Audiological benefit, quality of life, and factors associated with functional gain in elderly hearing aid users in a developing country between 2017 and 2020: A pre- post-study

doi:10.21203/rs.3.rs-2105680/v1

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Audiological benefit, quality of life, and factors associated with functional gain in elderly hearing aid users in a developing country between 2017 and 2020: A pre- post-study

https://doi.org/10.21203/rs.3.rs-2105680/v1

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published 19 Jun, 2023

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Background: Sensorineural hearing loss (SNHL) is the most common auditory deficit in older adults and may lead to quality-of-life deterioration. However, few studies have been performed in low/middle-income countries, particularly in Latin America. This study aimed to assess the audiological benefit, quality of life, and factors associated with functional gain in elderly hearing aid users in the Fundación Santa Fe de Bogotá and UNIMEQ-ORL, two otology referral centers in Colombia.

Design: Pre-post study that included hearing aid users at the otology consult of the Fundación Santa Fe de Bogotá and UNIMEQ-ORL between June 2017 and December 2020. Glasgow Benefit Inventory (GIB) and Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaires were applied. Audiometric (0,5kHz to 4kHz) and logoaudiometric results were collected.

Results: A total of 75 participants (132 ears) were included. The mean age was 70.73 years (SD: 12.66). The median hearing aid use in years was 0.71 (IQR: 0.64-0.90). Mean change in logoaudiometry was -26.53dB (95%CI: -28.09, -24.97; p<0.001), in functional gain was -21.75dB (-23.81, -19.68; p<0.001). The mean changes in the APHAB domains were Ease of Communication: -37.85 (95%CI: -43.01; -32.7), Background Noise: -3.51 (-6.06; -0.95), and Aversiveness of Sounds: -6.9 (-2.04; 11.77). The GBI assessment of quality of life showed improvement in 100% of the population after the use of hearing aids. The number of years of hearing aids use was associated with functional gain.

Conclusion: The number of years of hearing aids use may impact on the functional gain in these populations. A significant clinical benefit was found in terms of quality of life, communication, and reverberation related to the use of hearing aids. Access to hearing aids should be granted, and public health strategies are needed to grant the access to hearing rehabilitation in these populations.

Trial registration: Fundación Santa Fe de Bogotá (Protocol Number: CCEI-12666-2020)

Hearing aids

Abbreviated Profile of Hearing Aid

Glasgow Benefit Inventory

Quality-of-life.

Hearing loss affects almost 81.4% of adults 80 years or older in the United States (1). Despite this high prevalence of hearing loss among elderly populations, only 15.5–29% of this population reported access to hearing aid or adequate hearing aid usage (1). Thus, the prevalence of hearing loss could show variations between different populations, social variables, and access to hearing aids could also be affected by healthcare barriers and environmental factors in developing countries (2, 3). Early identification of hearing loss followed by an appropriate intervention would reduce its impact on the quality of life (4). In Bogotá, the capital city of Colombia, Cano et al reported a prevalence of hearing loss of 46.1% in adults over 70 years or older, of which only 15% had access to hearing aids (5). However, there is limited data about hearing loss interventions in low- to middle-income countries. Hence, epidemiologic studies are needed to develop public health strategies in these countries.

Hearing impairment has commonly been associated with functional disability, quality of life deterioration, and emotional difficulties (6, 7). In Colombia, a higher prevalence of hearing loss has been described in illiterate adults and in adults who belonged to lower socioeconomic status (5). To date, only one study in an elderly Colombian population has described a significant impairment in the quality of life of adults with hearing loss using the EuroQoL-Visual Analogue Scale, EQ-VAS (5). However, no study has assessed the auditory benefit and changes in the quality of life before and after the adaptation of hearing aid in elderly adults with Sensorineural Hearing Loss (SNHL) in Colombia. Nonetheless, there are few studies in low-income Latin American countries assessing these outcomes. This study aimed to assess the audiological benefit, quality of life, and factors associated with functional gain in hearing aid users with SNHL treated at the Hospital Fundación Santa Fe de Bogotá (FSFB) and UNIMEQ-ORL, Colombia.

Study design

This was an observational, analytical, pre-post study conducted at two otolaryngology referral centers in Bogotá, Colombia: the FSFB and UNIMEQ-ORL, between January 2017 and December 2020. Therefore, this study aimed to assess the possible changes in auditory benefit, quality of life, and factors associated with functional gain in patients with hearing aids. Patients under 70 years old received self-administered written questionnaires, and patients over 70 years old were assessed by their legal tutors to answer the questionnaires. All patients had a clinical diagnosis of sensorineural hearing loss that was supported by logo audiometric results and was performed by an otolaryngologist and an audiologist. The questionnaires were applied during the audiology appointments. According to the Helsinki Declaration, the ethics committee of the FSFB approved this study (CCEI-12666-2020). Informed consent was obtained from all the participants and/or their legal tutors. No incentives were offered for study participation.

Study population

The sample size was calculated based on an average change in the APHAB score in the pretest of -4.9 units with a standard deviation of 12.2 points, a power of 90% (8), and based on the calculation of the size sample shown below (9):

$$n=\frac{2{\left({z}_{1-\alpha }+{z}_{1-\beta }\right)}^{2}}{{\delta }^{2}}+\frac{{z}_{1-\frac{\alpha }{2}}^{2}}{2}$$

Where:

$$\delta =\frac{\left|{\mu }_{z}\right|}{{\sigma }_{z}}=\frac{|{\mu }_{x}-{\mu }_{y}|}{\sqrt{({{\sigma }_{x}^{2}+\sigma }_{y}^{2}-2\rho {\sigma }_{x}{\sigma }_{y})} }$$

And with an exposed / unexposed ratio equal to 1 (r = 1), the sample size is equal to 75 subjects. Regarding the sample selection method, a non-probabilistic, consecutive sampling was conducted.

Questionnaires and tools

The Glasgow Benefit Inventory (GIB) scale was applied to the population study one year after hearing aids indication to assess the quality of life. This scale is sensitive to changes related to otolaryngological interventions. The GBI has 18 questions and 3 domains: 12 questions assess the change in “General benefit”, 3 questions assess “Physical benefit”, and 3 questions are related to the “Social support changes”. It gives a score of -100 (negative benefit), 0 (no benefit), and + 100 (positive benefit) (10). On the other hand, the Abbreviated Profile of Hearing Aid Benefit (APHAB) is a self-assessment disease-specific disability questionnaire with 24 items divided into four 6-item subscales. The APHAB questionnaire allows patients to measure difficulties with speech or noises in various everyday environments: ease of communication (EC), listening under reverberant conditions (RV), listening in background noise (BN), and the aversiveness of sounds (AV). The responses can be scored on a 7-point scale. Both, the GBI and APHAB questionnaires are widely accepted and internationally validated instruments.

Statistical analysis

Statistical analysis was performed using Stata 16MP software. The descriptive analysis calculated absolute and relative frequencies for the qualitative variables. Measures of central tendency (mean and median) were estimated for the quantitative variables. Standard deviation (SD) and interquartile range (IQR) were assessed for the dispersion measures. A “change from baseline” measure in audiometry values and APHAB domains was calculated using the differences between the baseline scores obtained before using the hearing aid and the scores after one year. A bivariate and multivariate analysis between pre and post-measurement data of these scores were analyzed by the paired samples Wilcoxon test. A GEE analysis using an unstructured correlation matrix was carried out to assess the effect of the functional gain after use and fitting of a hearing aid for one year. This effect was adjusted considering the clinical and demographic variables with clinical relevance or biological plausibility, and those with a P-value ≤ 0.2 in ANOVA/Friedman test. Model assumptions were validated through a linearity test, an estimation of standardized residuals and leverage values, and a comparison between the crude and the adjusted models. Hypothesis testing to determine the level of statistical significance was performed using a 95% confidence interval and a P-value < 0.05.

A total of 75 individuals were included, with a mean age of 70.73 year (SD: 12.66 year), 54.67% (n = 41) were female, and 84% were aged over 60 years old. The baseline demographic and clinical characteristics of the study population are described in Table 1. The mean hearing aid usage time in years was 0.82 (SD:0.48). The frequency of hearing aid brands was: Widex 58.67%, Phonak 34.67%, Starkey 4%, and RESound/AOR 2.67%, respectively.

Table 1

Baseline clinical and sociodemographic characteristics of the study population
Variables	Total participants (n = 75)
Variables	n	%
Sex: Female/Male	41/34	54.67/45.33
Age in years ^(a)	70.73 (12.66)	72.42 (65.19–80.03)
Age group		261
40 years old or less	3	4.00
40 to 60 years-old	9	12.00
60 years old or more	63	84.00
Hearing aid usage time in years ^(a)	0.82 (0.48)	0.71 (0.64–0.90)
Hearing aid brand
Widex	44	58.67
Phonak	26	34.67
Starkey	3	4.00
RESound/AOR	2	2.67
GBI score post-test ^(b.c)
General benefit	42 (33–50)
Social support	50 (50–67)
Physical health	17 (17–33)
Total GBI	39 (17–47)
Improvement in General benefit ^(d)	75	100.00
Improvement in Social support ^(d)	74	98.67
Improvement in Physical health ^(d)	67	89.33
Improvement in total GBI ^(d)	75	100.00
a. ^{Values reported in Means (SD) and Medians (IQR)}
b. ^{GBI subscales}
c. ^{Values reported in Medians (IQR: p25-p75)}
d. ^{Corresponds to the number of subjects and percentage of the population with improvement by respective subscale}

Changes in audiological outcomes

In terms of audiometric values, the changes for 0.25kHz, 0.5kHz, 1kHz, 2Khz, 3kHz and 4kHz were: -13.03dB (95% CI: -15.8; -10.26), -15.3dB (-18.03; -12.57), -19.05dB (-21.55; -16.55), -22.65dB (-24.81; -20.49), -24.79db (-26.87; -22.72), and − 26.93dB (-29.19; -24.68), respectively (Table 2 and Fig. 1). All these values were statistically significant. The change in the discrimination percentage of the logo-audiometry was 4.2% (2.73;5.66), while the mean change in the logo-audiometry values was − 26.53dB (-28.09; -24.97).

Table 2

Pre and post APHAB comparison and audiometric results
Variables	Pre-test values	Post-test values	Mean change (post - pre)	p
Variables	Mean (SD)	Mean (SD)	Mean (95%CI)	p
APHAB score (n = 75)
EC	54.3 (21.7)	16.5 (10.1)	-37.85 (-43.01; -32.7)	< 0.0001
RV	50.9 (8.18)	50.3 (8.93)	-0.6 (-3.64; 2.44)	0.46
BN	51.7 (8.37)	48.2 (8.16)	-3.51 (-6.06; -0.95)	0.004
AV	31.9 (17.2)	38.8 (18.1)	-6.9 (-2.04; -11.77)	0.007
Discrimination percentage logo audiometry	95.67 (6.89)	99.87 (1.16)	4.2 (2.73; 5.66)	< 0.0001
dB logo audiometry	80.2 (7.09)	53.67 (8.56)	-26.53 (-28.09; -24.97)	< 0.0001
AC values (n = 132 ^(a))
0.25 kHz	33.8 (17.4)	20.8 (6.1)	-13.03 (-15.8; -10.26)	< 0.0001
0.5 kHz	37.7 (17)	22.4 (5.26)	-15.3 (-18.03; -12.57)	< 0.0001
1kHz	44.5 (15.5)	25.4 (6.27)	-19.05 (-21.55; -16.55)	< 0.0001
2kHz	51.1 (12.3)	28.5 (5.09)	-22.65 (-24.81; -20.49)	< 0.0001
3kHz	54.5 (11.9)	29.7 (4.98)	-24.79 (-26.87; -22.72)	< 0.0001
4kHz	57.9 (12.9)	31 (5.51)	-26.93 (-29.19; -24.68)	< 0.0001
Functional gain in dB	49.16 (12.45)	27.41 (4.716)	-21.75 (-23.81; -19.68)	< 0.0001
a. ^{67 right ear and 65 left ears analyze}
b. ^{Based on a paired samples Wilcoxon test}

Quality of life

Table 1 shows the results for GBI scores for a total median domain with 39 points (IQR:17–47), median general benefit of 25 points (IQR:33–50), median social support of 50 points (IQR:50–67), and median physical health of 17 points (IQR:17–33), respectively. Thus, 100% of the participants reported improvement in the total GBI score; 100% reported improvement in the general benefit subscale, 98.67% reported improvement in social support, and 89.33% an improvement in physical health (Table 1).

Table 2 shows APHAB scores mean (SD) and median (IQR), discrimination percentage logo audiometry, logo audiometry results, and Air Conduction values audiometry before and after intervention in addition to pre-post differences. The crude means differences and confidence intervals of APHAB scores were EC: -37.85 (95%CI: -43.01; -32.7), BN: -3.51 (-6.06; -0.95), and AV: -6.9 (-2.04; -11.77), respectively. These changes in the scores were statistically significant.

Factors associated with functional gain

Table 3 shows the bivariate and multivariate analyses of the sociodemographic variables for the hearing aids treatment and its effect on audiological benefit. The multivariate and reduced models showed a mean change from baseline in functional gain values of -21.75dB (0.25;0.97) adjusted by sex, age, laterality of the hearing loss, and time of use of hearing aids. These results are consistent with the raw comparisons shown in Table 2 which showed a similar reduction in functional gain in the study population. No collinearity problems were found in the models through the linearity and the goodness-of-fit tests. Overall, these assessments showed good model specifications, and the residual outliers or leverage values did not disturb the models.

Table 3

Impact of sex, age, and changes in functional gain: GEE model
Variable ^(a)	Functional gain
	Bivariate model			Multivariate model			Reduced model ^(b)
	Coeff.	95% CI		Coeff.	95% CI		Coeff.	95% CI
Time
First assessment	0	baseline		0	baseline		0	baseline
Final assessment	-21.75	-23.68	-19.81	-21.75	-23.68	-19.81	-21.75	-23.69	-19.80
Laterality
Right ear	0	baseline		0	baseline		--	--	--
Left ear	0.71	-2.87	4.28	0.48	-1.51	2.48	--	--	--
Sex
Male	0	baseline		0	baseline		0	baseline
Female	-21.80	-51.11	0.75	-1.57	-4.50	1.36	-1.80	-4.72	1.13
Age	-0.07	-0.18	0.045	-0.06	-0.18	0.050	--	--	--
Time use of hearing aids	-1.01	-3.97	1.95	-1.40	-4.37	1.58	--	--	--
Constant	38.18	36.70	39.66	55.68	47.04	64.32	50.33	47.94	52.71
a. ^{Bolded numbers highlight the significant associations between the variables}
b. ^{The reduced model was based on the Furnival−Wilson leaps−and−bounds algorithm. GEE model was estimated with an exchangeable matrix correlation}

Despite hearing aids having wide scientific evidence to improve functional disability and quality of life deterioration related to hearing loss in elderly populations, few studies have assessed these benefits in low/middle-income Latin American countries. This study described the audiological benefit and changes in patients' quality of life in older patients with SNHL treated with hearing aids in a low/middle-income Latin American country. Regarding the audiometric values, an improvement of at least 13 dB was found for the speech frequencies (250–4000 Hz). Similarly, a prior study reported an improvement up to 7 dB +/- 16 dB for the mean pure-tone average at speech frequencies using bone-anchored hearing aids (BAHA) (11). These findings were also supported by the logo-audiometric values that showed significant improvement in the speaking discrimination of words at lower dB values.

To gain insight into the quality-of-life changes of this population, the main domains of the GBI score were assessed (general benefit, physical benefit, and social support changes). Overall, the results for GBI scores showed a significant benefit for all the domains of the scale, and up to 100% of the participants reported an improvement in the total GBI score. These findings are similar to a prior study among 134 older patients who received BAHA for SNHL in the Netherlands that reported positive GBI scores in 84% of the population, and a general satisfaction reported by 71% of the population (de Wolf et al., 2010). Likewise, applying the APHAB questionnaire, the scores showed statistically significant changes in the domains of communication, noise, and aversiveness. We highlight that the higher change was found for the EC domain (-37.85; -43.01, -32.7). Similarly, using the APHAB to assess the changes in quality of life, De Wolf et al described that among 134 older users of BAHA, 80% of the population reported a significant reduction in their daily problems, and the best scores were obtained for the EC subscale (11). Our results were similar to these previous findings, and we stand out that hearing aids improve communication with others, which was described as the most important change for the patients.

In terms of the BN (-3.51; -6.06; -0.95), and AV (-6.9; -2.04; -11.77) domains, our population reported less favorable results. Thus, these findings could be explained by differences in hearing aids brands, and access to maintenance of the hearing aids. Prior authors have also reported these differences in elderly hearing aid users (11, 12). On the other hand, the multivariate and reduced models showed a change of -21.75 dB on functional gain between pre and post audiometric assessments (95% CI: -23.69; -19.80). This scenario could be explained by a longer period of hearing aid use related to advanced handling and higher experience in the maintenance of hearing aids. Hickson et al described five factors associated with higher success in hearing aids in older adults: greater social support; more difficulties with hearing and communication in everyday life before getting hearing aids; more positive attitudes to hearing aids; greater perceived self-efficacy for advanced handling of hearing aids; or who were receiving more gain from their devices (13).

Overall, these findings highlight the importance of addressing sociodemographic factors to support older adults in achieving success with hearing aids. Finally, we stand out that prior studies have described difficulties in reaching otolaryngology specialists in low/middle-income Latin American countries (14, 15), and additional strategies are needed to grant hearing aid access to older populations in these countries. Access to hearing aids should be granted, and public health strategies are needed to grant the access to hearing rehabilitation in these populations.

Among the strengths of the study, we highlight that the questionnaires were developed by one otolaryngologist and one audiologist with wide clinical experience, and the sociodemographic information was obtained by trained professionals to minimize measurement bias. Moreover, the otolaryngologist of this study reviewed all the information about outcomes and audiological treatment. We highlight that the intensity of audiological change and quality of life were assessed through validated scales in these constructs, so reporter bias and overestimation of the possible benefits in these outcomes were reduced (16). Moreover, the initial and follow-up audiometric studies were performed in the same audiological center, which would reduce the heterogeneity between different audiometric centers and equipment.

About the limitations of the study, we stand out the cross-sectional design of this study which would also lead to recall bias, considering that most hearing aid patients had to recall their benefit compared to several years ago. However, we also stand out that the most accurate way to evaluate health-related quality of life is to administer the questionnaires before hearing aid fitting and to repeat these measurements after a certain interval which would avoid recall bias (11). We followed these recommendations and applied the questionnaires before and after hearing aid fitting. Moreover, a higher sample size could improve the generalization of these results. Further studies in these populations are needed.

A significant clinical benefit was found in terms of audiological benefit, communication, reverberation, and quality of life probably due to the use of hearing aids.

Ethics approval and consent to participate

The Ethical Committee of the Fundación Santa Fe de Bogotá (Protocol Number: CCEI-12666-2020) approved this study. All patients provided written informed consent.

Consent for publication

Not applicable.

Availability of data and materials

Part of the data generated or analyzed during this study is included in this published article. Full datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Competing interests

The authors report no conflicts of interest. The authors are responsible for the content and writing of the paper.

Funding

This study was supported by the Unidad Medico Quirúrgica de Otorrinolaringología UNIMEQ-ORL from Bogotá, Colombia.

Authors’ contributions

Conceptualization: AP, DH, LCP. Data evidence collection: LCP, LN, DH. Supervision: AP. Statistical analysis and methodology: SML. Data analysis: AP, DP, DH, DM, SML, LCP. Funding acquisition and resource provision: AP. Writing – Original Draft Preparation: AP, DP, DM, SML, LCP. Writing – Review & Editing: AP, DP, DH, DM, SML, LCP, LN.

Acknowledgments

An abstract and poster of this article were presented in 2022 in the “AAO-HNSF 2022 Annual Meeting & OTO Experience” of the American Academy of Otolaryngology, and the abstract of this manuscript will be published in the supplementary issue of the journal “Otolaryngology–Head and Neck Surgery”. Special thanks to Gloria Corredor-Rojas who supported the fieldwork of this study.

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No competing interests reported.

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You are reading this latest preprint version

Audiological benefit, quality of life, and factors associated with functional gain in elderly hearing aid users in a developing country between 2017 and 2020: A pre- post-study

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Abstract

Figures

Introduction

Methods

Study design

Study population

Questionnaires and tools

Statistical analysis

Results

Changes in audiological outcomes

Quality of life

Factors associated with functional gain

Discussion

Conclusion

Declarations

References

Additional Declarations

Status:

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