Implantable middle ear systems are used for the treatment of special types of hearing impairment. In case of severe to profound hearing loss, cochlear implantation should be considered; however, only a small number of older people with hearing loss are supplied with hearing aids or cochlear implants despite the well-known benefits of both. This also applies to high-income countries where the costs are covered by health insurance funds.

CONCLUSION

Considering the low rate of properly treated people with hearing loss, large-scale screening programs, including better counselling of older people, should be developed.

Neuropsychological Functions and Audiological Findings in Elderly Cochlear Implant Users: The Role of Attention in Postoperative Performance

Objectives: The present study aimed to investigate in a group of elderly CI users working memory and attention, conventionally considered as predictors of better CI performance and to try to disentangle the effects of these cognitive domains on speech perception, finding potential markers of cognitive decline related to audiometric findings. Methods Thirty postlingually deafened CI users aged >60 underwent an audiological evaluation followed by a cognitive assessment of attention and verbal working memory. A correlation analysis was performed to evaluate the associations between cognitive variables while a simple regression investigated the relationships between cognitive and audiological variables. Comparative analysis was performed to compare variables on the basis of subjects’ attention performance. Results: Attention was found to play a significant role in sound field and speech perception. Univariate analysis found a significant difference between poor and high attention performers, while regression analysis showed that attention significantly predicted recognition of words presented at Signal/Noise +10. Further, the high attention performers showed significantly higher scores than low attentional performers for all working memory tasks. Conclusion: Overall findings confirmed that a better cognitive performance may positively contribute to better speech perception outcomes, especially in complex listening situations. WM may play a crucial role in storage and processing of auditory-verbal stimuli and a robust attention may lead to better performance for speech perception in noise. Implementation of cognitive training in auditory rehabilitation of CI users should be investigated in order to improve cognitive and audiological performance in elderly CI users.

Preoperative Reading Efficiency as a Predictor of Adult Cochlear Implant Outcomes

HYPOTHESES

1) Scores of reading efficiency (the Test of Word Reading Efficiency, second edition) obtained in adults before cochlear implant surgery will be predictive of speech recognition outcomes 6 months after surgery; and 2) Cochlear implantation will lead to improvements in language processing as measured through reading efficiency from preimplantation to postimplantation.

BACKGROUND

Adult cochlear implant (CI) users display remarkable variability in speech recognition outcomes. "Top-down" processing-the use of cognitive resources to make sense of degraded speech-contributes to speech recognition abilities in CI users. One area that has received little attention is the efficiency of lexical and phonological processing. In this study, a visual measure of word and nonword reading efficiency-relying on lexical and phonological processing, respectively-was investigated for its ability to predict CI speech recognition outcomes, as well as to identify any improvements after implantation.

METHODS

Twenty-four postlingually deaf adult CI candidates were tested on the Test of Word Reading Efficiency, Second Edition preoperatively and again 6 months post-CI. Six-month post-CI speech recognition measures were also assessed across a battery of word and sentence recognition.

RESULTS

Preoperative nonword reading scores were moderately predictive of sentence recognition outcomes, but real word reading scores were not; word recognition scores were not predicted by either. No 6-month post-CI improvement was demonstrated in either word or nonword reading efficiency.

CONCLUSION

Phonological processing as measured by the Test of Word Reading Efficiency, Second Edition nonword reading predicts to a moderate degree 6-month sentence recognition outcomes in adult CI users. Reading efficiency did not improve after implantation, although this could be because of the relatively short duration of CI use.

Can cochlear implantation prevent cognitive decline in the long-term follow-up?

Cognitive function and hearing are known to both decline in older adults. As hearing loss is proposed to be one modifiable risk factor for dementia, the impact of auditory rehabilitation on cognitive decline has been gaining increasing attention. Despite a large number of studies, long-term data are still rare. In a large prospective longitudinal monocentric study, 50 adults (aged ≥ 50 years) with severe postlingual bilateral hearing loss received a cochlear implant (CI). They underwent comprehensive neurocognitive testing prior to implantation (T1), at 12 months (T2) and up to 65 months (T3) after implantation. Various cognitive subdomains such as attention, inhibition, working memory, verbal fluency, mental flexibility and (delayed) recall were assessed by the computer-based non-auditory test battery ALAcog^©. The observed trajectories of two exemplary cognitive subdomains (delayed recall and working memory) were then fitted over time using multilevel growth models to adjust for sociodemographic covariates and compared with 5-year longitudinal data from a sample of older adults from the representative Survey of Health, Aging and Retirement in Europe (SHARE) study. Postoperatively, auditory functions improved from 6.98% (SD 12.83) to 57.29% (SD 20.18) in monosyllabic speech understanding. Cognitive functions significantly increased from T1 to T3 in attention (p = 0.001), delayed recall (p = 0.001), working memory (OSPAN; p = 0.001), verbal fluency (p = 0.004), and inhibition (p = 0.002). A closer look at follow-up revealed that cognitive improvement could be detected between T1 and T2 and thereafter remained stable in all subtests (p ≥ 0.06). Additional longitudinal analysis confirmed these findings in a rigorous multilevel approach in two exemplary cognitive subdomains. In contrast to the SHARE data, there was no evidence for age-differential associations over time in CI recipients. This suggests that older adults benefit equally from cochlear implantation. CI users with worse preoperative cognitive skills experienced the most benefit (p < 0.0001). Auditory rehabilitation by cochlear implantation has a stimulating effect on cognitive functions beyond an improvement in speech understanding and an increased well-being. Large multicenter studies using standardized protocols have to be undertaken in the future to find out whether hearing restoration might help to prevent cognitive decline.

Cognitive and behavioral effects of hearing loss

PURPOSE OF REVIEW

Hearing loss is one of the largest modifiable risk factors for developing dementia, accounting for up to 9% of the overall modifiable risk. The neuropsychologic and psychosocial impacts of hearing loss are becoming increasingly appreciated. The objective of this review is to explore the recent literature regarding the cognitive and behavioral effects of hearing loss and the role of hearing rehabilitation, particularly in older adults.

RECENT FINDINGS

Cognitive decline may begin while patients have subclinical hearing loss, earlier than previously thought. Hearing rehabilitation, either via hearing amplification, middle ear surgery, or cochlear implantation, likely plays a role in preventing or slowing the rate of cognitive decline in patients with hearing loss. Hearing loss can increase the likelihood of social isolation, loneliness and depression in older adults, but it is unclear at this time what effect hearing rehabilitation has on these domains.

SUMMARY

Hearing loss is one of the largest modifiable risk factors for cognitive decline, and hearing rehabilitation can play a significant role in preserving cognitive function. Understanding the cognitive and psychosocial impact of hearing loss can help facilitate the development of approaches for prevention and treatment.

The effect of risk factors on cognition in adult cochlear implant candidates with severe to profound hearing loss

Hearing loss has been identified as a major modifiable risk factors for dementia. Adult candidates for cochlear implantation (CI) represent a population at risk of hearing loss-associated cognitive decline. This study investigated the effect of demographics, habits, and medical and psychological risk factors on cognition within such a cohort. Data from 34 consecutive adults with post-lingual deafness scheduled for CI were analyzed. Pure tone audiometry (PTA4) and Speech Discrimination Score (SDS) were recorded. The Repeatable Battery for Assessment of Neuropsychological Status for Hearing impaired individuals (RBANS-H) was used to measure cognition. Demographics (sex, age, years of education), habits (smoking, alcohol intake, physical inactivity), and medical factors (hypertension, diabetes, traumatic brain injury) were evaluated. Depression was measured using the Hospital Anxiety and Depression Scale (HADS), and social inhibition with the Type D questionnaire (DS14). All participants (mean age 62 ± 15 years) suffered from severe to profound hearing loss (PTA4:129 ± 60 dB; SDS:14 ± 24%). The mean RBANS-H total score was 83 ± 16. Participants reported a mean of years of formal education of 12 ± 5 years. The prevalence of habits and medical risk factors was: physical inactivity (29%), body mass index >30 (28%), traumatic brain injury (25%), hypertension (24%), heavy alcohol consumption (13%), smoking (13%), and diabetes (0%). Regarding psychological factors, the mean scores of social inhibition and depression were 10 ± 6 and 6 ± 5, respectively. The number of years of education was significantly correlated with the RBANS-H total score (p < 0.001), and with the domains “Immediate memory” (p = 0.003), “Visuospatial/constructional” (p < 0.001), and “Attention” (p < 0.001). The mean RBANS-H total score in participants who had university studies or higher level (12/34) was 97 ± 9, with the remaining participants reporting a mean score of 75 ± 15. Men performed better in the “Visuospatial/constructional” (p = 0.008). Physical inactivity was associated with lower scores in the “Delayed memory” (p = 0.031); hypertension correlated with lower RBANS-H total scores (p = 0.025) and “Attention” (p = 0.006). Depression and social inhibition were negatively correlated with RBANS-H total score and with the “Immediate memory,” “Visuospatial/constructional,” and “Attention” (all p < 0.05). In adults with late-onset deafness scheduled to CI, educational level has a significant effect. Additionally, sex, physical inactivity, hypertension, and psychological traits of social inhibition and depression may also influence cognitive status. Long-term studies with more participants would enable us better understand the effects different risk factors on cognitive status.

Changes in cognitive performance after cochlear implantation in adults and older adults: a systematic review and meta-analysis

OBJECTIVES

To conduct critical assessment of the literature on the effects of cochlear implantation on adults' cognitive abilities.

DESIGN

PubMed, Scopus, Lilacs, Web of Science, Livivo, Cochrane, Embase, PsycInfo, and grey literature were searched. Eligibility criteria: age 18 or over with severe-to-profound bilateral hearing loss, cochlear implantation, cognitive test before and after implantation. Risk of bias was assessed using ROB, ROBINS-I and MASTARI tools. Meta-analysis was performed.

STUDY SAMPLE

Out of 1830 studies, 16 met the inclusion criteria.

RESULTS

On AlaCog test, significant improvement was found after implantation [MD = -46.64; CI95% = -69.96 to -23.33; I² = 71%]. No significant differences were found on the Flanker, Recall, Trail A and n-back tests (p > 0.05). For MMSE, no significance was found [MD 0.63; CI 95% = -2.19 to 3.45; I² = 88%]. On TMT, an overall significant effect with a 9-second decrease in processing speed post-implantation [MD = -9.43; CI95% = -15.42 to -3.44; I² = 0%].

CONCLUSION

Cognitive improvements after cochlear implantation may depend on time and the cognitive task evaluated. Well-designed studies with longer follow-up are necessary to examine whether cochlear implantation has a positive influence on cognitive abilities. Development of cognitive assessment tools to hearing-impaired individuals is needed.

Cognition and Cognitive Reserve in Cochlear Implant Recipients

At present, dementia is a hot topic. Hearing loss is considered to be a modifiable risk factor for cognitive decline. The underlying mechanism remains unclear and might be mediated by socioeconomic and psychosocial factors. Cochlear implantation has been shown not only to restore auditory abilities, but also to decrease mental distress and to improve cognitive functions in people with severe hearing impairment. However, the promising results need to be confirmed. In a prospective single-center study, we tested the neurocognitive abilities of a large group of 71 subjects with bilateral severe hearing impairment with a mean age of 66.03 (SD = 9.15) preoperatively and 6, 12, and 24 months after cochlear implantation using a comprehensive non-auditory computer-based test battery, and we also assessed the cognitive reserve (CR) [Cognitive Reserve Index (CRI)], health-related quality of life (QoL) (Nijmegen Cochlear Implant Questionnaire), and depression (Geriatric Depression Scale-15). Cognitive functions significantly increased after 6 months in attention (p = 0.00004), working memory (operation span task; p = 0.002), and inhibition (p = 0.0002); and after 12 months in recall (p = 0.003) and verbal fluency (p = 0.0048), and remained stable up to 24 months (p ≥ 0.06). The CR positively correlated with cognitive functions pre- and post-operatively (both p < 0.005), but postoperative improvement in cognition was better in subjects with poor CR (p = 0.003). Depression had only a slight influence on one subtest. No correlation was found among cognitive skills, quality of life, and speech perception (each p ≥ 0.05). Cochlear implantation creates an enriched environment stimulating the plasticity of the brain with a global positive impact on neurocognitive functions, especially in subjects with poor preoperative cognitive performance and low cognitive reserve.

Effect of cochlear implantation on cognitive decline and quality of life in younger and older adults with severe-to-profound hearing loss

Purpose

(a) To measure the change in cognition, the improvement of speech perception, and the subjective benefit in people under and over 60 years following cochlear implantation. (b) To assess the relationship between cognition, demographic, audiometric, and subjective outcomes in both age groups.

Methods

28 cochlear implant (CI) users were assigned to the < 60y group and 35 to the ≥ 60y group. Cognition was measured using the Repeatable Battery for the Assessment of Neuropsychological Status for Hearing impaired individuals (RBANS-H); subjective benefit was measured using the Nijmegen Cochlear Implant Questionnaire (NCIQ); the Glasgow Benefit Inventory (GBI); the Hearing Implant Sound Quality Index (HISQUI₁₉); Speech, Spatial and Qualities of Hearing Scale (SSQ₁₂); and the Hospital Anxiety and Depression Scale (HADS).

Results

Prior to surgery: the RBANS-H total score positively correlated with the domains “Advanced sound”, “Self-esteem”, and “Social functioning” of NCIQ, and negatively with HADS scores. 12 months post-implantation: the RBANS-H total score increased in the < 60y (p = 0.038) and in the ≥ 60y group (p < 0.001); speech perception and subjective outcomes also improved; RBANS-H total score positively correlated with “Self-esteem” domain in NCIQ. Age and the RBANS-H total score correlated negatively in the ≥ 60y group (p = 0.026).

Conclusions

After implantation, both age groups demonstrated improved cognition, speech perception and quality of life. Their depression scores decreased. Age was inversely associated with cognition.

The bone conduction implant BONEBRIDGE increases quality of life and social life satisfaction

PURPOSE

Transcutaneous active bone conduction hearing aids represent an alternative approach to middle ear surgery and conventional hearing aids for patients with conductive or mixed hearing loss. The aim of this study was to determine quality of life, subjective hearing experience and patients' satisfaction after implantation of a bone conduction hearing aid.

METHODS

This monocentric and retrospective study included twelve adult patients who received a bone conduction hearing aid (Bonebridge, MedEL) consisting of an extracorporeal audio processor and a bone conduction implant (BCI) between 2013 and 2017. On average 40 months after implantation, the patients were asked to answer three questionnaires regarding quality of life (AqoL-8D), self-reported auditory disability (SSQ-12-B) and user's satisfaction (APSQ) after implantation of the Bonebridge (BB). A descriptive statistical analysis of the questionnaires followed.

RESULTS

12 patients aged 26-85 years (sex: m = 7, w = 5) were recruited. The quality of life of all patients after implantation of the BB (AqoL 8D) averaged an overall utility score of 0.76 (SD ± 0.17). The mean for 'speech hearing' in the SSQ-12-B was + 2.43 (SD ± 2.03), + 1.94 (SD ± 1.48) for 'spatial hearing' and + 2.28 (SD ± 2.32) for 'qualities of hearing'. 11 out of 12 patients reported an improvement in their overall hearing. The APSQ score for the subsection 'wearing comfort' was 3.50 (SD ± 0.87), 'social life' attained a mean of 4.17 (SD ± 1.06). The 'device inconveniences' reached 4.02 (SD ± 0.71) and 'usability' of the device was measured at 4.23 (SD ± 1.06). The average wearing time of the audio processor in the cohort was 11 h per day, with 8 of 12 patients reporting the maximum length of 12 h per day.

CONCLUSION

BB implantation results in a gain in the perceived quality of life (AqoL 8D). The SSQ-12-B shows an improvement in subjective hearing. According to the APSQ, it can be assumed that the BB audio processor, although in an extracorporeal position, is rated as a useful instrument with positive impact on social life. The majority stated that they had subjectively benefited from BB implantation and that there were no significant physical or sensory limitations after implantation.

Multicentre cohort study of cochlear implantation outcomes in Thailand

OBJECTIVES

To report the status and outcomes of cochlear implantation in Thailand.

DESIGN

Cohort study.

SETTING

Tertiary care and university hospitals.

PARTICIPANTS

Patients who underwent cochlear implant surgery in Thailand.

INTERVENTIONS

This project collected data from all government and university hospitals in Thailand where cochlear implant surgery was performed between 2016 and 2020.

PRIMARY AND SECONDARY OUTCOME MEASURES

Baseline characteristics, operation data, complications, audiological outcomes and quality of life were reported.

RESULTS

This study included 458 patients, and nearly half of the patients were children and adolescents (46.94%). The mean age of the patients was 2.96±5.83 years. At 1 year postoperatively, the mean pure tone average of the hearing threshold in the implanted ear significantly improved from unaided preoperative baseline (mean difference (MD) 64.23 dB HL; 95% CI 59.81 to 68.65; p<0.001). The mean speech recognition threshold also improved (MD 55.96 dB HL; 95% CI 49.50 to 62.42, p<0.001). The quality-of-life scores of the EQ-5D-5L, PedsQL and HUI3 questionnaires at 1 year showed improved mobility (range, 0-5; MD 0.65; 95% CI 0.05 to 1.25; p=0.037), hearing (range, 0-6; MD 0.96; 95% CI 0.30 to 1.61; p=0.006) and speech (range, 0-5; MD 0.44; 95% CI 0.04 to 0.84; p=0.031). Common complications included electrode dislodgement (2.18%), vertigo (1.23%) and meningitis (1.93%).

CONCLUSIONS

Excellent audiological outcomes and improvement in the quality of life in the mobility, hearing and speech domains were observed in patients who underwent cochlear implantation in Thailand.

Improvement of Working Memory and Processing Speed in Patients over 70 with Bilateral Hearing Impairment Following Unilateral Cochlear Implantation

Several studies demonstrated the association of hearing disorders with neurocognitive deficits and dementia disorders, but little is known about the effects of auditory rehabilitation on the cognitive performance of the elderly. Therefore, the research question of the present study was whether cochlear implantation, performed in 21 patients over 70 with bilateral severe hearing impairment, could influence their cognitive skills. The measuring points were before implantation and 12 months after the first cochlear implant (CI) fitting. Evaluation of the working memory (WMI) and processing speed (PSI) was performed using the Wechsler Adult Intelligence Scale 4th edition (WAIS-IV). The audiological assessment included speech perception (SP) in quiet (Freiburg monosyllabic test; FMT), noise (Oldenburg sentence test; OLSA), and self-assessment inventory (Oldenburg Inventory; OI). Twelve months after the first CI fitting, not only the auditory parameters (SP and OI), but also the WMI and PSI, improved significantly (p < 0.05) in the cohort. The presented results imply that cochlear implantation of bilaterally hearing-impaired patients over 70 positively influences their cognitive skills.

Sensory Dysfunction in Old Age

BACKGROUND

The senses serve as the crucial interface between the individual and the environment. They are subject to aging and disease processes.

METHODS

This review is based on pertinent publications retrieved by a selective search in the Medline and Cochrane Library databases.

RESULTS

Approximately 40% of persons aged 70 to 79 manifest dysfunction in at least one, and more than 25% in multiple senses. Sensory changes are accompanied by diverse comorbidities which depend on the particular sense(s) affected. The presence of sensory deficits is associated with an increased risk of developing dementia (OR: 1.49 [95% confidence interval: 1.12; 1.98] for dysfunction in a single sensory modality, 2.85 [1.88; 4.30] for dysfunction in three or more sensory modalities). The risk of developing depressive symptoms is elevated as well (OR 3.36 [2.28; 4.96]). The individual's ability to cope with the demands of everyday life is largely determined by the ability to carry out multisensory integration, in which the perceptions of the different senses are bound together. This function itself is subject to age-related changes that can be either adaptive or maladaptive; it can, therefore, serve as an indicator for pathological aging processes.

CONCLUSION

Sensory dysfunction in old age should be detected as early as possible. This implies the need for close collaboration of all of the involved disciplines. It would be desirable to develop sensory screening tests as well as a procedure for testing multisensory integration in routine clinical practice.