Cochlear implantation outcomes in older adults

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 Implantation in Patients With Known Cognitive Impairment: What Are the Benefits?

OBJECTIVE

To evaluate the outcomes of cochlear implantation (CI) in adults with preoperatively diagnosed cognitive impairment.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary-care academic center.

PATIENTS

Adults undergoing CI with preexisting cognitive impairment.

INTERVENTIONS

Cochlear implantation.

MAIN OUTCOME MEASURES

1) Hearing improvement after CI; 2) morbidity and mortality associated with surgery.

RESULTS

Eight patients met inclusion criteria with mean age 77.8 years (SD, 9.6 y) at time of implantation; 7 were included in subsequent analysis as one did not have speech recognition scores. Average preoperative MoCA cognitive score of 22.6 (SD, 3.9, ≤25 demonstrates cognitive impairment). Average follow-up was 29.0 months (SD, 33.3 mo). Two patients passed away at an average 58.0 months (SD, 31.1 mo) after surgery. Median preoperative pure tone average was 86.3 dB HL ( interquartile range 31.3 dB HL) compared with 33.8 dB HL (IQR 5.0 dB HL) postoperatively ( p = <0.001). Median preoperative speech testing score (AzBio/HINT) was 21% (IQR, 24%) compared with 44% (IQR, 21%) postoperatively ( p = <0.001). There were no observed surgical complications during the follow-up period.

CONCLUSIONS

This study demonstrates that patients with cognitive impairment before CI can experience improved hearing, no increased risk of complications, and good longevity after CI. Further prospective studies are needed to further define the utility of CI in patients with impaired cognition.

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.

Caregiver Quality of Life After Cochlear Implantation in Older Adults

OBJECTIVE

To evaluate factors affecting quality of life (QOL) in caregivers of older cochlear implant (CI) recipients.

STUDY DESIGN

Cross-sectional survey.

SETTING

Academic medical center.

PATIENTS

Adults over age 65 receiving CI between July 13, 2000 and April 3, 2019.

INTERVENTIONS

Cochlear implantation.

MAIN OUTCOME MEASURES

Linear regression models for caregiver QOL measured by Significant Other Scale for Hearing Disability (SOS-HEAR), with independent variables: caregiver role, patient gender, 11 factor modified frailty index (mFI), duration of hearing loss, hearing aid use, age at surgery, time since surgery, change in pure tone average (PTA), processor input type and Nijmegen Cochlear Implant Questionnaire (NCIQ). Correlations between SOS-HEAR and patient speech recognition scores.

RESULTS

Questionnaires were mailed to all 294 living CI recipients. Seventy-one caregivers completed the questionnaire. Only patient gender and mFi were significant predictors of caregiver QOL on both univariate (p ≤ 0.001, β= -20.26 [95% confidence interval -30.21, -10.3]; 0.005, -0.72 [-1.20, -0.23], respectively) and multivariate (p = 0.005, β = -20.09, -33.05 to -7.13; 0.003, -0.93 [-1.50, -0.37]) analysis, where caregivers of female patients with lower mFI (better health) had better QOL scores. Caregiver QOL was significantly associated with patient's change in PTA and self-reported QOL scores on univariate (p = 0.041, β = 0.52 [0.08, 0.96]; 0.024, -0.27 [-0.52, -0.02]) but not multivariate analysis. Time since CI was significant only on multivariate analysis (0.041, -0.17 [-0.33, -0.01]). Caregiver QOL did not correlate with patient speech recognition scores.

CONCLUSIONS

Higher QOL scores were found among caregivers of healthier, female CI recipients. Patient hearing measurements did not correspond with better caregiver QOL.

The Impact of Cochlear Implantation: Cognitive Function, Quality of Life, and Frailty in Older Adults

This review examines the relationship between cochlear implantation and cognition and quality of life in older adults, as well as how frailty affects outcomes for older patients with cochlear implants. A growing body of evidence suggests that there is a strong association between hearing loss and cognitive impairment. Preliminary studies suggest that cochlear implantation in older adults may be protective against cognitive decline. While studies have observed a positive impact of cochlear implantation on quality of life, currently it is unclear what factors contribute the most to improved quality of life. Frailty, as a measurement of general health, likely plays a role in complication rates and quality-of-life outcomes after cochlear implantation, though larger prospective studies are required to further elucidate this relationship.

Unilateral Cochlear Implants for Severe, Profound, or Moderate Sloping to Profound Bilateral Sensorineural Hearing Loss: A Systematic Review and Consensus Statements

Importance

Cochlear implants are a treatment option for individuals with severe, profound, or moderate sloping to profound bilateral sensorineural hearing loss (SNHL) who receive little or no benefit from hearing aids; however, cochlear implantation in adults is still not routine.

Objective

To develop consensus statements regarding the use of unilateral cochlear implants in adults with severe, profound, or moderate sloping to profound bilateral SNHL.

Design, Setting, and Participants

This study was a modified Delphi consensus process that was informed by a systematic review of the literature and clinical expertise. Searches were conducted in the following databases: (1) MEDLINE In-Process & Other Non-Indexed Citations and Ovid MEDLINE, (2) Embase, and (3) the Cochrane Library. Consensus statements on cochlear implantation were developed using the evidence identified. This consensus process was relevant for the use of unilateral cochlear implantation in adults with severe, profound, or moderate sloping to profound bilateral SNHL. The literature searches were conducted on July 18, 2018, and the 3-step Delphi consensus method took place over the subsequent 9-month period up to March 30, 2019.

Main Outcomes and Measures

A Delphi consensus panel of 30 international specialists voted on consensus statements about cochlear implantation, informed by an SR of the literature and clinical expertise. This vote resulted in 20 evidence-based consensus statements that are in line with clinical experience. A modified 3-step Delphi consensus method was used to vote on and refine the consensus statements. This method consisted of 2 rounds of email questionnaires and a face-to-face meeting of panel members at the final round. All consensus statements were reviewed, discussed, and finalized at the face-to-face meeting.

Results

In total, 6492 articles were identified in the searches of the electronic databases. After removal of duplicate articles, 74 articles fulfilled all of the inclusion criteria and were used to create the 20 evidence-based consensus statements. These 20 consensus statements on the use of unilateral cochlear implantation in adults with SNHL were relevant to the following 7 key areas of interest: level of awareness of cochlear implantation (1 consensus statement); best practice clinical pathway from diagnosis to surgery (3 consensus statements); best practice guidelines for surgery (2 consensus statements); clinical effectiveness of cochlear implantation (4 consensus statements); factors associated with postimplantation outcomes (4 consensus statements); association between hearing loss and depression, cognition, and dementia (5 consensus statements); and cost implications of cochlear implantation (1 consensus statement).

Conclusions and Relevance

These consensus statements represent the first step toward the development of international guidelines on best practices for cochlear implantation in adults with SNHL. Further research to develop consensus statements for unilateral cochlear implantation in children, bilateral cochlear implantation, combined electric-acoustic stimulation, unilateral cochlear implantation for single-sided deafness, and asymmetrical hearing loss in children and adults may be beneficial for optimizing hearing and quality of life for these patients.

How great is the negative impact of masking and social distancing and how can we enhance communication skills in the elderly people?

During COVID-19 pandemic, protective measures such as social distancing and face masks posed a challenge in daily communication, in this context the elderly are one of the most at risk categories as widely exposed to hearing loss. This article focuses on how the COVID-19 pandemic affected verbal communication, especially on those people that even in normal conditions present an increased difficulty in speech perception. Special attention has been paid to hearing aids and cochlear implant users, these devices indeed can be affected by a speech intelligibility reduction and could be uncomfortable if used together with face masks. Possible alternatives and solutions will be proposed to reduce the negative impacts of face coverings on communication, to enhance speech intelligibility and to manage wearability of hearing rehabilitation devices.

Frailty and Quality of Life After Cochlear Implantation in Older Adults

OBJECTIVE

To examine the relationship among frailty index, hearing measures, and hearing-related quality of life (QOL) in older recipients of cochlear implants.

STUDY DESIGN

Cross-sectional survey.

SETTING

Academic medical center.

METHODS

Adults aged ≥65 years at the time of receiving cochlear implants between July 13, 2000, and April 3, 2019, were asked to complete a questionnaire on hearing-related QOL. Chart review was performed to identify patients' characteristics. Correlations were calculated between frailty index and audiologic outcome measures as well as between speech recognition scores and QOL scores. Linear regression models were developed to examine the impact of clinical characteristics, frailty index, and hearing measures on hearing-related QOL.

RESULTS

Data for 143 respondents were included. The mean age was 80.7 years (SD, 7.1), with a mean 27.8 years of hearing loss (SD, 17.4) before implantation. The mean frailty index was 11.1 (SD, 10.6), indicating that patients had 1 or 2 of the measured comorbidities on average. No correlation was found between lower frailty index (better health) and hearing scores, including pure tone averages (PTAs) and speech recognition scores. Lower frailty index and larger improvement in PTA after cochlear implantation predicted better QOL scores on univariate analysis (respectively, P = .002, β = -0.42 [95% CI, -0.68 to -0.16]; P = .008, β = -0.15 [95% CI, -0.26 to -0.04]) and multivariate analysis (P = .047, β = -0.28 [95% CI, -0.55 to -0.01]; P = .006, β = -0.16 [95% CI, -0.28 to -0.05]). No speech recognition scores correlated with QOL after cochlear implantation.

CONCLUSIONS

Frailty index does not correlate with hearing scores after cochlear implantation in older adults. Lower frailty index and more improvement in PTA predict better QOL scores after cochlear implantation in older adults.

Visual and Auditory Verbal Memory in Older Adults: Comparing Postlingually Deaf Cochlear Implant Users to Normal-Hearing Controls

Purpose The aim of this study was to test whether a group of older postlingually deafened cochlear implant users (OCIs) use similar verbal memory strategies to those used by older normal-hearing adults (ONHs). Verbal memory functioning was assessed in the visual and auditory modalities separately, enabling us to eliminate possible modality-based biases. Method Participants performed two separate visual and auditory verbal memory tasks. In each task, the visually or aurally presented study words were learned by vocal production (saying aloud) or by no production (reading silently or listening), followed by a free recall test. Twenty-seven older adults (> 60 years) participated (OCI = 13, ONH = 14), all of whom demonstrated intact cognitive abilities. All OCIs showed good open-set speech perception results in quiet. Results Both ONHs and OCIs showed production benefits (higher recall rates for vocalized than nonvocalized words) in the visual and auditory tasks. The ONHs showed similar production benefits in the visual and auditory tasks. The OCIs demonstrated a smaller production effect in the auditory task. Conclusions These results may indicate that different modality-specific memory strategies were used by the ONHs and the OCIs. The group differences in memory performance suggest that, even when deafness occurs after the completion of language acquisition, the reduced and distorted external auditory stimulation leads to a deterioration in the phonological representation of sounds. Possibly, this deterioration leads to a less efficient auditory long-term verbal memory.

Does Treating Hearing Loss in Older Adults Improve Cognitive Outcomes? A Review

Hearing loss is the third most prevalent health condition in older age. In recent years, research has consistently reported an association between hearing loss and mental health outcomes, including poorer cognitive performances. Whether treating hearing loss in elders improves cognition has been directly or indirectly addressed by several studies. This review aims at providing a synthesis of those results. Regarding the literature on hearing aids’ use and cognition, although the lack of interventional studies has to be underlined, observational data suggest that hearing aids positively impact long-term cognition, even though more research is necessary to ascertain this statement and provide information on the length or frequency of use required in order to observe benefits. Regarding cochlear implants in elders experiencing more severe auditory deprivation, the literature is scarcer. The available studies have many limitations and do not allow the drawing of clear conclusions. Taken together, the results are encouraging. Nevertheless, because hearing loss is suspected to account for 9% of dementia cases, and also because hearing loss is one of the few potentially modifiable factors from a dementia prevention perspective, the need to stimulate research to have clearer knowledge of the benefits of treating hearing loss on cognitive outcomes is urgent.

Age-related hearing loss and tinnitus, dementia risk, and auditory amplification outcomes

Age-related hearing loss (ARHL) or presbycusis, as the third leading cause of chronic disability in older adults, has been shown to be associated with predisposing cognitive impairment and dementia. Tinnitus is also a chronic auditory disorder demonstrating a growth rate with increasing age. Recent evidence stands for the link between bothersome tinnitus and impairments in various aspects of cognitive function. Both ARHL and age-related tinnitus affect mental health and contribute to developing anxiety, stress, and depression. The present review is a comprehensive multidisciplinary study on diverse interactions among ARHL, tinnitus, and cognitive decline in older adults. This review incorporates the latest evidence in prevalence and risk factors of ARHL and tinnitus, the neural substrates of tinnitus-related cognitive impairments, hypothesized mechanisms concerning the association between ARHL and increased risk of dementia, hearing amplification outcomes in cases with ARHL and cognitive decline, and preliminary findings on the link between ARHL and cognitive impairment in animal studies. Given extensive evidence that demonstrates advantages of using auditory amplification in the alleviation of hearing handicap, depression, and tinnitus, and the improvement of cognition, social communication, and quality of life, regular hearing screening programs for identification and management of midlife hearing loss and tinnitus is strongly recommended.

Cognitive Performance of Severely Hearing-impaired Older Adults Before and After Cochlear Implantation: Preliminary Results of a Prospective, Longitudinal Cohort Study Using the RBANS-H

OBJECTIVE

To evaluate cognitive change in severely hearing-impaired older adults after cochlear implantation.

STUDY DESIGN

Prospective, longitudinal cohort study with assessments before, and at 6 and 12 months after implantation.

PATIENTS

Twenty older adults (median age: 71.5 yr).

MAIN OUTCOME MEASURES

Change in the Repeatable Battery for the Assessment of Neuropsychological Status for Hearing-impaired individuals (RBANS-H) total score and subdomain scores were used to assess cognitive evolution. In addition, change in best-aided speech audiometry in quiet (monosyllabic words) and in noise (Leuven Intelligibility Sentences Test [LIST]) was examined, as well as patient-reported measures of health-related quality of life (Nijmegen Cochlear Implant Questionnaire [NCIQ]), self-perceived hearing disability (Speech, Spatial, and Qualities of hearing Scale-12 [SSQ12]), sound quality (Hearing Implant Sound Quality Index-19 [HISQUI19]), and states of anxiety and depression (Hospital Anxiety and Depression Scale [HADS]).

RESULTS

The RBANS-H total scores improved significantly after 12 months cochlear implant (CI) usage (p < 0.001). At subdomain level, significant improvements were observed in the immediate and delayed memory domain (p = 0.005 and p = 0.002, respectively), and to a lesser extent also in the attention domain (p = 0.047). Furthermore, speech perception in quiet and in noise improved significantly after 6 months and remained stable after 12 months. Similarly, a significant improvement was observed on all patient-reported measures after 6 months of CI usage. These results remained stable after 12 months, except for the HADS.

CONCLUSIONS

A significant improvement in overall cognition after 12 months of CI usage was established. However, future research is imperative to further disentangle possible practice effects from the effects of the cochlear implantation. The significant, positive effect of cochlear implantation on speech perception and patient-reported measures was confirmed.

Cochlear Implant in the Elderly: Results in Terms of Speech Perception and Quality of Life

Objectives: The aim of this study was to evaluate the results after cochlear implant (CI) in elderly patients and to compare them to those obtained in younger adult patients. A possible correlation between the results in older CI recipients and some variables of the patients was also investigated. Methods: The sample consisted of 107 patients over 40 years of age at surgery divided into 3 subgroups according to age at implantation. Results in terms of speech perception in silence and with background noise were compared between the 3 groups. The patients also completed the Glasgow Benefits Inventory (GBI) questionnaire. Results: Older patients achieved significant benefits after CI with regard to speech perception in silence and with background noise. We also recorded benefits for the GBI. Discussion: In line with the literature, our data confirm that CI is an effective procedure also in elderly patients, conferring benefits in speech perception and quality of life.