Children with ANSD fitted with hearing aids applying the AAA Pediatric Amplification Guideline: Current Practice and Outcomes

Background— Up to 15% of children with permanent hearing loss have auditory neuropathy spectrum disorder (ANSD), which involves normal outer hair cell function and disordered afferent neural activity in the auditory nerve or brainstem. Given the varying presentations of ANSD in children, there is a need for more evidence-based research on appropriate clinical interventions for this population. Purpose— This study compared the speech production, speech perception, and language outcomes of children with auditory neuropathy spectrum disorder (ANSD) who are hard of hearing and children with similar degrees of mild to moderately-severe sensorineural hearing loss (SNHL), all of whom were fitted with bilateral hearing aids based on the American Academy of Audiology (AAA) pediatric amplification guidelines. Research design— Speech perception and communication outcomes data were gathered in a prospective accelerated longitudinal design, with entry into the study between six months and seven years of age. Three sites were involved in participant recruitment: Boys Town National Research Hospital, the University of North Carolina at Chapel Hill, and the University of Iowa. Study sample: The sample consisted of 12 children with ANSD and 22 children with SNHL. The groups were matched based on better-ear pure-tone average, better-ear aided speech intelligibility index, gender, maternal education level, and newborn hearing screening result (i.e., pass or refer). Data collection and analysis— Children and their families participated in an initial baseline visit, followed by visits twice a year for children under age 2 years and once a year for children older than 2 years. Paired-sample t-tests were used to compare children with ANSD to children with SNHL. Results— Paired t-tests indicated no significant differences between the ANSD and SNHL groups on language and articulation measures. Children with ANSD displayed functional speech perception skills in quiet. Although the number of participants was too small to conduct statistical analyses for speech perception testing, there appeared to be a trend in which the ANSD group performed more poorly in background noise with hearing aids, compared to the SNHL group. Conclusions— The AAA Pediatric Amplification Guidelines recommend that children with ANSD receive a hearing aid trial if their behavioral thresholds are sufficiently high enough to impede speech perception at conversational levels. For children with ANSD in the mild to severe hearing loss range, the current results support that recommendation, as children with ANSD can achieve functional outcomes similar to peers with SNHL. The results of the study showed no significant differences between children with ANSD and SNHL in terms of outcomes in a variety of different domains. The two groups well-matched on a number of chronological age, degree hearing loss, aided audibility, maternal education level, gender, and NHS status. The groups were not matched on birth history – the ANSD group birth than the SNHL group, did not have effect on group-level comparisons, without adjusting age-based standard scores for prematurity. SNHL,