Prevalence of Hearing Impairment in a Rural Midwestern Cohort: Estimates from the Keokuk County Rural Health Study, 1994 to 1998

Rural Otolaryngology Care Disparities: A Scoping Review

OBJECTIVE

To broadly synthesize the literature regarding rural health disparities in otolaryngology, categorize findings, and identify research gaps to stimulate future work.

STUDY DESIGN

Scoping review.

DATA SOURCES

A comprehensive literature search was performed in the following databases: PubMed/MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Google Scholar, and CINAHL.

REVIEW METHODS

The methods were developed in concordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. Peer-reviewed, English-language, US-based studies examining a rural disparity in otolaryngology-related disease incidence, prevalence, diagnosis, treatment, or outcome were included. Descriptive studies, commentaries, reviews, and letters to the editor were excluded. Studies published prior to 1980 were excluded.

RESULTS

The literature search resulted in 1536 unique abstracts and yielded 79 studies that met final criteria for inclusion. Seventy-five percent were published after 2010. The distribution of literature was as follows: otology (34.2%), head and neck cancer (20.3%), endocrine surgery (13.9%), rhinology and allergy (8.9%), trauma (5.1%), laryngology (3.8%), other pediatrics (2.5%), and adult sleep (1.3%). Studies on otolaryngology health care systems also accounted for 10.1%. The most common topics studied were practice patterns (41%) and epidemiology (27%), while the Southeast (47%) was the most common US region represented, and database study (42%) was the most common study design.

CONCLUSION

Overall, there was low-quality evidence with large gaps in the literature in all subspecialties, most notably facial plastic surgery, laryngology, adult sleep, and pediatrics. Importantly, there were few studies on intervention and zero studies on resident exposure to rural populations, which will be critical to making rural otolaryngology care more equitable in the future.

Prevalence of childhood hearing impairment of different severities in urban and rural areas: a nationwide population-based study in Taiwan

OBJECTIVE

Childhood hearing impairment (CHI) is a major developmental disability, but data at the national level are limited, especially those on different severities. We conducted a study to fill this data gap.

DESIGN

A nationwide study on the basis of a reporting system.

SETTING

To provide services to disabled citizens, the Taiwanese government maintains a registry of certified cases. Using data from this registry, we estimated prevalence rates of CHI of different severities from 2004 to 2010 and made comparisons between urban and rural areas.

PARTICIPANTS

Taiwanese citizens ≤17 years old.

PRIMARY OUTCOME MEASURES

To qualify for CHI disability benefits, a child must have an unaided pure-tone better ear hearing level at 0.5, 1 and 2 kHz with an average ≥55 decibels (dB), confirmed by an otolaryngologist. The severity was classified by pure-tone better ear hearing level as mild (55-69 dB), moderate (70-89 dB) and severe (≥90 dB).

RESULTS

The registered cases under 17 years old decreased annually from 4075 in 2004 to 3533 in 2010, but changes in the prevalence rate were small, ranging from 7.62/10 000 in 2004 to 7.91/10 000 in 2006. The prevalence rates of mild CHI increased in all areas over time, but not those of moderate or severe CHI. Rural areas had higher overall prevalence rates than urban areas in all years, with rate ratios (RRs) between 1.01 and 1.09. By severity, rural areas had higher prevalence rates of mild (RRs between 1.08 and 1.25) and moderate (RRs between 1.06 and 1.21) CHI but had lower prevalence rates of severe CHI (RRs between 0.92 and 0.99).

CONCLUSION

While rural areas had higher overall prevalence rates of CHI than urban areas, the RRs decreased with CHI severity. Further studies that identify factors affecting the rural-urban difference might help the prevention of CHI.

Audiological Assessment of Word Recognition Skills in Persons With Aphasia

PURPOSE

The purpose of this study was to evaluate the ability of persons with aphasia, with and without hearing loss, to complete a commonly used open-set word recognition test that requires a verbal response. Furthermore, phonotactic probabilities and neighborhood densities of word recognition errors were assessed to explore potential underlying linguistic complexities that might differentially influence performance among groups.

METHOD

Four groups of adult participants were tested: participants with no brain injury with normal hearing, participants with no brain injury with hearing loss, participants with brain injury with aphasia and normal hearing, and participants with brain injury with aphasia and hearing loss. The Northwestern University Auditory Test No. 6 (NU-6; Tillman & Carhart, 1966) was administered. Those participants who were unable to respond orally (repeating words as heard) were assessed with the Picture Identification Task (Wilson & Antablin, 1980), permitting a picture-pointing response instead. Error patterns from the NU-6 were assessed to determine whether phonotactic probability influenced performance.

RESULTS

All participants with no brain injury and 72.7% of the participants with aphasia (24 out of 33) completed the NU-6. Furthermore, all participants who were unable to complete the NU-6 were able to complete the Picture Identification Task. There were significant group differences on NU-6 performance. The 2 groups with normal hearing had significantly higher scores than the 2 groups with hearing loss, but the 2 groups with normal hearing and the 2 groups with hearing loss did not differ from one another, implying that their performance was largely determined by hearing loss rather than by brain injury or aphasia. The neighborhood density, but not phonotactic probabilities, of the participants' errors differed across groups with and without aphasia.

CONCLUSIONS

Because the vast majority of the participants with aphasia examined could be tested readily using an instrument such as the NU-6, clinicians should not be reticent to use this test if patients are able to repeat single words, but routine use of alternative tests is encouraged for populations of people with brain injuries.

Feasibility of a low-cost hearing screening in rural Indiana

Background

Hearing loss remains a neglected public health issue in the rural and agricultural communities in the United States and therefore, promotion of a low-cost hearing screening may be important for these underserved populations. The major objectives of our study were to assess feasibility of a low-cost telephone-administered hearing test in rural Indiana and to identify the challenges, barriers and viable implementation strategies associated with this test. Also, we evaluated whether a focus group session could change the hearing health attitude of rural residents.

Methods

We recruited 126 adults from six rural Indiana counties who participated in study activities in the following order: 1) a pre-focus group demographic, knowledge and attitude survey, 2) a focus group for discussing the feasibility of a telephone-administered hearing screening, 3) a post focus group attitude survey and 4) hearing was screened using an audiometer and self-assessment scale. These activities generated both qualitative and quantitative data, which were subsequently analyzed.

Results

Hearing impairment was perceived as an important public health issue. Many participants expressed interests to try the low-cost National Hearing Test (NHT). However, participants recommended NHT to be facilitated by community organizations to provide access to landline phones. The focus group turned out to be an excellent awareness building activity producing significant improvement in hearing health attitudes. Comparison of self and audiometric evaluations indicated underestimation of hearing handicap in our rural study population.

Conclusions

The study results underscore the urgent need for an effective strategy to promote low-cost hearing screening in rural US communities.

An Exploration of the Associations Among Hearing Loss, Physical Health, and Visual Memory in Adults From West Central Alabama

PURPOSE

The purpose of this preliminary study was to explore the associations among hearing loss, physical health, and visual memory in adults living in rural areas, urban clusters, and an urban city in west Central Alabama.

METHOD

Two hundred ninety-seven adults (182 women, 115 men) from rural areas, urban clusters, and an urban city of west Central Alabama completed a hearing assessment, a physical health questionnaire, a hearing handicap measure, and a visual memory test.

RESULTS

A greater number of adults with hearing loss lived in rural areas and urban clusters than in an urban area. In addition, poorer physical health was significantly associated with hearing loss. A greater number of individuals with poor physical health who lived in rural towns and urban clusters had hearing loss compared with the adults with other physical health issues who lived in an urban city. Poorer hearing sensitivity resulted in poorer outcomes on the Emotional and Social subscales of the Hearing Handicap Inventory for Adults. And last, visual memory, a working-memory task, was not associated with hearing loss but was associated with educational level.

CONCLUSIONS

The outcomes suggest that hearing loss is associated with poor physical and emotional health but not with visual-memory skills. A greater number of adults living in rural areas experienced hearing loss compared with adults living in an urban city, and consequently, further research will be necessary to confirm this relationship and to explore the reasons behind it. Also, further exploration of the relationship between cognition and hearing loss in adults living in rural and urban areas will be needed.

Prevalência de perda auditiva em adolescentes e adultos jovens decorrentes de exposição a ruído social: meta-análise

RESUMO: A exposição a ruídos no lazer de adolescentes e jovens adultos tem chamado atenção, dada a repercussão da perda auditiva nessa população. Esse estudo propôs estimar a prevalência de perda auditiva dessa população decorrentes de exposição a ruídos sociais. Foram identificados 17 artigos para análise que atenderam aos critérios de seleção, sobre os quais se observaram informações de: delineamento, faixa etária, localização, modo de avaliação e a prevalência de perda auditiva. Nos estudos autorreferidos, a prevalência foi inferior a 2%, enquanto aqueles que realizam audiometria foi de 11,5 e de 15,8%. Concluiu-se uma heterogeneidade entre a prevalência de perda auditiva autorreferida e a mensurada por exames audiométricos na população pesquisada.

Review of interventions to increase hearing protective device use in youth who live or work on farms

AIMS AND OBJECTIVES

To identify and compare hearing protection interventions for youth working and living on farms.

BACKGROUND

Noise-induced hearing loss represents a significant risk factor for injury, disability and death in agricultural populations due to an inability to receive sensory information that can indicate dangerous situations. Despite the availability of hearing protection devices, rates of utilisation remain low, while rates of noise-induced hearing loss are high within the agricultural youth population.

DESIGN

Comprehensive review of the literature.

METHOD

Electronic database searches were conducted to identify research studies of hearing protection interventions for youth living or working on farms.

RESULTS

Three intervention studies were identified as meeting the review criteria, with additional reanalysis studies based on the original intervention studies. The intervention studies demonstrated increased use of hearing protection devices among youth who received the interventions compared to the control groups although audiometry testing results were not improved as a result of the intervention.

CONCLUSIONS

The findings of this review highlight the need for additional research into the effectiveness of hearing protection device use as a noise-induced hearing loss preventative measure in youth who live or work on farms and the creation of effective interventions to increase hearing protection device use and decrease Noise-induced hearing loss risk.

RELEVANCE TO CLINICAL PRACTICE

It is recommended that nurses be educated in the areas of health promotion relevant to farming communities to be able to effectively meet their rural clients' needs in relation to noise-induced hearing loss. Working with youth, families, and schools, as well as developing community partnerships, can facilitate the dissemination of hearing protection promotion.

Effects of common agricultural tasks on measures of hearing loss

BACKGROUND

Among agricultural populations, hearing loss caused by excessive noise exposure is common. However, examinations of associations between exposure to agricultural tasks and hearing loss are limited.

METHODS

Audiometry and lifetime exposure to 11 agricultural tasks were analyzed among 1,568 participants. Gender stratified multivariable linear regression was used to estimate associations between exposure duration and three hearing loss metrics.

RESULTS

Among men, significant associations were observed between hearing loss and hunting or target shooting, all-terrain vehicle (ATV) or motorcycle riding, chain saw use, electric or pneumatic tool use, living on a farm, and all agricultural tasks combined. When all significant exposure metrics were included in a single model, associations remained for hunting or target shooting, electric or pneumatic tool use and living on a farm. Significant associations were sparse among women, and in all cases paradoxical.

CONCLUSIONS

Despite imprecise estimation of noise exposure, specific agricultural tasks were associated with hearing loss.

Noise exposures of rural adolescents

PURPOSE

This project was conducted to characterize the noise exposure of adolescents living in rural and agricultural environments.

METHODS

From May to October, 25 adolescents ages 13 through 17, living either on a farm or a rural nonfarm, were enrolled in the study. Subjects received training on the correct operation and use of personal noise dosimeters and the proper way to record their daily tasks on activity cards. Subjects completed 4 days of self-monitoring noise dosimetry, 2 days in the first round (May-July) and 2 days in the second round (August-October). In addition to dosimetry, subjects completed activity logs of their daily tasks.

RESULTS

The mean daily noise exposures of adolescents living on farms and in nonfarm rural homes were between 55.4 dBA (A-weighted decibels) and 103.5 dBA, with 44% of the daily measurements greater than the National Institute of Occupational Safety and Health Recommended Exposure Level of 85 dBA. Task-based analysis of noise exposures found that activities involving mechanized equipment resulted in the highest exposures, while activities in the home resulted in the lowest exposure. No particular demographic group had a statistically higher noise exposure; therefore, specific factors apart from activities and noise sources could not be identified as risk factors for exposure to hazardous noise levels.

CONCLUSIONS

The results of this project indicate that rural adolescents complete a variety of activities and are exposed to noise sources with a broad range of decibel levels. While the exposures may change from day to day, there are occasions when exposure to noise exceeds the recommended levels.

Highly variable population-based prevalence rates of unilateral hearing loss after the application of common case definitions

OBJECTIVES

This study shows how population-based estimates of the prevalence of unilateral hearing loss (UHL) in children aged 6 to 19 yrs can differ considerably with various applications of commonly accepted case definitions. It also examines demographic variables and risk factors related to UHL.

DESIGN

The Third National Health and Nutrition Examination Survey, conducted from 1988 to 1994, is a national population-based, cross-sectional survey. This study examined results of audiometric testing at 0.5 to 8 kHz and demographic data from in-person examination interviews. Three definitions of UHL were used: (1) 0.5, 1, and 2 kHz > or = 15 dB pure-tone average (PTA); (2) 0.5, 1, 2, and 4 kHz > or = 15 dB PTA; and (3) 0.5, 1, and 2 kHz > or = 20 dB or PTA >25 dB at two or more frequencies above 2 kHz (3, 4, 6, and 8 kHz). Case definitions 2 and 3 are not merely subsets of case definition 1. Some overlap exists between the groups, but each case definition classifies a proportion of children who fall uniquely under that case definition. Inclusion of participants based on tympanometry results (test of middle ear function) was also examined as were demographic characteristics and risk factors associated with UHL.

RESULTS

Overall, the weighted proportion of children with UHL using case definition 1 was 6.3% (approximately 3,213,000 children nationally); using case definition 2, it was 5.8% (approximately 2,958,000 nationally); using case definition 3, it was 3.0% (approximately 1,530,000 nationally). For all three case definitions, children who failed tympanometry were at higher risk for UHL than children who passed. For case definition 2, children from rural areas were at higher risk for UHL than were children from urban areas.

CONCLUSIONS

This study demonstrates that different applications of well-accepted case definitions of UHL can influence population-based prevalence estimates, in this study by as much as a factor of 2. These findings highlight the importance of controlling for tympanometry status as a risk factor in such estimates. Which demographic characteristics and risk factors are significantly associated with hearing loss seem to vary depending on the case definition. These findings have implications for the interpretation of prevalence rates and risk factors in the literature on hearing loss in general. Prevalence rate estimates require careful consideration of the case definition of hearing loss, tympanometry status, and demographic characteristics.

A recessive Mendelian model to predict carrier probabilities of DFNB1 for nonsyndromic deafness

Mutations in the DFNB1 locus, where two connexin genes are located (GJB2 and GJB6), account for half of congenital cases of nonsyndromic autosomal recessive deafness. Because of the high frequency of DFNB1 gene mutations and the availability of genetic diagnostic tests involving these genes, they are the best candidates to develop a risk prediction model of being hearing impaired. People undergoing genetic counseling are normally interested in knowing the probability of having a hearing impaired child given his/her family history. To address this, a Mendelian model that predicts the probability of being a carrier of DFNB1 mutations, using family history of deafness, has been developed. This probability will be useful as additional information to decide whether or not a genetic test should be performed. This model incorporates Mendelian mode of inheritance, the age of onset of the disease, and the current age of hearing family members. The carrier probabilities are obtained using Bayes' theorem, in which mutation prevalence is used as the prior distribution. We have validated our model by using information from 305 families affected with congenital or progressive nonsyndromic deafness, in which genetic analysis of GJB2 and GJB6 had already been performed. This model works well, especially in homozygous carriers, showing a high discriminative power. This indicates that our proposed model can be useful in the context of clinical counseling of autosomal recessive disorders.

A Comparison of Self-Reported Hearing and Pure Tone Threshold Average in the Iowa Farm Family Health and Hazard Survey

BACKGROUND

Self-reported hearing measures are useful for surveying hearing loss in a population because they are short, and easy to administer by either questionnaire or telephone. This study aims to assess the performance of several self-reported hearing measures to identify hearing loss in a group of Iowa farmers.

METHODS

The study subjects were 98 male farmers who participated in the Iowa Farm Family Health and Hazard Survey. We tested three self-reported hearing measures; the hearing screening questions, the Rating Scale for Each Ear (RSEE), and the Health, Education and Welfare-Expanded Hearing Ability Scale (HEW-EHAS), which were originally developed and implemented in the National Health Interview Survey. The sensitivity and specificity of the self-reported hearing measures were assessed by comparing them with pure tone threshold averages. These sensitivity and specificity measures were compared between younger and older age groups.

RESULTS

The sensitivities of the screening questions, RSEE, and HEW-EHAS were 73.0%, 66.7%, and 53.3%, respectively. The specificities of the self-reported hearing measures were similar, which ranged from 81.4% to 84.8%. The sensitivities of the self-reported hearing measures were higher in the younger age group while the specificities were higher in the older age group.

CONCLUSIONS

The results of this study support the use of simple screening questions in identifying hearing loss among farmers.