JoAnne Whittingham

Universal newborn hearing screening: A question of evidence

The objective of this paper is to present data on the ages of diagnosis and hearing-aid fitting of children with permanent congenital or early-onset hearing loss who were identified through neonatal hearing screening (NHS) programs or medical referral. Data were collected for 709 children born between 1980 and 2003. Children who were screened were diagnosed significantly earlier (mean 6.3 months) than referred children (mean 39.5 months). For the referred children, the ages of diagnosis and amplification improved over time but remained unacceptably high. In addition, there was an inverse relationship between degree of loss and age of diagnosis, with children with lesser degrees of hearing loss identified later than those with severe to profound hearing loss. These results contribute to the evidence that NHS programs lower the ages of diagnosis and amplification and lead to earlier improved hearing. It is argued that early access to hearing should be the desired primary outcome of NHS. The numerous studies demonstrating improved ages of diagnosis resulting from NHS programs constitute adequate evidence to support these initiatives.

Mild bilateral and unilateral hearing loss in childhood: a 20-year view of hearing characteristics, and audiologic practices before and after newborn hearing screening.

Objectives: There is some evidence that the presence of even mild degrees of hearing loss and unilateral loss in early childhood can negatively affect typical development. Consequently, the identification of all children with permanent hearing loss including those with milder degrees of hearing loss is currently targeted through some newborn hearing screening initiatives. The objectives of this study were to document the proportion of children identified with mild bilateral or unilateral hearing loss (MBUHL) before and after the implementation of a universal newborn hearing screening program (UNHS). A second objective was to examine the clinical characteristics and audiologic management of this population of children. Design: This population-based study involved an analysis of data on children with hearing loss; these data had been collected prospectively over a 20-year period from 1990 to 2010 in a publicly funded pediatric teaching hospital in Canada, which provided diagnostic audiology services for all children in the region. The proportion of all children with hearing loss identified with MBUHL before and after implementation of UNHS and their clinical profiles were documented. Data related to amplification use were also retrospectively extracted from detailed medical chart reviews to investigate clinical recommendations regarding amplification and subsequent use of hearing devices. Factors affecting amplification decisions and amplification use were examined. Results: A total of 381 of 823 children (46.3%) aged 0 to 18 years who were identified with permanent nonacquired hearing loss presented with MBUHL. The proportions identified were similar in the pre- and post-UNHS periods (p = 0.207). Before UNHS children were identified at a median age of 5.0 years (interquartile range: 3.6 to 7.0) compared with a median of 0.8 years, (interquartile range: 0.3 to 2.3) post-UNHS. Progression of hearing loss was documented for 22% of all children, and for the group identified since UNHS, 32.4% experienced deterioration in hearing thresholds. Although 87.2 % of children received recommendations for amplification, more than 50% experienced considerable delay from identification to amplification. Age at identification and severity of hearing loss in the better ear were associated with amplification decisions for bilateral but not unilateral loss. Conclusions: MBUHL constitutes almost half of childhood hearing loss. UNHS has lowered age of confirmation of MBUHL by 4 to 5 years. Delay to amplification suggests uncertainty of the benefit of intervening early for these losses. Further research is required to determine the effects of early-identified MBUHL on children’s development and to document the benefits of early amplification.

Clinical practice for children with mild bilateral and unilateral hearing loss.

Objective: Historically, children with mild bilateral and unilateral hearing loss have been reported to experience difficulties related to language and academic functioning. In the context of Universal Newborn Hearing Screening, there is an increasing focus on determining optimal clinical interventions for this population of children. The objectives of this study were to determine the prevalence of mild bilateral or unilateral hearing loss identified in a clinical population from 1990 to 2006 and to document clinical practices related to recommendations and uptake of amplification. Design: This population-based study consisted of a detailed retrospective chart review of all children identified with mild bilateral or unilateral hearing loss in a Canadian pediatric center between 1990 and 2006. Hearing loss and patient characteristics were extracted to describe the clinical population. Amplification recommendations and uptake of amplification were documented. Clinical decisions regarding amplification practices were explored as a function of age of identification and severity of hearing loss. Results: A total of 670 children were identified with permanent hearing loss during the 16-yr study period, of which 291 were presented with a mild bilateral or unilateral hearing loss. Detailed reviews of the 255 available medical charts showed that at diagnosis, 178 children presented with mild bilateral, 31 with mild bilateral high frequency, and 46 with unilateral hearing loss. Eighty percent of children had been referred through conventional medical processes before the implementation of universal hearing screening and 20% had been exposed to screening. The average age of identification for the entire group was 54.2 mos (interquartile range, 30.1 to 76.9 mos). Amplification was prescribed for 91.4% of children but there was considerable delay from confirmation of hearing loss to amplification for both children identified with and without screening. Overall, 54.1% received an initial recommendation for amplification and a further 37.3% received a recommendation more than 3 mos after hearing loss confirmation. Practice patterns varied according to category of hearing loss with 60.1% of children with mild bilateral hearing loss receiving an initial recommendation compared with 26.1% of those with unilateral hearing loss. Clinical decision making relative to amplification needs was also changed during the course of audiologic care. The decision to amplify was significantly related to age at identification and degree of hearing loss in the mild bilateral group but not in the unilateral group. Although, more than 90% of children received a recommendation for amplification, chart documentation revealed that less than two thirds of children consistently used their amplification devices. Use of amplification did not vary among children with mild bilateral, mild bilateral high frequency, and unilateral hearing loss. Conclusions: This research suggests that there is considerable uncertainty related to clinical recommendations of intervention for this population of children. The impact of parental indecision regarding the benefits of amplification is unknown. Further studies are required to document the potential benefits and factors affecting amplification recommendations and use in the current practice environment where children with mild bilateral or unilateral hearing loss are identified early through newborn hearing screening.

Teachers' Perceptions of the Inclusion of Children With Hearing Loss in General Education Settings

A questionnaire was used to document the attitudes of 63 classroom teachers in Ottawa, Canada, toward inclusive education for students with hearing loss. The objective was to determine whether teachers had the attitudes, knowledge, and teaching skills proposed to underlie the effective inclusion of these students in regular classrooms. It was found that the teachers had favorable attitudes toward inclusion for students with hearing loss, felt confident in their ability to teach them, and were knowledgeable about the effects of hearing loss on language and learning. They also clearly indicated that their teacher education programs had insufficiently prepared them to teach these students effectively. The results highlight the need for increased emphasis on the unique educational requirements of students with hearing loss in teacher education programs, and for the provision of appropriate supports for both teachers and students to promote successful inclusion.

Long-term outcome after cochlear implantation in children with additional developmental disabilities

Abstract Objective: Candidacy criteria for cochlear implants have expanded to include children with complex developmental disabilities. The aim of this study was to determine the long-term benefits of cochlear implantation for this clinical population. Design: The study involved a retrospective chart review. Study sample: The review identified 21 children with complex disabilities who had received cochlear implants in a pediatric center prior to 2004. Length of cochlear implant use was between 7.3 and 19.0 years. Long-term functional auditory abilities were assessed pre and post-operatively using measures appropriate to the childs level of functioning. Cognitive assessments and developmental data were also available for the children. Results: Childrens long-term speech recognition outcomes depended highly on their developmental status. Children with severe developmental delay showed no open-set speech recognition abilities while children with mild to moderate delays achieved open-set scores ranging from 48 to 94% on open-set word testing. Five of 13 (38%) children with complex needs had discontinued use of their cochlear implant. Conclusions: Long-term speech recognition abilities following cochlear implantation for children with complex developmental issues seem to be highly related to their developmental profile. Developmental status is an important consideration in counselling families as part of the cochlear implant decision process.

Current Research with Cochlear Implants at Arizona State University

In this article we review, and discuss the clinical implications of, five projects currently underway in the Cochlear Implant Laboratory at Arizona State University. The projects are (1) norming the AzBio sentence test, (2) comparing the performance of bilateral and bimodal cochlear implant (CI) patients in realistic listening environments, (3) accounting for the benefit provided to bimodal patients by low-frequency acoustic stimulation, (4) assessing localization by bilateral hearing aid patients and the implications of that work for hearing preservation patients, and (5) studying heart rate variability as a possible measure for quantifying the stress of listening via an implant. The long-term goals of the laboratory are to improve the performance of patients fit with cochlear implants and to understand the mechanisms, physiological or electronic, that underlie changes in performance. We began our work with cochlear implant patients in the mid-1980s and received our first grant from the National Institutes of Health (NIH) for work with implanted patients in 1989. Since that date our work with cochlear implant patients has been funded continuously by the NIH. In this report we describe some of the research currently being conducted in our laboratory.

Communication Development in Early-Identified Children With Mild Bilateral and Unilateral Hearing Loss.

PURPOSE This clinical focus article provides preliminary findings from a multicenter longitudinal study investigating auditory and communication development in children with mild bilateral or unilateral hearing loss of any degree. METHOD A total of 100 children (55 with mild bilateral or unilateral hearing loss and 45 with normal hearing) underwent 1 or more assessments from a battery of auditory and language measures. RESULTS Children up to age 4 years demonstrated auditory and language skills similar to those of children with normal hearing. CONCLUSIONS Factors that affect outcomes in communication development will be explored as additional data are collected in this ongoing study.

Pediatric Cochlear Implantation: Why Do Children Receive Implants Late?

Objectives: Early cochlear implantation has been widely promoted for children who derive inadequate benefit from conventional acoustic amplification. Universal newborn hearing screening has led to earlier identification and intervention, including cochlear implantation in much of the world. The purpose of this study was to examine age and time to cochlear implantation and to understand the factors that affected late cochlear implantation in children who received cochlear implants. Design: In this population-based study, data were examined for all children who underwent cochlear implant surgery in one region of Canada from 2002 to 2013. Clinical characteristics were collected prospectively as part of a larger project examining outcomes from newborn hearing screening. For this study, audiologic details including age and severity of hearing loss at diagnosis, age at cochlear implant candidacy, and age at cochlear implantation were documented. Additional detailed medical chart information was extracted to identify the factors associated with late implantation for children who received cochlear implants more than 12 months after confirmation of hearing loss. Results: The median age of diagnosis of permanent hearing loss for 187 children was 12.6 (interquartile range: 5.5, 21.7) months, and the age of cochlear implantation over the 12-year period was highly variable with a median age of 36.2 (interquartile range: 21.4, 71.3) months. A total of 118 (63.1%) received their first implant more than 12 months after confirmation of hearing loss. Detailed analysis of clinical profiles for these 118 children revealed that late implantation could be accounted for primarily by progressive hearing loss (52.5%), complex medical conditions (16.9%), family indecision (9.3%), geographical location (5.9%), and other miscellaneous known (6.8%) and unknown factors (8.5%). Conclusions: This study confirms that despite the trend toward earlier implantation, a substantial number of children can be expected to receive their first cochlear implant well beyond their first birthday because they do not meet audiologic criteria of severe to profound hearing loss for cochlear implantation at the time of identification of permanent hearing loss. This study underscores the importance of carefully monitoring all children with permanent hearing loss to ensure that optimal intervention including cochlear implantation occurs in a timely manner.

Progressive Hearing Loss in Early Childhood.

Objectives: Deterioration in hearing thresholds in children is of concern due to the effect on language development. Before universal newborn hearing screening (UNHS), accurate information on the progression of hearing loss was difficult to obtain due to limited information on hearing loss onset. The objective of this population-based study was to document the proportion of children who experienced progressive loss in a cohort followed through a UNHS program in one region of Canada. We explored risk factors for progression including risk indicators, audiologic, and clinical characteristics of children. We also investigated deterioration in hearing as a function of age. For this study, two working definitions of progressive hearing loss were adopted: (1) a change of ≥20 dB in the 3 frequencies (500, 1000, and 2000 Hz) pure-tone average, and (2) a decrease of ≥10 dB at two or more adjacent frequencies between 500 and 4000 Hz or a decrease in 15 dB at one octave frequency in the same frequency range. Design: Population-based data were collected prospectively on a cohort of children identified from 2003 to 2013 after the implementation of UNHS. Clinical characteristics including risk indicators (as per Joint Committee on Infant Hearing), age at diagnosis, type and severity of hearing loss, and initial audiologic information were recorded when children were first identified with hearing loss. Serial audiometric results were extracted from the medical charts for this study. Differences between children with progressive and stable hearing loss were explored using &khgr;2 tests. Association between risk indicators and progressive hearing loss was assessed through logistic regression. The cumulative amount of deterioration in hearing from 1 to 4 years of age was also examined. Results: Our analysis of 330 children (251 exposed to screening) with detailed audiologic records showed that 158 (47.9%) children had some deterioration (at least ≥10 dB and) in hearing thresholds in at least one ear. The 158 children included 76 (48.1%) with ≥20 dB loss in pure-tone average in at least one ear and 82 (51.9%) with less deterioration in hearing levels (≥10 but <20 dB). In the children with progressive hearing loss, of 131 children initially diagnosed with bilateral loss, 75 (57.3%) experienced deterioration in 1 ear and 56 (112 ears; 42.7%) in both ears (total of 187 ears). Of 27 children with an initial diagnosis of unilateral loss, 25 experienced deterioration in the impaired ear and 5 in the normal-hearing ear, progressing to bilateral hearing loss. Within 4 years after diagnosis, the mean decrease in hearing for children with progressive loss was 25.9 dB (SD: 16.4) in the right ear and 28.3 dB (SD: 12.9) in the left ear. We explored the risk factors for hearing loss identified by Joint Committee on Infant Hearing where there were sufficient numbers in our sample. On multivariate analysis, there was no statistically significant relationship between most risk indicators examined (neonatal intensive care unit admission, family history, syndromes, and postnatal infections) and the likelihood of progressive loss. However, the presence of craniofacial anomalies was inversely associated with risk of progressive hearing loss (odds ratio = 0.27; 95% confidence interval: 0.10, 0.71; p = 0.01), that is, these children were more likely to have stable hearing. Conclusions: Given that almost half of the children in this cohort experienced deterioration in hearing, close postneonatal monitoring of hearing following early hearing loss identification is essential to ensure optimal amplification and therapy.

Examination of characteristics and management of children with hearing loss and autism spectrum disorders

Abstract Objective: Up to 40% of children with hearing loss present with other developmental disabilities. The purpose of this study was to document the prevalence of autism spectrum disorders (ASD) in children with permanent hearing loss, to describe the audiologic characteristics, and to examine clinical management. Design: Prospective data related to clinical characteristics of children identified with hearing loss and ASD were examined. A retrospective chart review was also conducted to explore clinical management and uptake of amplification. Study sample: The study included all children in one Canadian region identified with permanent hearing loss and followed from 2002–2010. Results: Of a total of 785 children with permanent hearing loss, 2.2% (n = 17) also received a diagnosis of ASD. The 13 boys and 4 girls presented with a range of audiologic profiles from unilateral to profound bilateral hearing loss. Four of five children with unilateral hearing loss experienced progression to bilateral loss. Amplification was recommended for all but one child and 9 of 16 children continued to use their hearing devices. Conclusions: The higher prevalence rate of ASD in this clinical population is consistent with previous reports. Our findings suggest that some children with autism can derive benefits from the use of amplification.