Sensorineural hearing loss in children and adults with Williams syndrome

Williams syndrome (WS) is a genetic neurodevelopmental disorder, most often accompanied by mild-to-moderate mental retardation. Individuals with WS show unique communication strengths and impairments that are challenging to treat in community, educational, and vocational settings. Many issues regarding characteristics of auditory sensitivity in WS remain to be resolved. Our purpose was to obtain behavioral (screening and pure-tone audiometry) and objective (distortion product otoacoustic emission-DPOAE) measures of auditory system function from a group of 27 individuals with WS, 6-48 years of age. These measures were gathered both at an international professional conference (n = 19) and in a clinic setting (n = 8). In the behavioral screening conditions, 16/19 (84%) of the individuals failed the hearing screening; and in the behavioral diagnostic hearing condition, 6/8 (75%) demonstrated sensorineural hearing loss (SNHL) and 1/8 demonstrated a hearing loss of undetermined type. In the objective DPOAE testing, 19/25 (76%) had DPOAE absolute amplitudes below the 5th percentile for ears with normal hearing [Gorga et al. (1997); Ear Hear 18(6):440-455]. We report SNHL in 14/18 (78%) of school-age children with WS. Post hoc analyses revealed a significant effect for age, suggesting a pattern of progressive hearing loss. An effect size analysis indicated a clinically meaningful difference in the hearing sensitivity between school-aged children and adults in the high frequencies (4,000 and 8,000 Hz). Similar hearing loss phenotype was observed in patients with familial nonsyndromic supravalvular aortic stenosis (SVAS), suggesting that molecular defects in the elastin gene in the pathogenesis of SNHL in WS. This study highlights the importance of early and regular hearing testing for WS patients and suggests that elastin may have a previously unappreciated function in maintaining hearing sensitivity.