Service delivery approaches related to hearing aids in low- and middle-income countries or resource-limited settings: A systematic scoping review.

Hearing loss is an important global public health issue which can be alleviated through treatment with hearing aids. However, most people who would benefit from hearing aids do not receive them, in part due to challenges in accessing hearing aids and related services, which are most salient in low- and middle-income countries (LMIC) and other resource-limited settings. Innovative approaches for hearing aid service delivery can overcome many of the challenges related to access, including that of limited human resources trained to provide ear and hearing care. The purpose of this systematic scoping review is to synthesize evidence on service delivery approaches for hearing aid provision in LMIC and resource-limited settings. We searched 3 databases (PubMed, Scopus, Ovid MEDLINE) for peer-reviewed articles from 2000 to 2022 that focused on service delivery approaches related to hearing aids in LMIC or resource-limited settings. Fifteen peer-reviewed articles were included, which described hospital-based (3 studies), large-scale donation program (1 studies), community-based (7 studies), and remote (telehealth; 4 studies) service delivery approaches. Key findings are that hearing aid services can be successfully delivered in hospital- and community-based settings, and remotely, and that both qualified hearing care providers and trained non-specialists can provide quality hearing aid services. Service delivery approaches focused on community-based and remote care, and task sharing among qualified hearing care providers and trained non-specialists can likely improve access to hearing aids worldwide, thereby reducing the burden of untreated hearing loss.

Establishing multifactorial risk factors for adult-onset hearing loss: A systematic review with topic modelling and synthesis of epidemiological evidence.

BACKGROUND: This systematic review explores the multifaceted nature of risk factors contributing to adult-onset HL. The objective was to synthesise the most recent epidemiological evidence to generate pooled proportional incidences for the identified risk factors. METHODS: We conducted an extensive search of electronic databases (MEDLINE, EMBASE, and psychINFO) for studies providing epidemiological evidence of risk factors associated with hearing loss. Topic modelling using Latent Dirichlet Allocation (LDA) was first conducted to determine how many risk factor themes were available from the papers. Data were analysed by calculating the pooled proportional incidence using a meta-analysis of proportions. RESULTS: From the 72 studies reviewed, six key risk factor themes emerged through LDA topic modelling. The review identified ototoxicity, primarily caused by cancer treatments and antibiotics, infectious diseases like COVID-19, occupational noise exposure, lifestyle factors, health conditions, biological responses, and age progression as significant risk factors for HL. The highest proportional incidence was found with cancer-related ototoxicity at 55.4% (95%CI: 39.0-70.7), followed closely by ototoxicity from infectious diseases at 50.0% (95%CI: 28.5-71.5). This high proportional incidence suggests the need to explore less destructive therapies and proactively monitor hearing function during treatments. CONCLUSIONS: The findings of this review, combined with the synthesis of epidemiological evidence, enhance our understanding of hearing loss (HL) pathogenesis and highlight potential areas for intervention, thereby paving the way for more effective prevention and management of adult-onset hearing loss in our ageing global population.

High Levels of Satisfaction Among Hearing Aid Users in a Pilot Study for Sustainable Low-Cost Auditory Rehabilitation Services in Samoa.

The provision of locally sustainable hearing aid device services is desirable in the Pacific Islands. The aim of the present study was (1) To assess the suitability of low-cost pre-programmable hearing aids in Samoa, a Polynesian nation of the Pacific Islands, and (2) To develop translations of established auditory rehabilitation questionnaires into the FaaSamoan language for clinical, public health, and research applications. A cross-over trial of 2 low-cost pre-programmable hearing aids among 20 adults in Samoa was conducted as part of a larger UN-funded global audiology study. The International Outcome Inventory for Hearing Aids, the International Outcome Inventory for Hearing Aids for Significant Others, and the Revised Hearing Handicap Inventory questionnaires were translated into the FaaSamoan language to assess the self-reported outcomes of study participants. Overall, high scores were measured for the self-reported outcome measures, suggesting good levels of use and satisfaction with the hearing aid devices. Overall, results found that once a hearing aid was fitted that 67.6% of participants reported no hearing handicap, 32.4% reported a mild to moderate hearing handicap, and no participant reported a significant hearing handicap.

Early Life Influences on Hearing in Adulthood: a Systematic Review and Two-Step Individual Patient Data Meta-Analysis.

OBJECTIVES: Adverse prenatal and early childhood development may increase susceptibility of hearing loss in adulthood. The objective was to assess whether indices of early development are associated with adult-onset hearing loss in adults ≥18 years. DESIGN: In a systematic review and meta-analysis, four electronic databases were searched for studies reporting associations between indices of early development (birth weight and adult height) and adult-onset hearing loss in adults ≥18 years. We screened studies, extracted data, and assessed risk of bias. Authors were contacted to provide adjusted odds ratios from a logistic regression model for relationships between birth weight/adult height and normal/impaired hearing enabling a two-step individual patient data random-effects meta-analysis to be carried out. The study is registered with PROSPERO, CRD42020152214. RESULTS: Four studies of birth weight and seven of adult height were identified. Three studies reported smaller birth weight associated with poorer adult hearing. Six studies reported shorter height associated with poorer hearing. Risk of bias was low to moderate. Four studies provided data for two-step individual patient data random-effects meta-analysis. Odds of hearing impairment were 13.5% lower for every 1 kg increase in birth weight [OR: 0.865 (95% confidence interval: 0.824 to 0.909)] in adulthood over two studies (N=81,289). Every 1 cm increase in height was associated with a 3% reduction in the odds of hearing impairment [OR: 0.970 (95% confidence interval: 0.968 to 0.971)] over four studies (N=156,740). CONCLUSIONS: Emerging evidence suggests that adverse early development increases the likelihood of hearing impairment in adulthood. Research and public health attention should focus on the potential for prevention of hearing impairment by optimizing development in early life.

Size at birth and cognitive function among rural adolescents: a life course epidemiology study protocol of the Kisalaya cohort in Mysuru, South India.

INTRODUCTION: It is proven that adverse intrauterine environment results in 'early life programming,' alterations in metabolism and physiological development of the fetus, often termed as 'Developmental Origins of Health and Disease' (DOHaD) resulting in a smaller size at birth, greater non-communicable diseases (NCD) risk factors during childhood and adolescence, and cardiometabolic disorders in adulthood. Nevertheless, very few studies have examined the relationship between DOHaD programming and cognition. This study aims to examine if impaired prenatal growth indicated by birth weight is associated with cognition among adolescents in the Kisalaya cohort, a rural birth cohort in South India, thus providing newer insights into DOHaD programming for adolescent mental health in a low-income and middle-income country setting. METHODS AND ANALYSIS: Kisalaya cohort was established in 2008, to provide integrated antenatal care and HIV testing using mobile clinics to improve maternal and child health outcomes. This cohort included pregnant women residing in 144 villages of Mysuru Taluk (rural) who received antenatal care through mobile clinics and delivered their children between 2008 and 2011. Data related to mother-infant dyads for all pregnant women who received care in the Kisalaya programme are available for this study. Presently, children born to women who received care through Kisalaya are adolescents between 10 and 12 years. At this point, information would be collected on sociodemographic data and assessments of mental health, stressful life events, cognition, vision, speech, language, hearing and anthropometric measures would be done and relevant maternal data and child data, available from the cohort would be retracted for analysis. We plan to retrace as many adolescents as possible out of 1544 adolescents who are currently available for study excluding twins, abortions, stillbirths and postdelivery deaths. Analyses will be extended to construct a life course pathway for cognition using structural equation modelling.

Natural history of tinnitus in adults: a cross-sectional and longitudinal analysis.

OBJECTIVE: To assess incidence and changes in tinnitus and bothersome tinnitus as well as associated risk factors in a large sample of UK adults. DESIGN: Prospective cohort study. SETTING: UK. PARTICIPANTS: For cross-sectional analysis, a group of 168 348 participants aged between 40 and 69 years with hearing and tinnitus data from the UK Biobank resource. Longitudinal analysis included a subset of 4746 people who attended a 4-year retest assessment. MAIN OUTCOME MEASURES: Presence and bothersomeness of tinnitus. RESULTS: 17.7% and 5.8% of participants reported tinnitus or bothersome tinnitus, respectively. The 4-year incidence of tinnitus was 8.7%. Multivariate logistic regression models suggested that age, hearing difficulties, work noise exposure, ototoxic medication and neuroticism were all positively associated with both tinnitus and bothersome tinnitus. Reduced odds of tinnitus, but not bothersome tinnitus, was seen in alcohol drinkers versus non-drinkers. Male gender was associated with increased odds of tinnitus, while female gender was associated with increased odds of bothersome tinnitus. At follow-up, of those originally reporting tinnitus, 18.3% reported no tinnitus. Of those still reporting tinnitus, 9% reported improvement and 9% reported tinnitus becoming more bothersome, with the rest unchanged. Male gender and alcohol consumption were associated with tinnitus being reported less bothersome, and hearing difficulties were associated with the odds of tinnitus being reported as more bothersome. CONCLUSIONS: This study is one of the few to provide data on the natural history of tinnitus in a non-clinical population, suggesting that resolution is relatively uncommon, with improvement and worsening of symptoms equally likely. There was limited evidence for any modifiable lifestyle factors being associated with changes in tinnitus symptoms. In view of the largely persistent nature of tinnitus, public health strategies should focus on: (1) primary prevention and (2) managing symptoms in people that have tinnitus and monitoring changes in bothersomeness.

A National Survey of Hearing Loss in the Philippines.

This study aimed to estimate the prevalence of hearing loss in the Philippines using a nationally representative sample. A cross-sectional national survey was undertaken utilizing a 3-stage stratified cluster design. Participants in the present study comprised 2275 adults and children with pure tone hearing assessment results. Prevalence of moderate or worse hearing loss, defined as 4FA ≥41 dBHL, was 7.5% in children <18 years, 14.7% in adults between 18 and 65 years, and 49.1% in adults >65 years. Factors associated with greater risk of moderate hearing loss in the better ear were presence of a middle ear condition (adjusted odds ratio = 2.39, 95% confidence interval = 1.49-3.85) and socioeconomic status (household income; adjusted odds ratio = 1.64, 95% confidence interval = 1.23-2.19). Age was also associated with increased risk, with adjusted odds ratios varying with age category. Prevalence of wax occlusion and outer and middle ear disease was 12.2% and 14.2%, respectively. Prevalence of hearing loss, outer, and middle ear disease appear comparatively high in the Philippines when compared with rates reported in high-income countries. Higher proportions of severe to profound hearing loss were also identified, indicating that there is both an increased prevalence and severity of hearing loss in this population.

Hearing aid or "band aid"? Evaluating large scale hearing aid donation programmes in the Philippines.

Objective: This study aimed to evaluate the effectiveness of two large scale hearing aid donation programmes in the Philippines.Design: Real ear measurements were made on all hearing aids, for comparison to NAL-RP prescription targets. Performance measures and the International Outcomes Inventory for Hearing Aids (IOI-HA) data was collected from a subsample of participants.Study sample: A total of 101 and 153 low socioeconomic status participants were sampled just after, or 6 months after receiving their hearing devices in each of the programmes evaluated, respectively.Results: Of the 189 hearing aids sampled at fitting, and the 195 hearing aids sampled at 6 months post fitting, less than 2% were within ±5dB of prescription target. At 6 months post fitting IOI-HA outcomes were essentially comparable to those described in the literature but were not a good predictor of fit to prescriptive target.Conclusions: Objective measures of hearing aid outcome were poor and showed no relationship to subjective outcome measures. Although able to fit large numbers in short time frames, to avoid a band aid solution, changes to such programmes should be made including: a focus on those with aidable hearing losses, increased opportunity for follow up care, and improved device quality.