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 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 22  |  Issue : 4  |  Page : 228-232

Validation of hearing handicap inventory for the elderly questionnaire among elderly subjects in Sagamu, Nigeria


From the ENT Unit, Department of Surgery, College of Health Sciences, Olabisi Onabanjo University, Sagamu, Nigeria

Date of Web Publication14-Jan-2016

Correspondence Address:
Olusola Ayodele Sogebi
From the ENT Unit, Department of Surgery, College of Health Sciences, Olabisi Onabanjo University, Sagamu
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1117-1936.173974

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  Abstract 

Background: Use of hearing impairment (HI) questionnaires has been an alternative to formal audiometry.
Objective: To validate hearing handicap inventory for the elderly (HHIE) questionnaire and verify its suitability or otherwise as a screening instrument in low-resource clinical settings.
Subjects and Methods: A cross-sectional analytical study deployed the HHIE questionnaire to detect emotional and situational hearing handicaps (HHs) and assigned scores. Total scores were categorised as no, mild to moderate or significant HH. Pure tone audiometries (PTAs) were performed and PT average (PTAv) was calculated. HHIE scores were compared with the PTAvs. Validity of HHIE scores compared with PTAvs was explored with sensitivity, specificity and predictive values, while correlation coefficients combined age, HHIE scores and PTAv. Level of statistical significance was taken as P < 0.05 for all analyses.
Results: One hundred and three subjects with mean age ± standard deviation, 71.3 ± 7.2 years were studied. Over 70% (71.8%, 74/103) were married, 63.1% (65/103) attended secondary school, 35.0% (36/103) were professionals and 45.6% (47/103) were retired. HHIE questionnaire revealed 59.2% (61/103) had handicap and PTA confirmed 47.6% (49/103) had HI. Comparing HHIE scores with PTAv, overall sensitivity was 79.6%, specificity was 59.3%, positive predictive value was 63.9% and negative predictive value was 76.2%. HHIE scores correlated significantly with PTAv (r = 0.527, P < 0.001) and there was no correlation between age and PTAv (r = 0.145, P = 0.143) and between age and HHIE scores (r = 0.187, P = 0.059).
Conclusion: HHIE scores obtained from questionnaire can adequately quantify HI. HHIE questionnaire is a valid screening instrument to identify HH among elderly subjects.

Keywords: Audiometry, elderly, hearing handicap inventory for the elderly, hearing impairment, presbycusis


How to cite this article:
Sogebi OA, Mabifah TO. Validation of hearing handicap inventory for the elderly questionnaire among elderly subjects in Sagamu, Nigeria. Niger Postgrad Med J 2015;22:228-32

How to cite this URL:
Sogebi OA, Mabifah TO. Validation of hearing handicap inventory for the elderly questionnaire among elderly subjects in Sagamu, Nigeria. Niger Postgrad Med J [serial online] 2015 [cited 2019 Mar 26];22:228-32. Available from: http://www.npmj.org/text.asp?2015/22/4/228/173974


  Introduction Top


Hearing impairment (HI) has remained a notable morbidity factor among elderly subjects. Its incidence is expected to increase geometrically with an increase in life expectancy. [1] Presbycusis is the most common form of HI and communicative disorder encountered in the older adult populations. [2] Prevalence of presbycusis among elderly Nigerians range between 22.7% and 38.2% and it is projected to increase within the next decade. [3],[4] Presbycusis is associated with morbidities, which compounds several other health challenges encountered by the elderly. It also negatively impacts the functional ability and capabilities of elderly subjects. [5] Some cases of presbycusis, however, remain undiagnosed.

Hindrances to diagnosis include lack of public awareness among elderly subjects who live in the communities. Many elderly subjects live in the rural areas and have no access to required health care facilities. [6] Pure tone audiometry (PTA) remains the simplest means of assessing hearing levels in adult and elderly subjects. Scarcity of well-calibrated audiometer and appropriate sound-proof facilities are hurdles to the provision of regular hearing assessments. [7] Furthermore, there is dearth of competent audiologists to perform such assessments in developing countries. Thus, alternative means to audiological assessment of HI had been deployed to resolve these peculiar problems. Methods such as self-report, [8] personal self-assessment of HI and questionnaires such as hearing handicap inventory for the elderly (HHIE) questionnaires [9] were developed for use in audiological research. Some of the questionnaires have even been translated into local languages and more recently, on-line versions have been introduced. [10],[11]

The HHIE questionnaire was developed by Weinstein and Ventry in 1982. [12] It assesses emotional and situational handicaps resulting from HI among elderly subjects as an indirect way of quantifying the degree of HI. It has gained widespread application and use because it is available in many languages with cross-cultural adaptation, it may be completed within minutes, it is effective at assessing the handicap effect of HI on subjects' everyday function and may identify individuals who are more likely to accept intervention. [13]

The HHIE has thus been validated as a screening tool and adapted in clinical situations in many countries in Europe, America and Asia. [13],[14],[15] It was incorporated for use in community-based studies among the elderly, especially in inaccessible rural areas in such developed countries. [13],[14] Its use in developing countries particularly among native Africans where there are limited audiological facilities for diagnosis and management of HI has however been sparse or sparsely reported. [7] In fact, literature search did not produce any previous use or validation of this questionnaire among Nigerians.

This study therefore aims to assess the proportion of elderly patients with handicaps resulting from HI using the HHIE questionnaire and comparing this with audiometric-measured hearing thresholds. This is with the view of validating the questionnaire and verifying its suitability, adaptability or otherwise as an instrument at the community level and in resource-limited clinical settings.


  Subjects and Methods Top


This cross-sectional analytical study was conducted between January and October 2015 at Olabisi Onabanjo University Teaching Hospital (OOUTH), Sagamu, Nigeria. The study participants were elderly subjects who attended the ear, nose and throat clinics of the hospital. An elderly subject was defined as one aged 60 years or above. Sample size was determined based on the clinic attendance statistics on average number of new patients that attended the clinics par year (587) in the previous 5 years, 15.7% of which were elderly (92 patients). An attrition rate of 10% was added to give a minimum sample size of 101 subjects. Consecutive elderly subjects who met the inclusion criteria were approached and sampled for consent.

The purpose of the study and its importance were explained to the subjects and those who consented had their ears examined, with particular emphases on the condition of the external auditory canals and tympanic membranes on otoscopy. Eligible subjects were those with clear external auditory canals and intact tympanic membranes in both ears.

Thereafter, sociodemographic and clinical information were obtained and HHIE questionnaire were administered on the subjects. The HHIE questionnaire used for this study was the face validated version, but adapted to the local setting by translating the questions into Yoruba language (the local language for communication in the study centre). The questions were screened by an audiologist for internal consistency and questionnaire was pre-tested on elderly patients at the general out-patients clinics at the State Hospital, Abeokuta, Nigeria. The eligible subjects subsequently had hearing assessments by performing formal PTA in both ears. Subjects excluded were those with significant pathologies in the external ears such as otitis externa, those with perforated tympanic membranes and clinical evidence of middle ear disease. Subjects who did not perform the PTA were also excluded. The study protocol was approved by the Health Research and Ethics Committee of OOUTH, Sagamu, Nigeria; approval number OOUTH/DA.326/T/197.

The HHIE questionnaire assessed the presence of perceived emotional and situational hearing handicaps (HHs), by asking specific questions in each section and attaching scores to each response, required yes (4), sometimes (2) and no (0). Scores for all questions were collated and added to produce the final scores (maximum 100). Based on the final score, HH was categorised thus; no handicap (0-16), mild to moderate handicap (17-42) and significant handicap (≥43). PTA was performed in a sound-proof booth, using a calibrated diagnostic audiometer GSI 67, with hearing thresholds assessed for the air-conduction from 0.25 to 8.0 kHz and for bone conduction from 0.25 to 4.0 kHz frequencies, in each of the ears separately. The hearing thresholds were subsequently plotted to obtain the pure tone audiographs. The PT averages (PTAvs) were calculated as the arithmetic mean for the hearing thresholds for the air-conduction for all the measured frequencies in the two ears, and the hearing level for each patient was taken as the PTAv in the better-hearing ear. The HH levels based on scores in the HHIE questionnaire should be comparable to the level of impairment based on the audiometric measured hearing thresholds.

Thirteen subjects that had wax impaction had such extracted before proceeding to do the PTA. All the information i.e., clinical, HHIE scores and audiometry parameters obtained were entered into a spread sheet and analysed using statistical packages for social sciences SPSS version 20 (Chicago, Illinois, USA). The information was presented as descriptive and analytical data in tables. Discrete variables were presented as proportions (percentages) whereas continuous variables were presented as means with their dispersions (standard deviations [SDs]). Total HHIE scores of at least 17 defined HH and this cut-off point was used in validating the HHIE instrument against the audiometric-measured hearing thresholds in the ears. Comparative analyses exploring differences between discrete variables were done using Chi-square tests, and those for continuous variables were explored using independent sample t-tests. Usefulness of the HHIE parameters compared with that of pure tone audiograms were explored with sensitivity, specificity and predictive values. Correlation coefficients combining age, HHIE scores and PTAv scores were also explored, using Pearson product moment correlation coefficient for age with PTAv, Spearman rank for age with HHIE scores and HHIE scores with PTAv. Level of statistical significance was taken as P < 0.05 for all analyses.


  Results Top


One hundred and three elderly subjects participated fully in the study and had their data analysed. This consisted of 54 males and 49 females, male:female = 1.1:1 with age ranging between 60 and 92 years, mean ± SD, 71.3 ± 7.2 years. Over 70% (71.8%, 74/103) of the subjects were married and 63.1% (65/103) had at least secondary school education. Thirty-five percent (35.0%, 36/103) had some skills or were professionals whereas 45.6% (47/103) were retired. There were significant differences in the marital status, level of education and occupational category between the male and female elderly subjects as detailed in [Table 1].
Table 1: Sociodemographic characteristics of 103 subjects according to sex

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Assessment of the handicap experienced with hearing loss in the subjects using the HHIE questionnaire revealed that 59.2% (61/103) of the subjects had some level of handicap associated with their hearing losses. PTA discovered that 47.6% (49/103) had audiometric-confirmed HI. The hearing assessment parameters of the subjects are shown in [Table 2].
Table 2: Hearing assessment parameters of the subjects (n=103)

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[Table 3] is the comparison of the parameters of HHIE with those of the PTAv, overall sensitivity was 79.6%, specificity was 59.3%, positive predictive value (probability that the questionnaire will correctly detect subjects with HI) was 63.9% and negative predictive value (probability that the questionnaire will correctly detect subjects without HI) was 76.2%. The specific screening for HHIE values for audiometric-assessed values depicting no, mild-moderate and significant impairment was also detailed.
Table 3: Screening characteristics of hearing handicap inventory for the elderly against standard audiometric values

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[Table 4] explored the correlations between different parameters in the subjects. There was a weak but significant correlation of HHIE scores with PTAv (r = 0.527, P < 0.001) of the subjects, whereas there were no correlations of age with HHIE scores (r = 0.187, P = 0.059) and age with PTAv (r = 0.145, P = 0.143) of the subjects.
Table 4: Correlation parameters of the factors

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  Discussion Top


This study explored the suitability of the HHIE questionnaire as an alternative to performing formal PTA to assess hearing level and impairments among elderly subjects. Despite even distribution of age and sex of the subjects, significant gender-related differences in social and marital parameters were observed in this study. Staehelin et al. reported gender-specific factors that influenced social behaviours in hearing-impaired elderly patients using hearing aids in Switzerland. [16] Being widowed was also found to be a non-audiologically associated factor with self-perceived HH. [17]

PTA confirmed HI in 47.6% of the subjects, majority of which were of the mild magnitude. Regardless of magnitude, the effect of hearing loss may be significant enough to affect individual's functioning beyond the measured thresholds on an audiometric scale. Furthermore, subjectivity of the PTA and its sensitivity may affect its accuracy and subtly down-scale the HI. HI may also be masked by other factors, especially tinnitus and there might be associated recruitment of sounds. However, 9.7% of our subjects had significant HI by audiometric assessment. Lasisi et al. used a text phrase to assess significant HI in elderly subjects in the Ibadan study on ageing and reported a prevalence of 6.1%. [18] The comparatively higher value reported in the present study might have been due to employing a questionnaire that assessed different parameters, which was used in a hospital setting and the smaller sample size having a tendency to exaggerate prevalence rates.

Juxtaposing measured PTAv levels with HHIE scores to assess HI and its handicap level revealed that actually 59.2% of the elderly subjects had some handicap, compared to 47.6% with audiometric-confirmed HI. Screening approaches try to increase the likelihood a person with a specific dysfunction has to be identified (sensitivity), excluding those without the dysfunction (specificity). [19] In practice during hearing assessment, there might be some patients who although have some measure of hearing dysfunction, had not reached the specific criteria set for such by audiometry. [9] It must also be noted that the audiometric PTAv values recorded were those for the better-hearing ear which may be responsible for the lower prevalence of HI using PTAv compared to impairment levels from HHIE questionnaire. In studies comparing self-report of hearing loss to PTA, the use of the better-hearing ear is justified by the fact that the worse ear tends to be compensated by the function of the side that has better subjective perception. [20] Other authors had attributed subjective hearing difficulties without audiometric diagnosed impairment to reflect psychosocial problems experienced in daily communication situations. [8] HI is a serious problem and leads to significant handicap among elderly subjects affecting daily living activities, especially in the social, emotional and cognitive domain with a tendency to depression in elderly Africans. [21]

The HHIE questionnaire appears to be a good screening instrument among our subjects with reasonable screening parameters when compared with the standard audiometric values. Overall sensitivity was 79.6% and specificity was 59.3%, with reasonable predictive values. Both the complete HHIE and its shorter form HHIE screening version (HHIE-S) have been validated in different places all over the world since it was first introduced over three decades ago. Although the sensitivity values had been variable and ranged between 69.0% and 100.0% in different studies, [9],[19],[22] most studies had confirmed its usefulness. It was thereafter adopted as a reasonably sensitive instrument that could be deployed in epidemiological and population-based studies to assess HI and its associated handicap among elderly subjects. The general specificity value of 59.3% obtained in our study was marginally over the values of between 43.5% and 58.5% for HHIE obtained at different audiometric averages in the study done in Brazil. [23] To detect significant hearing loss (i.e., PTAv >40 dB HL), the HHIE of ≥43 had both greater sensitivity (95.3%) and specificity (91.4%). Some other studies had earlier reported similar findings; [10],[19] Diao et al. compared self-reported hearing and measured hearing thresholds among elderly subjects in China and reported that at PTAv >40 dB measured at frequencies 0.5-4 kHz, the self-reported hearing had a sensitivity of 100% and a specificity of 84.5%. [10]

HI in the elderly should be regarded a serious health challenge requiring attention. Some studies had found subtle differences in the sensitivity parameters at different age grades. Sindhusake et al. in the Blue Mountains hearing study in Australia found that the HHIE-S performed slightly better in younger than older subjects. [19] Some authors had explained the greater sensitivity found in the younger group to be due to low self-perception or denial of problems faced by the elderly. [24] In view of the popular belief that hearing loss is a normal process of ageing and not a health problem deserving special attention, [25] elderly subjects tend to underrate their auditory difficulty. [26] Although this study did not compare the sensitivity of instrument according to age stratification, it is reasonable to submit that with the parameters obtained, HHIE has proved to be a useful instrument that could be adopted for use in the elderly subjects in sub-Saharan Africa, particularly in Nigeria.

The finding of a weak but significant correlation between HHIE scores and the PTAv was notable and may further buttress the validity and usefulness of the index questionnaire. Other studies had also confirmed correlation of pure tone sensitivity with the HHIE scores, [12] being more frequent in subjects with moderately-severe hearing loss than among those with mild loss. [24],[27] While the HHIE questionnaire has a propensity to assess hearing in both ears simultaneously, natural inclination was for subjects to respond to questions based on their perception in the worse hearing ear. On the contrary, audiometrically measured hearing levels (PTAv) utilised measurements in the better-hearing ear. This might lead to subtle disparity between the two measures and might have been responsible for the weak correlation coefficient observed in this study between the HHIE scores and PTAv parameters.

There was however, no correlation of age with HHIE scores and also with PTAv in this study. Ageing is a natural and presumably irreversible process, manifesting with global degeneration of tissues and organs. [28] The sensory organs, especially hair cells of the cochlea are particularly vulnerable to degenerative changes, manifesting as HI, which can be handicapping. [1] This degeneration seems to progress as age advances. Level of hearing may not be dependent on the degenerative processes resulting from ageing alone. Other confounding factors including genetic factors and environmental exposure, diseases, occupation and medications also interfere with hearing perception. Thus, exposure to noise, significant loud noise, ototoxic medications, ear infections and acoustic traumas of various types all make contributions. It is the integration of all these contributions with age that will actually determine the hearing level of elderly subjects. Unfortunately, some of these confounding factors were not screened nor controlled in this study, thus constituting a limitation to the study. The other limitations inherent in the study included the fact that questionnaires were administered on the subjects on an 'once and for all bases', with subjects being prone to recall bias, absence of clarification from a third party such as spouse, relative or close associates, to corroborate or refute the response of the subjects.


  Conclusion Top


The HHIE questionnaire was adjudged to be sufficiently sensitive and specific to provide estimates of hearing loss in elderly subjects. It is a reasonably valid screening instrument to recommend for use in community epidemiological studies and in places where formal audiometry cannot be performed readily in Nigeria.

Acknowledgements

The authors wish to acknowledge the medical officers at the State Hospital, Abeokuta, Nigeria, for their assistance in sourcing the patients that were used for pre-testing the questionnaires for this study in their hospital.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]


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