This cohort study examines the association between loneliness and the incidence of disability among older Japanese adults stratified by hearing impairment.
Key Points
Question
Is the association between loneliness and the incidence of disability moderated by the presence or absence of hearing impairment?
Findings
In this 2-year longitudinal cohort study of 4739 community-dwelling older Japanese adults stratified by hearing impairment, loneliness was associated with the incidence of new disability when hearing impairment was present.
Meaning
Loneliness may hasten the future incidence of disability in older adults with hearing impairment, and there is a growing need for appropriate hearing impairment and loneliness management for older adults to prevent the incidence of disability.
Abstract
Importance
Loneliness is suggested to negatively affect physical and mental health and influence the development of disability; however, a consensus on the relationship between loneliness and disability has not been reached. Age-related hearing impairment worsens the daily-life activities of older adults, and the association between loneliness and the incidence of disability may be influenced by hearing impairment.
Objective
To examine the association between loneliness and the incidence of disability among older adults stratified by hearing impairment.
Design, Setting, and Participants
This prospective observational cohort study included 5563 community-dwelling adults 65 years or older who participated in functional health examinations in Tokai City, Aichi Prefecture, Japan, between September 2017 and June 2018. Data analysis was conducted from August 2022 to February 2023.
Main Outcomes and Measures
Cox proportional hazards regression models were used to examine the association between loneliness and the incidence of disability stratified by hearing impairment.
Results
Among the 4739 participants who met the inclusion criteria (mean [SD] age, 73.8 [5.5] years; 2622 [55.3%] female), 3792 (80.0%) were without hearing impairment and 947 (20.0%) were with hearing impairment. Of those who reported experiencing loneliness, 1215 (32.0%) were without hearing impairment, and 441 (46.6%) were with hearing impairment. After 2 years, the number of individuals with disabilities was 172 (4.5%) without hearing impairment and 79 (8.3%) with hearing impairment. Cox proportional hazards regression analysis showed no statistically significant association between loneliness and the incidence of disability in a model adjusted for potential confounding factors among community-dwelling older adults without hearing impairment (hazard ratio, 1.10; 95% CI, 0.80-1.52). Among community-dwelling older adults with hearing impairment, a model adjusted for potential confounding factors showed a statistically significant association between loneliness and the incidence of disability (hazard ratio, 1.71; 95% CI, 1.04-2.81).
Conclusions and Relevance
This cohort study found that the association between loneliness and the incidence of disability was moderated by the presence or absence of hearing impairment. Hearing impairment is the most common symptom of geriatric syndromes, showing that among the various risk factors, loneliness may require special attention in the prevention of disability in people with hearing impairment.
Introduction
Age-related hearing impairment is reported to be the most common age-related sensory impairment,1 with an estimated 1.57 billion individuals worldwide with hearing impairment in 2019.2 Additionally, 20% to 45% of older adults experience loneliness,3,4 suggesting that high rates of both loneliness and hearing impairment are present in older adults. Older adults with hearing impairment have difficulty decoding and discriminating speech from background noise, consequently reducing communication skills and hearing-dependent activities.5,6 Age-related hearing impairment has been reported to decrease daily-life activities and is a factor in the narrowing of living space.7,8 In addition, communication difficulties due to hearing impairment can negatively influence older adults’ social life and social networks9,10 and increase loneliness.11
Loneliness is caused by distress and dissatisfaction due to perceived unfulfilled social relationships12 and is suggested to negatively affect various aspects of mental and physical health.4 However, this has not been adequately examined in older adults with hearing impairment. Previous studies reported that individuals with hearing and other sensory impairments are more likely to experience discrimination13 and exhibit depressive symptoms and feelings of loneliness.14,15 In addition, older adults with hearing impairment have reportedly been associated with physical frailty, such as reduced walking speed and physical activity.16 Self-reported hearing impairment was associated with a statistically significant higher risk of becoming frail or prefrail 4 years later.16
Increased medical and care costs due to the development of physical and mental illnesses caused by loneliness have been focused on as a social issue, and in 2018, a Minister for Loneliness was established in the UK. In 2021 in Japan, the government established a directorate for loneliness and isolation, which is considered to be an urgent issue at the national level. Hearing impairment has been reported to limit communication with others and is a risk factor for various psychiatric symptoms, including depression and loneliness.17,18 Hearing impairment has also been reported to reduce living space7 and to be associated with social frailty in addition to physical frailty,16,19 and it is expected to be strongly associated with loneliness and the incidence of disability. However, the influence of hearing impairment on loneliness and the incidence of disability has rarely been examined. Therefore, this cohort study aimed to examine whether the association between loneliness and the incidence of disability is moderated by the presence or absence of hearing impairment.
Methods
Participants
This longitudinal study involved community-dwelling older Japanese adults who were recruited from a subcohort of the National Center for Geriatrics and Gerontology Study of Geriatric Syndrome. The Study of Geriatric Syndrome is a large cohort study that aims to identify the risks of geriatric syndromes that occur with aging and effective ways to treat them. The present study’s inclusion criteria comprised individuals 65 years or older who resided in Tokai City, Aichi Prefecture, Japan. Overall, 5563 individuals participated face to face in the baseline health checkup survey.
All baseline assessments were performed by well-trained nurses and study assistants in community centers. All staff received training from the authors regarding the protocols for administering the assessments prior to study commencement.
The following exclusion criteria were applied: (1) those with a history of dementia, Parkinson disease, or stroke (n = 367); (2) those with impairment in basic activities of daily living (ADL; n = 12); (3) those who required support and care from the long-term care insurance (LTCI) system at the baseline assessment (n = 24); and (4) missing exclusion criteria data (n = 343). In addition, during the follow-up period, we excluded missing data on disability based on LTCI records, participants who were certified as disabled in the same month of the baseline evaluation (n = 16), deaths (n = 32), and transfers out (n = 30). Finally, 4739 participants were included in the analysis of the baseline study and the 2-year follow-up study in the incidence of disability.
All participants provided written informed consent before participating in the study. The study protocol was developed in accordance with the Declaration of Helsinki and was approved by the ethics committee of the National Center for Geriatrics and Gerontology. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.
Measures
Assessment of Self-reported Hearing Impairment and Use of Hearing Aids or Cochlear Implants
Participants reported whether they used hearing aids or cochlear implants, as instructed by trained staff. In addition, they completed the Hearing Handicap Inventory for the Elderly–Screening (HHIE-S).20 The HHIE-S questionnaire measures activity and participation restrictions caused by hearing impairment in various situations of daily life. The 10 items of the HHIE-S are divided into 2 subscales: one explores emotional consequences, and the other explores social or situational effects. Each item had 3 response options: “yes” (score of 4), “sometimes” (score of 2), and “no” (score of 0). Individuals with hearing impairment were defined as those using hearing aids or cochlear implants and those whose total HHIE-S score exceeded 8.20
Definition of Loneliness
The University of California, Los Angeles Loneliness Scale (UCLA-LS; version 3) was used as a measure of loneliness in this study.21 The UCLA-LS contains 20 items with 4 options per item: (1) never, (2) rarely, (3) sometimes, and (4) always. Higher scores in the UCLA-LS indicate higher levels of loneliness. The Japanese version of this scale has been developed and, to our knowledge, is the only Japanese loneliness scale with established reliability and validity.22 It is considered internationally comparable.23 In the present study, a score of 44 or higher was defined as experiencing loneliness, based on previous studies of older Japanese adults.22
Follow-up of Disability
Following the public LTCI system,24 participants received monthly follow-up for 2 years after the baseline assessment to monitor the need for long-term care. In Japan, all individuals 65 years and older can obtain institutional or community-based services, depending on their disability level. The Japanese government established an objective, uniform, nationwide standard for certifying the need for long-term care, which is classified into 7 levels (support level 1 or 2 and care level 1-5).24 The certification process begins with a primary determination, wherein a trained local government official visits an individual’s home and conducts an assessment of the level of required care using a standardized 74-item questionnaire pertaining to the individual’s current physical and mental condition. Subsequently, the results are entered into a computer to calculate the estimated time required for care in 9 categories (grooming, bathing, eating, toileting, transferring, assistance with instrumental ADL, behavioral problems, rehabilitation, and medical services). Thereafter, as secondary judgment, the Care Needs Certification Board, which comprises physicians, nurses, and other health and social services experts, reviews and confirms the care-needs level based on the initial computer decision, the home-visit report, and a physician’s opinion.24
Support level 1 or 2 refers to those who are able to perform basic ADL and do not require immediate nursing care but do require some assistance. On the other hand, care levels 1 through 5 are those who have difficulty performing ADL by themselves and require some kind of nursing care. In this study, any level of LTCI certification as requiring assistance or needing care was considered a disability, and the incidence of disability was defined as the point at which a participant was certified as requiring long-term care from the LTCI. In addition, if a participant moved to another city or died, follow-up was discontinued and the participant was considered to have dropped out of the study.
Potential Confounding Factors
Variables associated with risk factors for dementia,25 the leading cause of disability in Japan, and variables associated with loneliness26 were used as confounding factors in this study. The following variables were used: age, sex, body mass index, heart disease, diabetes, eye disease, education level, number of prescription medications, walking speed, current exercise habits, smoking and drinking habits (current vs previous/never, respectively), work determined by whether individuals had a current income-earning job, residential status (living alone), depression, and cognitive decline.
Depression was assessed using the 15-item Geriatric Depression Scale.27 The cutoff score of 6 or higher has a sensitivity of 82% and specificity of 75% with a structured clinical interview for depression.28 Depressive symptoms were determined if participants scored 6 or higher on the Geriatric Depression Scale.27,28,29 Cognitive function was defined as cognitive decline if their Mini-Mental State Examination score was 23 or lower.30,31 Walking speed was measured in seconds over a 2.4-m distance using a comfortable walking speed. Participants walked for an additional 2-m distance before and after the measurement to ensure a consistent speed. A digital stopwatch was used to automatically determine when participants walked past infrared sensors at the start and end of the measurement area.
Statistical Analysis
In this study, the analysis participants were 4739 community-dwelling adults 65 years and older who participated in functional health checkups in Tokai City, Aichi Prefecture, between September 2017 and June 2018, and who were available for follow-up on the occurrence of disability for a subsequent 2 years. Data analysis was conducted from August 2022 to February 2023. As the primary outcome, Cox proportional hazards regression models were used to examine the association between loneliness and disability incidence stratified by hearing impairment.
Baseline characteristics were investigated initially by classifying the participants into 2 groups by hearing impairment. For continuous variables (age, body mass index, medication, education level, walking speed, and severity of hearing impairment), normality was confirmed by Kolmogorov-Smirnov test of normality. Because normality was not found in these variables, we used the Mann-Whitney U test, a nonparametric method. Other categorical variables were compared using the χ2 test. Each effect size and 95% CI were calculated with reference to previous studies. We also examined the strength of the association based on the proposed interpretation of effect sizes in social science data.32
Subsequently, analysis was performed for disability onset based on loneliness, stratified by hearing impairment. Kaplan-Meier curves were used to estimate the cumulative rate of new disability development during the follow-up period according to the presence of loneliness at baseline, and between-group differences were examined by log-rank tests. Finally, Cox proportional hazards regression was performed to calculate the hazard ratio (HR) of new disability occurrences according to loneliness status with 95% CIs. The Kaplan-Meier curve and Cox proportional hazards regression in this study focused on the time from the baseline survey to the occurrence of new long-term care. The number of months from the baseline survey to the occurrence of new long-term care was defined as the time to the event. The Cox regression models were adjusted for the previously mentioned potential confounding factors. Analyses were conducted using SPSS Statistics software package, version 27.0 (IBM Corp).
Results
Comparison of Baseline Characteristics Between Participants With and Without Hearing Impairment
Among the 4739 participants in this study (mean [SD] age, 73.8 [5.5] years; 2622 [55.3%] female), the classification of groups by hearing-impairment status at baseline was (1) 3792 (80.0%) without hearing impairment and (2) 947 (20.0%) with hearing impairment. The incidence of new long-term care needs (per 1000 person-years) over a 2-year period was 41.7 for individuals with hearing impairment and 22.7 for those without hearing impairment (difference, 19.0; 95% CI, 13.9-25.6).
Characteristics of participants classified by hearing-impairment status are summarized in Table 1.32 In the effect sizes calculated from the results of the Mann-Whitney U test and the χ2 test, the magnitude of the difference in potential confounders between those with hearing impairment and those without hearing impairment was not statistically significant.
Table 1. Comparison of Baseline Characteristics Between Participants With and Without Hearing Impairment.
| Variable | No. (%) | Effect size (95%CI) | ||
|---|---|---|---|---|
| Overall (n = 4739) | Without hearing impairment (n = 3792) | With hearing impairment (n = 947) | ||
| Age, mean (SD), y | 73.8 (5.5) | 73.3 (5.2) | 76.0 (6.0) | 0.18 (0.15 to 0.21)a |
| Sex | ||||
| Female | 2622 (55.3) | 2171 (57.3) | 451 (47.6) | 0.08 (0.05 to 0.11)b |
| Male | 2117 (44.7) | 496 (52.4) | 1621 (42.7) | |
| BMI, mean (SD) | 23.2 (3.1) | 23.2 (3.1) | 23.2 (3.1) | 0.01 (−0.02 to 0.04)a |
| Has heart disease | 876 (18.5) | 680 (17.9) | 196 (20.7) | 0.03 (0.07 to 0.13)b |
| Has diabetes | 649 (13.7) | 505 (13.3) | 144 (15.2) | 0.02 (−0.01 to 0.05)b |
| Has eye disease | 2487 (52.5) | 1952 (51.5) | 535 (56.5) | 0.04 (0.01 to 0.07)b |
| Current smoker | 1713 (36.1) | 1322 (34.9) | 391 (41.3) | 0.05 (0.03 to 0.08)b |
| Current drinker | 1986 (41.9) | 1584 (41.8) | 402 (42.4) | 0.01 (0.01 to 0.07)b |
| No. of medications, mean (SD) | 3.1 (2.8) | 3.0 (2.7) | 3.5 (3.2) | 0.07 (0.05 to 0.10)a |
| Years of education, mean (SD) | 11.7 (2.3) | 11.8 (2.3) | 11.3 (2.3) | 0.10 (0.07 to 0.13)a |
| Currently working | 1315 (27.7) | 1102 (29.1) | 213 (22.5) | 0.06 (0.03 to 0.09)b |
| Living alone | 642 (13.6) | 515 (13.6) | 127 (13.4) | 0.01 (−0.03 to 0.03)b |
| Walking speed, mean (SD), m/s | 1.21 (0.20) | 1.22 (0.20) | 1.17 (0.21) | 0.10 (0.07 to 0.13)a |
| Has exercise habits | 1508 (31.8) | 1232 (32.5) | 276 (29.1) | 0.03 (0.00 to 0.06)b |
| Severity of hearing impairment by HHIE-S score, mean (SD) | 5.0 (7.2) | 2.0 (2.5) | 16.7 (7.9) | 0.69 (0.68 to 0.71)a |
| Has depression | 492 (10.4) | 305 (8.0) | 187 (19.7) | 0.15 (0.13 to 0.18)b |
| Has loneliness | 1656 (34.9) | 1215 (32.0) | 441 (46.6) | 0.12 (0.09 to 0.15)b |
| Has cognitive decline | 346 (7.3) | 233 (6.1) | 113 (11.9) | 0.09 (0.06 to 0.12)b |
| Newly occurring disability | 251 (5.3) | 172 (4.5) | 79 (8.3) | 0.07 (0.04 to 0.10)b |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); HHIE-S, Hearing Handicap Inventory for the Elderly–Screening.
Mann-Whitney U test was used. Effect sizes are presented, with r of 0.2 indicating a small effect; 0.5, a medium effect; and 0.8, a large effect.32
χ2 test was used. Effect sizes are presented, with φ of 0.2 indicating a small effect; 0.5, a medium effect; and 0.8, a large effect.32
Binomial Logistic Regression Showing Associations Between Loneliness and Baseline Characteristics
Table 232 summarizes the results of binomial logistic regression analysis with loneliness as the dependent variable and potential confounders as independent variables. Loneliness was associated with sex, education level, work, living alone, walking speed, exercise habits, the severity of hearing impairment, and depression.
Table 2. Binomial Logistic Regression Showing Associations Between Loneliness and Baseline Characteristics.
| Variable | Odds ratio (95% CI)a |
|---|---|
| Age | 0.99 (0.98-1.00) |
| Male sex | 1.77 (1.46-2.14) |
| Body mass index | 1.00 (0.98-1.02) |
| Has heart disease | 1.03 (0.87-1.23) |
| Has diabetes | 1.14 (0.94-1.39) |
| Has eye disease | 1.13 (0.99-1.30) |
| Current smoker | 0.87 (0.73-1.05) |
| Current drinker | 1.10 (0.96-1.27) |
| Taking medication | 1.01 (0.99-1.04) |
| Education level | 0.91 (0.88-0.94) |
| Currently working | 0.81 (0.69-0.94) |
| Living alone | 1.23 (1.02-1.48) |
| Walking speed | 0.77 (0.54-1.09) |
| Has exercise habits | 0.77 (0.67-0.88) |
| Severity of hearing impairment by HHIE-S score | 1.03 (1.02-1.04) |
| Has depression | 3.89 (3.14-4.82) |
| Has cognitive decline | 0.95 (0.74-1.22) |
| Newly occurring disability | 1.21 (0.91-1.63) |
Abbreviation: HHIE-S, Hearing Handicap Inventory for the Elderly–Screening.
An odds ratio of 2.0 indicates a small effect; 3.0, a medium effect; and 4.0, a large effect.32
Association Between Loneliness Status and Occurrence of New Disabilities by Hearing-Impairment Status
Kaplan-Meier curves for the incidence of new disabilities by loneliness status with and without hearing impairment are shown in the Figure. In the crude model, unadjusted for potential confounders, the association between loneliness and incidence of disability was found for participants without hearing impairment (HR, 1.51; 95 CI, 1,11-2.04) and with hearing impairment (HR, 1.34; 95 CI, 1.16-2.86), respectively (Tables 3 and 4). However, results adjusted for potential confounders showed an association in the presence of hearing impairment and no association in the absence of hearing impairment.
Figure. Occurrence of New Disability Associated With Loneliness Among Participants With and Without Hearing Impairment.
Table 3. Association Between Loneliness and Incidence of Disability Among Community-Dwelling Older Adults Without Hearing Impairment.
| Variable | Hazard ratio (95% CI) | ||
|---|---|---|---|
| Crude model | Model 1a | Model 2b | |
| Loneliness status | |||
| No loneliness | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Loneliness | 1.51 (1.11-2.04) | 1.34 (0.98-1.81) | 1.10 (0.80-1.52) |
| Potential confounding factors | |||
| Age | NA | 1.18 (1.15-1.21) | 1.11 (1.08-1.15) |
| Female sex | NA | 0.78 (0.57-1.05) | 1.02 (0.64-1.62) |
| Body mass index | NA | NA | 0.98 (0.93-1.02) |
| Has heart disease | NA | NA | 0.92 (0.62-1.37) |
| Has diabetes | NA | NA | 1.11 (0.73-1.69) |
| Has eye disease | NA | NA | 0.85 (0.61-1.19) |
| Current smoker | NA | NA | 0.90 (0.55-1.45) |
| Current drinker | NA | NA | 0.90 (0.63-1.28) |
| Taking medication | NA | NA | 1.04 (0.99-1.10) |
| Education level | NA | NA | 0.98 (0.91-1.05) |
| Currently working | NA | NA | 0.77 (0.50-1.20) |
| Living alone | NA | NA | 0.69 (0.48-1.01) |
| Walking speed | NA | NA | 0.15 (0.07-0.32) |
| Has exercise habits | NA | NA | 1.64 (1.08-2.48) |
| Has depression | NA | NA | 1.26 (0.82-1.95) |
| Has cognitive decline | NA | NA | 2.65 (1.82-3.86) |
Abbreviation: NA, not applicable.
Model 1 was adjusted for age and sex.
Model 2 was adjusted for age, sex, body mass index, heart disease, diabetes, eye disease, smoking status, drinking status, taking medication, education level, currently working, living alone, walking speed, exercise habits, depression, and cognitive decline.
Table 4. Association Between Loneliness and Incidence of Disability Among Community-Dwelling Older Adults With Hearing Impairment.
| Variable | Hazard ratio (95% CI) | ||
|---|---|---|---|
| Crude model | Model 1a | Model 2b | |
| Loneliness status | |||
| No loneliness | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Loneliness | 1.82 (1.16-2.86) | 1.89 (1.19-3.00) | 1.71 (1.05-2.81) |
| Potential confounding factors | |||
| Age | NA | 1.17 (1.12-1.21) | 1.14 (1.09-1.19) |
| Female sex | NA | 0.69 (0.44-1.10) | 0.63 (0.31-1.26) |
| Body mass index | NA | NA | 0.98 (0.91-1.06) |
| Has heart disease | NA | NA | 1.15 (0.66-2.00) |
| Has diabetes | NA | NA | 0.95 (0.49-1.84) |
| Has eye disease | NA | NA | 0.97 (0.57-1.63) |
| Current smoker | NA | NA | 1.27 (0.65-2.49) |
| Current drinker | NA | NA | 1.13 (0.68-1.88) |
| Taking medication | NA | NA | 0.99 (0.92-1.08) |
| Education level | NA | NA | 1.12 (1.01-1.24) |
| Currently working | NA | NA | 1.31 (0.69-2.50) |
| Living alone | NA | NA | 0.87 (0.46-1.66) |
| Walking speed | NA | NA | 0.40 (0.01-0.13) |
| Has exercise habits | NA | NA | 1.37 (0.75-2.51) |
| Has depression | NA | NA | 1.52 (0.92-2.51) |
| Has cognitive decline | NA | NA | 1.55 (0.90-2.69) |
Abbreviation: NA, not applicable.
Model 1 was adjusted for age and sex.
Model 2 was adjusted for age, sex, body mass index, heart disease, diabetes, eye disease, smoking status, drinking status, taking medication, education level, currently working, living alone, walking speed, exercise habits, depression, and cognitive decline.
Table 3 summarizes the HRs and 95% CIs in a Cox proportional hazards regression model examining the association between loneliness and the incidence of disability among participants without hearing impairment. In community-dwelling older adults with preserved hearing, no association was found in model 1, adjusted for age and sex (HR, 1.34; 95% CI, 0.98-1.81), and in model 2, adjusted for all potential confounders (HR, 1.10; 95% CI, 0.80-1.52).
Table 4 summarizes the HRs and 95% CIs for the Cox proportional hazards regression model examining the association between loneliness and the incidence of disability among participants with hearing impairment. In community-dwelling older adults with hearing impairment, loneliness was associated with incidence of disability in model 1 (HR, 1.89; 95% CI, 1.19-3.00) and in model 2 (HR, 1.71; 95% CI, 1.04-2.81).
Discussion
In this large cohort study, among community-dwelling older adults with hearing impairment, Cox proportional hazards regression analysis adjusted for relevant confounders showed that loneliness was associated with the incidence of new disabilities. In contrast, among participants without hearing impairment, Cox proportional hazards regression analysis adjusted for relevant confounders showed that loneliness was not associated with the incidence of new disabilities. Previous studies evaluating the association between loneliness and functional disability have revealed mixed findings but have yet to reach a consensus. For example, while an association between loneliness and decreased walking speed,33 as well as decreased ADL ability,34 has been reported, analyses on middle-aged and older adults have found no statistically significant association between loneliness and functional impairment in models adjusted for confounders associated with loneliness.26
It is suggested that loneliness may be the result of several chronic health problems.35 In the interpretation of effect sizes proposed in social science data from previous studies,32 the results in Table 1 indicate that the differences in potential confounders between people with and without hearing impairment are minor. However, as shown in Table 2, the results of the binomial logistic regression analysis with loneliness as the dependent variable indicated that loneliness was associated with a variety of factors, including sex, education level, current job status, living alone, walking speed, exercise habits, hearing impairment, and depression. In particular, a moderate association was found for depression.32 Furthermore, in the present study, Cox proportional hazards regression analysis showed that, after adjustment for relevant confounders, there was no association between loneliness and the incidence of disability for those without hearing impairment. However, there was a statistically significant association between loneliness and the incidence of disability for those with hearing impairment. These results suggest that similar to previous studies, having a hearing impairment is likely to result in a decrease in various activities8 and a narrowing of living space.7 The resulting decrease in social engagement, which may lead to depressive tendencies, and that loneliness may be a factor related to the development of disability. These results support those of previous studies, and this study is, to our knowledge, the first report indicating an association between loneliness and the incidence of disability, stratified by hearing impairment.
Loneliness has been reported to be a common cause of distress among older adults.36,37 Age-related sensory impairments, such as hearing impairment, can foster some sense of discrimination in daily life and consequently increase loneliness among older adults.13 Such loneliness has been reported to be a risk factor for death and worsening health status due to various functional declines.38 Given the high economic costs associated with disability in Japan’s aging population, there is an urgent need to identify contributing risk factors of care and death among older adults and effective interventions. Hearing impairment is recognized as the most relevant modifiable risk factor for dementia,25 which is the leading cause of disability in Japan.39 Efficiently addressing hearing impairment in older adults may be an important measure to reduce the incidence of care needs.
Limitations
Several factors may limit the conclusions obtained from this study. First, this study’s data on hearing impairment was from a questionnaire survey, which has been proven reliable by previous studies20 but lacks data on the duration and history of hearing impairment. Second, participants in this survey were excluded if they were disability impaired at baseline. These exclusion criteria may have resulted in the active selection of healthy older adults rather than older adults in general. Third, there may be other unmeasured factors contributing to the association found in this study, which prevents causal conclusions from being be drawn. However, the results of this study, which revealed the role that the presence or absence of hearing impairment has on the association between loneliness and the incidence of disability, support the hypothesis that loneliness is the result of several chronic health problems and may provide meaningful insights for future measures to prevent loneliness.
Conclusions
This large cohort study showed that older Japanese adults with hearing impairment had a higher incidence of disability than those without hearing impairment. In particular, loneliness was found to be associated with the occurrence of new disabilities among older adults with hearing impairment. Hearing impairment is the most common symptom of geriatric syndromes, showing that among the various risk factors, loneliness may require special attention in the prevention of disability in people with hearing impairment.
Data Sharing Statement
References
- 1.Jafari Z, Kolb BE, Mohajerani MH. Age-related hearing loss and tinnitus, dementia risk, and auditory amplification outcomes. Ageing Res Rev. 2019;56:100963. doi: 10.1016/j.arr.2019.100963 [DOI] [PubMed] [Google Scholar]
- 2.Haile LM, Kamenov K, Briant PS, et al. ; GBD 2019 Hearing Loss Collaborators . Hearing loss prevalence and years lived with disability, 1990-2019: findings from the Global Burden of Disease Study 2019. Lancet. 2021;397(10278):996-1009. doi: 10.1016/S0140-6736(21)00516-X [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Hawkley LC, Kocherginsky M. Transitions in loneliness among older adults: a 5-year follow-up in the National Social Life, Health, and Aging Project. Res Aging. 2018;40(4):365-387. doi: 10.1177/0164027517698965 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Perissinotto CM, Stijacic Cenzer I, Covinsky KE. Loneliness in older persons: a predictor of functional decline and death. Arch Intern Med. 2012;172(14):1078-1083. doi: 10.1001/archinternmed.2012.1993 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Stevenson JS, Clifton L, Kuźma E, Littlejohns TJ. Speech-in-noise hearing impairment is associated with an increased risk of incident dementia in 82,039 UK Biobank participants. Alzheimers Dement. 2022;18(3):445-456. doi: 10.1002/alz.12416 [DOI] [PubMed] [Google Scholar]
- 6.Tomida K, Lee S, Bae S, et al. Association of dual sensory impairment with cognitive decline in older adults. Dement Geriatr Cogn Disord. 2022;51(4):322-330. doi: 10.1159/000525820 [DOI] [PubMed] [Google Scholar]
- 7.Polku H, Mikkola TM, Rantakokko M, et al. Self-reported hearing difficulties and changes in life-space mobility among community-dwelling older adults: a two-year follow-up study. BMC Geriatr. 2015;15:121. doi: 10.1186/s12877-015-0119-8 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Tomida K, Lee S, Bae S, et al. Association of dual sensory impairment with changes in life space: a longitudinal study with two-year follow-up. Maturitas. 2022;165:78-84. doi: 10.1016/j.maturitas.2022.07.017 [DOI] [PubMed] [Google Scholar]
- 9.Dalton DS, Cruickshanks KJ, Klein BE, Klein R, Wiley TL, Nondahl DM. The impact of hearing loss on quality of life in older adults. Gerontologist. 2003;43(5):661-668. doi: 10.1093/geront/43.5.661 [DOI] [PubMed] [Google Scholar]
- 10.Williams N, Guthrie DM, Davidson JGS, Fisher K, Griffith LE. A deterioration in hearing is associated with functional and cognitive impairments, difficulty with communication, and greater health instability. J Appl Gerontol. 2020;39(2):159-171. doi: 10.1177/0733464818755312 [DOI] [PubMed] [Google Scholar]
- 11.Cohen-Mansfield J, Hazan H, Lerman Y, Shalom V. Correlates and predictors of loneliness in older-adults: a review of quantitative results informed by qualitative insights. Int Psychogeriatr. 2016;28(4):557-576. doi: 10.1017/S1041610215001532 [DOI] [PubMed] [Google Scholar]
- 12.Hawkley LC, Cacioppo JT. Loneliness matters: a theoretical and empirical review of consequences and mechanisms. Ann Behav Med. 2010;40(2):218-227. doi: 10.1007/s12160-010-9210-8 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Shakarchi AF, Assi L, Ehrlich JR, Deal JA, Reed NS, Swenor BK. Dual sensory impairment and perceived everyday discrimination in the United States. JAMA Ophthalmol. 2020;138(12):1227-1233. doi: 10.1001/jamaophthalmol.2020.3982 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Uchida Y, Sugiura S, Nishita Y, Saji N, Sone M, Ueda H. Age-related hearing loss and cognitive decline—the potential mechanisms linking the two. Auris Nasus Larynx. 2019;46(1):1-9. doi: 10.1016/j.anl.2018.08.010 [DOI] [PubMed] [Google Scholar]
- 15.Maharani A, Pendleton N, Leroi I. Hearing impairment, loneliness, social isolation, and cognitive function: longitudinal analysis using English Longitudinal Study on Ageing. Am J Geriatr Psychiatry. 2019;27(12):1348-1356. doi: 10.1016/j.jagp.2019.07.010 [DOI] [PubMed] [Google Scholar]
- 16.Liljas AEM, Carvalho LA, Papachristou E, et al. Self-reported hearing impairment and incident frailty in English community-dwelling older adults: a 4-year follow-up study. J Am Geriatr Soc. 2017;65(5):958-965. doi: 10.1111/jgs.14687 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Lin FR, Yaffe K, Xia J, et al. ; Health ABC Study Group . Hearing loss and cognitive decline in older adults. JAMA Intern Med. 2013;173(4):293-299. doi: 10.1001/jamainternmed.2013.1868 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Ciorba A, Bianchini C, Pelucchi S, Pastore A. The impact of hearing loss on the quality of life of elderly adults. Clin Interv Aging. 2012;7:159-163. doi: 10.2147/CIA.S26059 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Yoo M, Kim S, Kim BS, et al. Moderate hearing loss is related with social frailty in a community-dwelling older adults: the Korean Frailty and Aging Cohort Study (KFACS). Arch Gerontol Geriatr. 2019;83:126-130. doi: 10.1016/j.archger.2019.04.004 [DOI] [PubMed] [Google Scholar]
- 20.Lichtenstein MJ. Hearing and visual impairments. Clin Geriatr Med. 1992;8(1):173-182. doi: 10.1016/S0749-0690(18)30505-6 [DOI] [PubMed] [Google Scholar]
- 21.Russell DW. UCLA Loneliness Scale (Version 3): reliability, validity, and factor structure. J Pers Assess. 1996;66(1):20-40. doi: 10.1207/s15327752jpa6601_2 [DOI] [PubMed] [Google Scholar]
- 22.Yuzuri MET, Yuka D. Reliability and validity of the Japanese version of the UCLA loneliness scale version 3 among the older population. Japan Acad Community Health Nurs. 2012;15:25-32. doi: 10.20746/jachn.15.1_25 [DOI] [Google Scholar]
- 23.Arimoto A, Tadaka E. Reliability and validity of Japanese versions of the UCLA loneliness scale version 3 for use among mothers with infants and toddlers: a cross-sectional study. BMC Womens Health. 2019;19(1):105. doi: 10.1186/s12905-019-0792-4 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Tsutsui T, Muramatsu N. Care-needs certification in the long-term care insurance system of Japan. J Am Geriatr Soc. 2005;53(3):522-527. doi: 10.1111/j.1532-5415.2005.53175.x [DOI] [PubMed] [Google Scholar]
- 25.Livingston G, Huntley J, Sommerlad A, et al. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet. 2020;396(10248):413-446. doi: 10.1016/S0140-6736(20)30367-6 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Lund R, Laban J, Petersen GL, Dissing A, Hansen ÅM, Rod NH. Loneliness and objectively measured physical capability in middle-aged adults. Eur J Public Health. 2018;28(1):16-23. doi: 10.1093/eurpub/ckx069 [DOI] [PubMed] [Google Scholar]
- 27.Yesavage JA, Brink TL, Rose TL, et al. Development and validation of a geriatric depression screening scale: a preliminary report. J Psychiatr Res. 1982;17(1):37-49. doi: 10.1016/0022-3956(82)90033-4 [DOI] [PubMed] [Google Scholar]
- 28.Friedman B, Heisel MJ, Delavan RL. Psychometric properties of the 15-item geriatric depression scale in functionally impaired, cognitively intact, community-dwelling elderly primary care patients. J Am Geriatr Soc. 2005;53(9):1570-1576. doi: 10.1111/j.1532-5415.2005.53461.x [DOI] [PubMed] [Google Scholar]
- 29.Tsutsumimoto K, Doi T, Shimada H, et al. Combined effect of slow gait speed and depressive symptoms on incident disability in older adults. J Am Med Dir Assoc. 2016;17(2):123-127. doi: 10.1016/j.jamda.2015.08.012 [DOI] [PubMed] [Google Scholar]
- 30.Folstein MF, Folstein SE, McHugh PR. “Mini-mental state”: a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res. 1975;12(3):189-198. doi: 10.1016/0022-3956(75)90026-6 [DOI] [PubMed] [Google Scholar]
- 31.Tsoi KK, Chan JY, Hirai HW, Wong SY, Kwok TC. Cognitive tests to detect dementia: a systematic review and meta-analysis. JAMA Intern Med. 2015;175(9):1450-1458. doi: 10.1001/jamainternmed.2015.2152 [DOI] [PubMed] [Google Scholar]
- 32.Ferguson CJ. An effect size primer: a guide for clinicians and researchers. Prof Psychol Res Pr. 2009;40(5):532-538. doi: 10.1037/a0015808 [DOI] [Google Scholar]
- 33.Kearns A, Whitley E, Tannahill C, Ellaway A. Loneliness, social relations and health and well-being in deprived communities. Psychol Health Med. 2015;20(3):332-344. doi: 10.1080/13548506.2014.940354 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34.Shankar A, McMunn A, Demakakos P, Hamer M, Steptoe A. Social isolation and loneliness: prospective associations with functional status in older adults. Health Psychol. 2017;36(2):179-187. doi: 10.1037/hea0000437 [DOI] [PubMed] [Google Scholar]
- 35.Guo L, An L, Luo F, Yu B. Social isolation, loneliness and functional disability in Chinese older women and men: a longitudinal study. Age Ageing. 2021;50(4):1222-1228. doi: 10.1093/ageing/afaa271 [DOI] [PubMed] [Google Scholar]
- 36.Shankar A, McMunn A, Banks J, Steptoe A. Loneliness, social isolation, and behavioral and biological health indicators in older adults. Health Psychol. 2011;30(4):377-385. doi: 10.1037/a0022826 [DOI] [PubMed] [Google Scholar]
- 37.Steptoe A, Shankar A, Demakakos P, Wardle J. Social isolation, loneliness, and all-cause mortality in older men and women. Proc Natl Acad Sci U S A. 2013;110(15):5797-5801. doi: 10.1073/pnas.1219686110 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 38.Cummings SM, Neff JA, Husaini BA. Functional impairment as a predictor of depressive symptomatology: the role of race, religiosity, and social support. Health Soc Work. 2003;28(1):23-32. doi: 10.1093/hsw/28.1.23 [DOI] [PubMed] [Google Scholar]
- 39.Summary report of comprehensive survey of living conditions 2019. Japanese Ministry of Health, Labour and Welfare . Accessed February 26, 2023. https://www.mhlw.go.jp/english/database/db-hss/dl/report_gaikyo_2019.pdf
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Sharing Statement