Prevalence of hearing loss in children living in low- and middle-income countries over the last 10 years: A systematic review.

AIM: To summarize the literature on the prevalence of pediatric hearing loss in low- and middle-income countries (LMICs). METHOD: A systematic review initially identified 2833 studies, of which 122 met the criteria for inclusion. Eighty-six of those studies included diagnoses and were included in a meta-analysis. RESULTS: The meta-analysis indicated a 1% (95% confidence interval = 0.8-2.0) prevalence of childhood hearing loss across LMICs. There was significant heterogeneity between studies and evidence of publication bias. The prevalence of mild and moderate cases of hearing loss was higher than more severe cases and there were fewer cases of mixed hearing loss compared to conductive or sensorineural hearing loss. No differences were identified between the prevalence of unilateral versus bilateral hearing loss or hearing loss according to sex. The quality of the studies, age of participants, and location of data collection may have influenced the results. High variability in the reporting of etiology made the causes of hearing loss unclear. INTERPRETATION: The literature indicates that 1% of children in LMICs have hearing losses. However, most studies missed children with acquired hearing loss, which may lead to under-reporting of global prevalence. This systematic review is an initial step toward developing and implementing population-appropriate treatment and prevention programs for childhood hearing loss in LMICs. WHAT THIS PAPER ADDS: The prevalence of childhood hearing loss in low- and middle-income countries is 1%. Reporting of hearing loss etiology was highly variable.

A survey of pediatric cochlear implant recipients as young adults.

OBJECTIVES: To identify the influence of pediatric cochlear implantation on long term communication modality, education, and income. METHODS: A telephone survey was conducted with 56 young adults who had received cochlear implants (CI) as children. The participants were, on average, 10.6 (SD = 64) when they received their CI and 21 (SD = 2.29) when they participated in this study. All of the participants used a unilateral CI at the time of the survey. Where applicable, survey results were compared to the general population of similar aged individuals in Ontario using chi-squared tests of proportionality. RESULTS: Participants (49/56, 88%) indicated that they used their CI all waking hours and 75% (42/56) reported using spoken language as their primary mode of communication. They attended post-secondary school at higher rates than the general population (χ2(1) = 14.35, p < .001); a wide range of study areas were identified with a greater proportion involved in fine arts than the general population (χ2(1) = 25.50, p < .001). The rates of employment in this group were below general rates (χ2(1) = 21.87, p < .001). However, those who were employed reported salaries similar to their hearing peers. CONCLUSION: The findings from this study suggest that young adults who received a unilateral CI in childhood typically continue to use their CIs to support spoken language. Their increased rates of post-secondary education are encouraging and they may be choosing unique areas of study. Longer term studies are required to further investigate lower rates of employment in this cohort.

Cochlear Implant Use Remains Consistent Over Time in Children With Single-Sided Deafness.

OBJECTIVES: To measure the acceptance of a cochlear implant by children with single-sided deafness (SSD) using datalogging technology in the cochlear implant processor. DESIGN: Datalogs from follow-up clinical audiology appointments for 23 children with SSD were extracted from their cochlear implant processors ranging from 1 to 8 visits (M = 3.74, SD = 1.79). The number of hours the cochlear implant was in use per day, the number of times the coil disconnected from the internal device, and the percentage of daily cochlear implant use in different auditory environments were collected from the datalogs. Linear mixed-effects regressions were used to analyze the relationship between age, hearing experience, cochlear implant use, and coil-offs per day. Nonlinear regressions were conducted to evaluate cochlear implant use in different environments. RESULTS: Children with SSD wore their cochlear implants for 6.22 (SD = 2.81; range = 0.0004 to 14.74) hours per day on average. No significant change in cochlear implant use was seen as the children grew older or gained more hearing experience. As hearing experience increased, the number of coil-offs per day was reduced. Preschoolers spent more time in "music" and "speech" and less time in "noise" and "quiet" than older and younger children while older children spent more time in "speech-in-noise." CONCLUSIONS: Children with SSD consistently wear their cochlear implants. However, the auditory environments to which they are exposed vary over time. Regular cochlear implant use by this population suggests that it does not detract from a normal-hearing ear and that children with SSD appreciate access to bilateral input.