Language and health-related quality of life outcomes of children early-detected with unilateral and mild bilateral hearing loss.

Introduction: We aimed to describe the language and health-related quality of life (HRQoL) outcomes of children early-identified with unilateral or mild bilateral permanent hearing loss. This was a cross-sectional community-based study of children with mild bilateral or unilateral permanent hearing loss (including unilateral auditory neuropathy spectrum disorder (ANSD)), drawn from a population-based databank in Victoria, Australia. Methods: Enrolment in this databank is independent of early intervention and amplification approaches. Language and caregiver-reported HRQoL outcomes are described by type and degree of loss at three timepoints across child development: at age 2 years (n = 255), 5-7 years (n = 173) and 9-12 years (n = 45). Results: Across all age groups, average language outcomes were poorer than population normative scores by between a half to two thirds of a standard deviation. Children with mild bilateral hearing loss demonstrated poorer average language outcomes than children with unilateral hearing loss, particularly at younger ages. Children with unilateral ANSD showed language outcomes comparable to their peers with unilateral profound hearing loss. Children had poorer HRQoL psychosocial scores compared to physical scores, without obvious patterns of outcomes linked to degree or type of hearing loss. Discussion: This study demonstrates children with early-identified unilateral or mild bilateral hearing loss have average language and HRQoL outcomes poorer than population normative expectations from an early age. These outcomes are observed at later ages across childhood. These findings provide a contemporary description of language and quality of life outcomes for children identified but not targeted by universal newborn hearing screening and raise questions of how to provide better support for these populations of children and their families.

Mild matters: trial learnings and importance of community engagement in research for early identified bilateral mild hearing loss.

Introduction: Early identification of mild hearing loss has resulted in early hearing amplification without adequate evidence of effectiveness. This paper describes learnings from a pilot trial, combined with a qualitative study, to highlight the importance of community engagement in designing research studies to determine whether early amplification benefits young children with bilateral mild hearing loss. Methods: PART 1 of the study is a proof-of-concept non-blinded multi-centre randomised controlled trial (RCT) of hearing device fitting vs. no fitting aimed to gather preliminary data and determine its acceptability/feasibility in children <2 years old with bilateral mild hearing loss. Results: PART 2 is a qualitative study to understand the barriers/enablers to RCT participation. Of 40 potentially eligible families, nine (23%) declined, three were uncontactable (7%), 26 (65%) ineligible: of these, nine (35%) did not meet hearing threshold inclusion criteria, 11 (42%) were already fitted or had made decisions on fitting hearing device, two (7%) had conductive loss and four (16%) were ineligible for other reasons. Two of 11 (18%) eligible families were randomised. With the limited sample size, outcome measures were not compared between groups. Both participants completed the trial, reported the RCT to be acceptable, and neither changed group post-enrolment. Discussion: Whilst recruitment uptake could potentially be increased by altering the eligibility criteria, better communication with and reimbursement of clinicians as recruiters, and improving awareness of the study amongst external stakeholders, the RCT methodology does not conform to family-centred practice, and potentially raises ethical concerns regarding potential adverse consequences of not offering early amplification. Parental perception of losing control over choice of management due to randomisation is not an easily modifiable factor. Alternative methodological approaches without randomisation are required to determine whether hearing amplification benefits infants with mild hearing loss.Clinical Trial Registration: identifier [ACTRN12618001608257].

Spoken Expressive Vocabulary in 2-Year-Old Children with Hearing Loss: A Community Study.

Through a cross-sectional community study of 2044 children aged 2 years, we (1) examine the impact of hearing loss on early spoken expressive vocabulary outcomes and (2) investigate how early intervention-related factors impact expressive vocabulary outcomes in children with hearing loss predominantly identified through universal newborn hearing screening. We used validated parent/caregiver-reported checklists from two longitudinal cohorts (302 children with unilateral or bilateral hearing loss, 1742 children without hearing loss) representing the same population in Victoria, Australia. The impact of hearing loss and amplification-related factors on vocabulary was estimated using g-computation and multivariable linear regression. Children with versus without hearing loss had poorer expressive vocabulary scores, with mean scores for bilateral loss 0.5 (mild loss) to 0.9 (profound loss) standard deviations lower and for unilateral loss marginally (0.1 to 0.3 standard deviations) lower. For children with hearing loss, early intervention and amplification by 3 months, rather than by 6 months or older, resulted in higher expressive vocabulary scores. Children with hearing loss demonstrated delayed spoken expressive vocabulary despite whole-state systems of early detection and intervention. Our findings align with calls to achieve a 1-2-3 month timeline for early hearing detection and intervention benchmarks for screening, identification, and intervention.

Auditory neuropathy in mice and humans with Friedreich ataxia.

OBJECTIVE: Recent studies have found that human Friedreich ataxia patients have dysfunction of transmission in the auditory neural pathways. Here, we characterize hearing deficits in a mouse model of Friedreich ataxia and compare these to a clinical population. METHODS: Sixteen mice with a C57BL/6 background were evaluated. Eight were YG8Pook/J animals (Friedreich ataxia phenotype) and eight wild-type mice served as controls. Auditory function was assessed between ages 6 and 12 months using otoacoustic emissions and auditory steady-state responses. At study end, motor deficit was assessed using Rotorod testing and inner ear tissue was examined. Thirty-seven individuals with Friedreich ataxia underwent auditory steady-state evoked potential assessment and response amplitudes were compared with functional hearing ability (speech perception-in-noise) and disease status was measured by the Friedreich Ataxia Rating Scale. RESULTS: The YG8Pook/J mice showed anatomic and functional abnormality. While otoacoustic emission responses from the cochlear hair cells were mildly affected, auditory steady-state responses showed exaggerated amplitude reductions as the animals aged with Friedreich ataxia mice showing a 50-60% decrease compared to controls who showed only a 20-25% reduction (F(2,94) = 17.90, p < 0.00). Furthermore, the YG8Pook/J mice had fewer surviving spiral ganglion neurons, indicating greater degeneration of the auditory nerve. Neuronal density was 20-25% lower depending on cochlear region (F(1, 30) = 45.02, p < 0.001). In human participants, auditory steady-state response amplitudes were correlated with both Consonant-Nucleus-Consonant word scores and Friedreich Ataxia Rating Scale score. INTERPRETATION: This study found degenerative changes in auditory structure and function in YG8Pook/J mice, indicating that auditory measures in these animals may provide a model for testing Friedreich ataxia treatments. In addition, auditory steady-state response findings in a clinical population suggested that these scalp-recorded potentials may serve as an objective biomarker for disease progress in affected individuals.

Etiology, Comorbidities, and Health Service Use in a Clinical Cohort of Children With Hearing Loss.

OBJECTIVE: To examine etiology, comorbidities, and health service use in a cohort of children with permanent hearing loss. Receiving an etiological diagnosis can inform reproductive planning, rehabilitation outcomes, predict additional disabilities, and direct intervention or management decisions. DESIGN: Retrospective audit of 518 deaf/hard-of-hearing children attending a tertiary pediatric outpatient clinic (2016-2019) using descriptive statistics. We used linear regression to investigate the relationship between degree of hearing loss, comorbidities, and health service use. RESULTS: Of the 518 children who attended the clinic, 481 (92.9%) proceeded with testing for etiology. Most children (399/518, 77.0%) were diagnosed with hearing loss by 3 mo of age. Of the children tested, the cause of hearing loss was confirmed in 234/481 (48.6%), suspected in 113/481 (23.5%), and unknown in 134/481 (27.9%); 17/341 (5.0%) had congenital cytomegalovirus (CMV), 17/320 (5.3%) had enlarged vestibular aqueducts, 67/213 (31.5%) of children with bilateral hearing loss had connexin mutation, and 25/72 (34.7%) of children with unilateral loss had hypoplastic/absent cochlear nerve on imaging. The odds of having a definitive/suspected diagnosis were twice as likely for indivduals with profound hearing loss than mild hearing loss (OR 2.1; 95% CI, 1.2-3.9; P = 0.02). The majority (348/518, 67.2%) of children had medical comorbidities, and most children attended otolaryngology (453/518, 87.5%), early intervention (358/518, 69.1%), and genetic (287/518, 55.4%) services. CONCLUSIONS: Children with hearing loss have diverse etiologies, most have comorbidities, and attend multiple services. Most families elected to proceed with diagnostic testing for etiology. Current guidelines and expanded access to genetic testing identified a confirmed/suspected etiological diagnosis in 72.1% of children tested. The number of comorbidities correlated with service use, regardless of hearing loss severity.

Predictors of Early Language Outcomes in Children with Connexin 26 Hearing Loss across Three Countries.

GJB2-associated hearing loss (GJB2-HL) is the most common genetic cause of hearing loss in children. However, little is known about the clinical characteristics and early language outcomes in population-oriented samples including children with different degrees of hearing loss. Insight into these characteristics are relevant for the counselling of parents. Our sample consisted of 66 children at approximately 2 years of age (17-32 months) with bilateral hearing loss due to GJB2 from three population-based cohorts in Austria, Australia and the Netherlands. Predictors of early vocabulary, including demographic, audiological, genetic and intervention variables and the role of medical comorbidities and nonverbal cognition were examined. The vocabulary scores of children with GJB2-HL were approximately 0.7 standard deviations (SDs) below the norms of children with typical hearing. Age at access to family-centered early intervention and first-born position among siblings predicted language outcomes, whereas the degree of hearing loss and genetic subtype were not significantly correlated with expressive vocabulary. In children with GJB2-HL, early access to family-centered early intervention significantly affected language outcomes at the age of two.

Mild matters: parental insights into the conundrums of managing mild congenital hearing loss.

OBJECTIVE: To explore and describe parental experiences related to the management of mild bilateral congenital hearing loss in children. DESIGN: Using qualitative methods, we conducted semi-structured interviews with parents/caregivers until saturation of themes was achieved. We analysed transcripts using inductive content analysis. STUDY SAMPLE: Caregivers of children under 3-years-old with mild bilateral sensorineural hearing loss. RESULTS: We interviewed 12 parents. Parental perception of advice regarding hearing aid fitting was varied; almost all children were offered hearing aids. Perceived positives related to hearing aids: feeling empowered that action has been taken; improvements in the child's hearing perception and; facilitation of behavioural management. Perceived negatives of hearing aid use: difficulties with compliance resulting in parental frustration and guilt, damage/loss of equipment, discomfort, parental discord, altered quality of natural sound and potential bullying/stigma. Some parents were ambivalent about the effect of the hearing aids. Where hearing aids were offered and not fitted, there was significant ongoing uncertainty, and the family carried the burden of their decision. CONCLUSIONS: There was a wide variation in perceived advice regarding early hearing aid fitting in children with mild bilateral hearing loss. We identified parental perceptions of positive/negative impacts of hearing aid fitting and potential perceived harms from not fitting.

Ear Infection Trajectories and Academic, Behavioral, and Quality-of-Life Outcomes: A Population-Based Longitudinal Study.

OBJECTIVE: The purpose of this study was to investigate (1) typical trajectories of parent-reported ear infections throughout childhood and (2) their associations with child outcomes. METHOD: Design and participants: Two parallel cohorts assessed biennially from 2004 to 2014 spanning ages 0-1 to 10-11 years (B cohort, n = 3721) and ages 4-5 to 14-15 years (K cohort, n = 3489) in the Longitudinal Study of Australian Children. Ear infection: Parent-reported ongoing ear infections (B: waves 1-6; K: waves 1, 2, 4, and 5). Outcomes (wave 6): National academic standardized test, teacher-reported learning, parent- and teacher-reported behavior, and self-reported quality of life. Analysis: Latent class models identified ear infection trajectories. Linear regression quantified associations between trajectories and outcomes. RESULTS: Four probability trajectories of ear infections emerged in both cohorts: "consistently low" (B 86.2%, K 87.0%), "moderate to low" (5.5%, 9.7%), "low to moderate" (7.0%, 1.5%), and "consistently high" (1.4%, 1.8%). In K cohort, the "consistently high" group had the worst outcomes (effect sizes 0.2-0.8 SDs), with effect sizes largest for psychosocial and language outcomes. "Moderate to low" and "low to moderate" groups showed marginal to no academic associations, although behavior and quality-of-life scores were 0.2 to 0.3 SDs poorer than the "consistently low" group. Similar but attenuated associations were seen in B cohort. CONCLUSION: Sizable adverse adolescent outcomes follow parent reports of persistent ongoing ear infections throughout childhood. Despite a possibility of reverse causation, this suggests that cumulative rather than age-specific ear infections are most important to outcomes. Clinicians may generally be reassuring about ongoing ear infections limited to either early or middle childhood but should proactively identify and manage the small subgroup whose early infections persist throughout the elementary school years.

Predicting speech-sound disorder outcomes in school-age children with hearing loss: The VicCHILD experience.

BACKGROUND: Congenital hearing loss is the most common birth anomaly, typically influencing speech and language development, with potential for later academic, social and employment impacts. Yet, surprisingly, the nuances of how speech is affected have not been well examined with regards to the subtypes of speech-sound disorder (SSD). Nor have the predictors of speech outcome been investigated within a sizeable population cohort. AIMS: (1) To describe the subtypes and prevalence of SSD in children with hearing loss. (2) To determine which characteristics of hearing loss predict the presence of SSD. METHODS & PROCEDURES: A total of 90 children (5-12 years of age) with permanent hearing loss were recruited from an Australian population cohort. Children completed a standardized speech assessment to determine the presence and subtype of SSD. Logistic regression was used to determine the predictors of speech outcome. Demographic, developmental and hearing-related predictors were examined. OUTCOMES & RESULTS: The prevalence of speech disorder overall was 58%, with the most common subtype being phonological delay in 49% of the sample. Factors most predictive of speech disorder were being male, younger and a bimodal user (i.e., using both a hearing aid and a cochlear implant). CONCLUSIONS & IMPLICATIONS: This is the first study, in a sizeable cohort, to describe the prevalence and predictive factors for SSD associated with hearing loss. Clinically, it could be beneficial to implement earlier targeted phonological interventions for children with hearing loss. What this paper adds What is already known on this subject Speech issues are common in children with hearing loss; however, the breakdown of subtypes of SSD (e.g., articulation versus phonological disorder) have not been previously described in a population cohort. This distinction is relevant, as each subtype calls for specific targeted intervention. Studies examining factors predictive of speech outcomes, across a range of hearing levels, are also lacking in a population cohort. What this paper adds to existing knowledge Data suggest the most common type of SSD in children with hearing loss is phonological delay. Males, younger children, and bimodal users were at greater risk of having a subtype of SSD. What are the potential or actual clinical implications of this work? The results are clinically pertinent as the speech diagnosis determines the targeted treatment. Phonological delay is responsive to treatment, and early targeted intervention may improve prognosis for speech outcomes for children with hearing loss.

Academic, behavioural and quality of life outcomes of slight to mild hearing loss in late childhood: a population-based study.

OBJECTIVE: To investigate the associations of hearing thresholds and slight to mild hearing loss with academic, behavioural and quality of life outcomes in children at a population level. METHODS: Design and participants:children aged 11-12 years in the population-based cross-sectional Child Health CheckPoint study within the Longitudinal Study of Australian Children. Audiometry:mean hearing threshold across 1, 2 and 4 kHz (better and worse ear); slight/mild hearing loss (threshold of 16-40 decibels hearing loss (dB HL)). Outcomes: National Assessment Program - Literacy and Numeracy, language, teacher-reported learning, parent and teacher reported behaviour and self-reported quality of life. Analysis:linear regression quantified associations of hearing threshold/loss with outcomes. RESULTS: Of 1483 children (mean age 11.5 years), 9.2% and 13.1% had slight/mild bilateral and unilateral hearing loss, respectively. Per SD increment in better ear threshold (5.7 dB HL), scores were worse on several academic outcomes (eg, reading 0.11 SD, 95% CI 0.05 to 0.16), parent-reported behaviour (0.06 SD, 95% CI 0.01 to 0.11) and physical (0.09 SD, 95% CI 0.04 to 0.14) and psychosocial (0.06 SD, 95% CI 0.01 to 0.11) Pediatric Quality of Life Inventory (PedsQL). Compared with normally hearing children, children with bilateral slight/mild losses scored 0.2-0.3 SDs lower in sentence repetition, teacher-reported learning and physical PedsQL but not other outcomes. Similar but attenuated patterns were seen in unilateral slight/mild losses. CONCLUSIONS: Hearing thresholds and slight/mild hearing loss showed small but important associations with some child outcomes at 11-12 years. Justifying hearing screening or intervention at this age would require better understanding of its longitudinal and indirect effects, alongside effective management and appropriate early identification programmes.

Inflammation and hearing status in mid-childhood and mid-life: a population-based cross-sectional study.

BACKGROUND: Lifelong inflammation - known to be associated with many non-communicable diseases - has not been thoroughly investigated in hearing. We aimed to determine if glycoprotein A (GlycA), a novel biomarker of chronic inflammation, is associated with hearing acuity in mid-childhood and mid-life. METHODS: Population-based cross-sectional study within the Longitudinal Study of Australian Children with plasma GlycA and audiometry data (1169 children and 1316 parents). We calculated high Fletcher Index (mean threshold across 1, 2 and 4 kHz), defining hearing loss as threshold >15 decibel hearing level (dB HL) (better ear). Linear/logistic regression quantified associations of GlycA with hearing threshold/loss. RESULTS: Mean [standard deviation (SD)] high Fletcher Indices (dB HL) were 8.0 (5.7) for children and 13.1 (6.9) for adults, with 8.7% and 26.1% respectively showing hearing loss. 1-SD rise in GlycA (children 0.13 mmol/L, adults 0.17 mmol/L) predicted higher hearing thresholds for the lower individual frequencies [1 kHz: children ß 0.8, 95% confidence interval (CI) 0.3-1.3; adults ß 0.8, 95% CI 0.2-1.4]. This same pattern was evident for the high Fletcher Index (children ß 0.7, 95% CI 0.3-1.1; adults ß 0.8, 95% CI 0.3-1.4). This translated into 1-SD rise in GlycA predicting adult hearing loss [odds ratio (OR) 1.2, 95% CI 1.0-1.5] with similar but attenuated patterns in children. CONCLUSIONS: GlycA is associated with poorer hearing by mid-childhood. This potentially reframes hearing loss as a life-course condition with inflammatory antecedents common to other non-communicable diseases. Replication and mechanistic studies could inform causal inference and early prevention efforts.

Prevalence of Childhood Hearing Loss and Secular Trends: A Systematic Review and Meta-Analysis.

BACKGROUND: Better epidemiologic information on childhood hearing loss would inform research priorities and efforts to prevent its progression. OBJECTIVES: To estimate prevalence and secular trends in children's hearing loss. DATA SOURCES: We searched MEDLINE and Embase from January 1996 to August 2017. STUDY ELIGIBILITY CRITERIA: We included epidemiologic studies in English reporting hearing loss prevalence. STUDY APPRAISAL AND SYNTHESIS METHODS: The modified Leboeuf-Yde and Lauritsen tool was used to assess methodological quality. Meta-analyses combined study-specific estimates using random-effects models. PARTICIPANTS: Children 0 to 18 years of age. RESULTS: Among 88 eligible studies, 43.2% included audiometric measurement of speech frequencies. In meta-analyses, pooled prevalence estimates of slight or worse bilateral speech frequency losses >15 decibels hearing level (dB HL) were 13.1% (95% confidence interval [CI], 10.0-17.0). Using progressively more stringent cutpoints, pooled prevalence estimates were 8.1% (95% CI, 1.3-19.8) with >20 dB HL, 2.2% (95% CI, 1.4-3.0) with >25 dB HL, 1.8% (95% CI, 0.4-4.1) with >30 dB HL, and 0.9% (95% CI, 0.1-2.6) with >40 dB HL. Also, 8.9% (95% CI, 6.4-12.3) had likely sensorineural losses >15 dB HL in 1 or both ears, and 1.2% (95% CI, 0.5-2.1) had self-reported hearing loss. From 1990 to 2010, the prevalence of losses >15 dB HL in 1 or both ears rose substantially (all P for trend <.001). LIMITATIONS: The studies had high heterogeneity and offered limited information for hearing loss types and secular trend. CONCLUSIONS AND IMPLICATIONS: Childhood slight or worse hearing loss is prevalent and may be increasing. Advances in understanding hearing loss trajectories, causes, and prevention would require international repositories and longitudinal studies with audiometric data beginning in childhood. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO 2016 CRD42016034148.

How body composition influences hearing status by mid-childhood and mid-life: The Longitudinal Study of Australian Children.

BACKGROUND: Hearing loss is a disabling condition whose prevalence rises with age. Obesity-a risk factor common to many non-communicable diseases-now appears to be implicated. We aimed to determine: (1) cross-sectional associations of body composition measures with hearing in mid-childhood and mid-life and (2) its longitudinal associations with 10-year body mass index (BMI) trajectories. METHODS: Design & Participants: There were 1481 11-12-year-old children and 1266 mothers in the population-based cross-sectional CheckPoint study nested within the Longitudinal Study of Australian Children (LSAC). Anthropometry (CheckPoint): BMI, fat/fat-free mass indices, waist-to-height ratio; LSAC wave 2-6-biennial measured BMI. Audiometry (CheckPoint): Mean hearing threshold across 1, 2 and 4 kHz; hearing loss (threshold > 15 dB HL, better ear). ANALYSIS: Latent class models identifying BMI trajectories; linear/logistic regression quantifying associations of body composition/trajectories with hearing threshold/loss. RESULTS: Measures of adiposity, but not fat-free mass, were cross-sectionally associated with hearing. Fat mass index predicted the hearing threshold and loss in children (ß 0.6, 95% confidence interval (CI) 0.3-0.8, P < 0.001;, odds ratio (OR) 1.2, 95% CI 1.0-1.4, P = 0.05) and mothers (ß 0.8, 95% CI 0.5-1.2, P < 0.001; OR 1.2, 95% CI 1.1-1.4, P = 0.003). Concurrent obesity (OR 1.5, 95% CI 1.1-2.1, P = 0.02) and waist-to-height ratio (WHtR) ≥ 0.6 (OR 1.6, 95% CI 1.2-2.3, P = 0.01) predicted maternal hearing, with similar but attenuated patterns in children. In longitudinal analyses, mothers', but not children's, BMI trajectories predicted hearing (OR for severely obese 3.0, 95% CI 1.4-6.6, P = 0.01). CONCLUSIONS: Concurrent adiposity and decade-long BMI trajectories showed small, but clear, associations with poor hearing in mid-life women, with emergent patterns by mid-childhood. This suggests that obesity may play a role in the rising global burden of hearing loss. Replication and mechanistic and body compositional studies could elucidate possible causal relationships.

Deep phenotyping of speech and language skills in individuals with 16p11.2 deletion.

Recurrent deletions of a ~600-kb region of 16p11.2 have been associated with a highly penetrant form of childhood apraxia of speech (CAS). Yet prior findings have been based on a small, potentially biased sample using retrospectively collected data. We examine the prevalence of CAS in a larger cohort of individuals with 16p11.2 deletion using a prospectively designed assessment battery. The broader speech and language phenotype associated with carrying this deletion was also examined. 55 participants with 16p11.2 deletion (47 children, 8 adults) underwent deep phenotyping to test for the presence of CAS and other speech and language diagnoses. Standardized tests of oral motor functioning, speech production, language, and non-verbal IQ were conducted. The majority of children (77%) and half of adults (50%) met criteria for CAS. Other speech outcomes were observed including articulation or phonological errors (i.e., phonetic and cognitive-linguistic errors, respectively), dysarthria (i.e., neuromuscular speech disorder), minimal verbal output, and even typical speech in some. Receptive and expressive language impairment was present in 73% and 70% of children, respectively. Co-occurring neurodevelopmental conditions (e.g., autism) and non-verbal IQ did not correlate with the presence of CAS. Findings indicate that CAS is highly prevalent in children with 16p11.2 deletion with symptoms persisting into adulthood for many. Yet CAS occurs in the context of a broader speech and language profile and other neurobehavioral deficits. Further research will elucidate specific genetic and neural pathways leading to speech and language deficits in individuals with 16p11.2 deletions, resulting in more targeted speech therapies addressing etiological pathways.

Cross-sectional epidemiology of hearing loss in Australian children aged 11-12 years old and 25-year secular trends.

OBJECTIVE: In a national study of Australian children aged 11-12 years old, we examined the (1) prevalence and characteristics of hearing loss, (2) its demographic risk factors and (3) evidence for secular increases since 1990. METHODS: This is a cross-sectional CheckPoint wave within the Longitudinal Study of Australian Children. 1485 children (49.8% retention; 49.7% boys) underwent air-conduction audiometry. Aim 1: hearing loss (≥16 decibels hearing level (dB HL)) was defined in four ways to enable prior/future comparisons: high Fletcher Index (mean of 1, 2 and 4 kHz; primary outcome relevant to speech perception), four-frequency (1, 2, 4 and 8 kHz), lower frequency (1 and 2 kHz) and higher frequency (4 and 8 kHz); aim 2: logistic regression of hearing loss by age, gender and disadvantage index; and aim 3: P for trend examining CheckPoint and reported prevalence in studies arranged by date since 1990. RESULTS: For high Fletcher Index, the prevalence of bilateral and unilateral hearing loss ≥16 dB HL was 9.3% and 13.3%, respectively. Slight losses (16-25 dB HL) were more prevalent than mild or greater (≥26 dB HL) losses (bilateral 8.5% vs 0.8%; unilateral 12.5% vs 0.9%), and lower frequency more prevalent than higher frequency losses (bilateral 11.0% vs 6.9%; unilateral 15.4% vs 11.5%). Demographic characteristics did not convincingly predict hearing loss. Prevalence of bilateral/unilateral lower and higher frequency losses ≥16 dB HL has risen since 1990 (all P for trend <0.001). CONCLUSIONS AND RELEVANCE: Childhood hearing loss is prevalent and has risen since 1990. Future research should investigate the causes, course and impact of these changes.

The use of listening devices to ameliorate auditory deficit in children with autism.

OBJECTIVES: To evaluate both monaural and binaural processing skills in a group of children with autism spectrum disorder (ASD) and to determine the degree to which personal frequency modulation (radio transmission) (FM) listening systems could ameliorate their listening difficulties. STUDY DESIGN: Auditory temporal processing (amplitude modulation detection), spatial listening (integration of binaural difference cues), and functional hearing (speech perception in background noise) were evaluated in 20 children with ASD. Ten of these subsequently underwent a 6-week device trial in which they wore the FM system for up to 7 hours per day. RESULTS: Auditory temporal processing and spatial listening ability were poorer in subjects with ASD than in matched controls (temporal: P = .014 [95% CI -6.4 to -0.8 dB], spatial: P = .003 [1.0 to 4.4 dB]), and performance on both of these basic processing measures was correlated with speech perception ability (temporal: r = -0.44, P = .022; spatial: r = -0.50, P = .015). The provision of FM listening systems resulted in improved discrimination of speech in noise (P < .001 [11.6% to 21.7%]). Furthermore, both participant and teacher questionnaire data revealed device-related benefits across a range of evaluation categories including Effect of Background Noise (P = .036 [-60.7% to -2.8%]) and Ease of Communication (P = .019 [-40.1% to -5.0%]). Eight of the 10 participants who undertook the 6-week device trial remained consistent FM users at study completion. CONCLUSIONS: Sustained use of FM listening devices can enhance speech perception in noise, aid social interaction, and improve educational outcomes in children with ASD.

Auditory function in individuals within Leber's hereditary optic neuropathy pedigrees.

The aims of this study are to investigate whether auditory dysfunction is part of the spectrum of neurological abnormalities associated with Leber's hereditary optic neuropathy (LHON) and to determine the perceptual consequences of auditory neuropathy (AN) in affected listeners. Forty-eight subjects confirmed by genetic testing as having one of four mitochondrial mutations associated with LHON (mt11778, mtDNA14484, mtDNA14482 and mtDNA3460) participated. Thirty-two of these had lost vision, and 16 were asymptomatic at the point of data collection. While the majority of individuals showed normal sound detection, >25% (of both symptomatic and asymptomatic participants) showed electrophysiological evidence of AN with either absent or severely delayed auditory brainstem potentials. Abnormalities were observed for each of the mutations, but subjects with the mtDNA11778 type were the most affected. Auditory perception was also abnormal in both symptomatic and asymptomatic subjects, with >20% of cases showing impaired detection of auditory temporal (timing) cues and >30% showing abnormal speech perception both in quiet and in the presence of background noise. The findings of this study indicate that a relatively high proportion of individuals with the LHON genetic profile may suffer functional hearing difficulties due to neural abnormality in the central auditory pathways.