Australian families of deaf and hard of hearing children: Are they using sign?

BACKGROUND: Deaf and hard of hearing (DHH) children may experience communication delays, irrespective of early intervention and technology. Australian Sign Language (Auslan) is one approach in early intervention to address language delays. Current prevalence of Auslan use among Australian families with DHH children is unknown. AIMS: The first aim was to determine the proportion of families enrolled in an Australian statewide hearing loss databank who use Auslan with their DHH child. The second aim was to explore the relationships between indicators of child hearing loss (bilateral or unilateral hearing loss, degree of hearing loss, and device use: hearing aids and cochlear implants), family factors (maternal education, attendance at early intervention, family history of deafness, and socio-economic disadvantage) and the family's reported use of Auslan. METHODS: We analysed the enrolment data from 997 families who participated in an Australian statewide hearing loss databank between 2012 and 2021. We described the proportion of families who used Auslan with their DHH child at home. The association between indicators of child hearing loss and family factors, and the parental reports of communication approach were examined using correlation analyses. RESULTS: Eighty-seven of 997 parents (8.7%) reported using Auslan with their DHH child. Of these, 26 (2.6%) used Auslan as their primary language. The use of Auslan at home was associated with the following indicators of child hearing loss: bilateral hearing loss, profound compared to mild hearing loss, and cochlear implant and hearing aid use compared to no device use. The family factors associated with the use of Auslan were: referral or attendance at early intervention compared to those who did not attend, and a family history of deafness compared to those with none. No association was found between maternal education and socio-economic disadvantage and the use of Auslan. CONCLUSION: This Australian study found a low proportion (8.7%) of families with a DHH child who reported using Auslan. Seven child hearing loss and family factors were considered, and five were significantly associated with using Auslan at home. Children with a greater degree of hearing loss, attendance at early intervention and family history of deafness tended to use Auslan.

Speech and language in DDX3X-neurodevelopmental disorder: A call for early augmentative and alternative communication intervention.

Pathogenic variants in DDX3X are associated with neurodevelopmental disorders. Communication impairments are commonly reported, yet specific speech and language diagnoses have not been delineated, preventing prognostic counseling and targeted therapies. Here, we characterized speech and language in 38 female individuals, aged 1.69-24.34 years, with pathogenic and likely pathogenic DDX3X variants (missense, n = 13; nonsense, n = 12; frameshift, n = 7; splice site, n = 3; synonymous, n = 2; deletion, n = 1). Standardized speech, language, motor, social, and adaptive behavior assessments were administered. All participants had gross motor deficits in infancy (34/34), and fine motor deficits were common throughout childhood (94%; 32/34). Intellectual disability was reported in 86% (24/28) of participants over 4 years of age. Expressive, receptive, and social communication skills were, on average, severely impaired. However, receptive language was significantly stronger than expressive language ability. Over half of the assessed participants were minimally verbal (66%; 22/33; range = 2 years 2 months-24 years 4 months; mean = 8 years; SD = 6 years) and augmented speech with sign language, gestures, or digital devices. A quarter of the cohort had childhood apraxia of speech (25%; 9/36). Despite speech and language impairments, social motivation was a relevant strength. Many participants used augmentative and alternative communication (AAC), underscoring the need for early, tailored, and comprehensive AAC intervention.

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.

Genetic aetiologies for childhood speech disorder: novel pathways co-expressed during brain development.

Childhood apraxia of speech (CAS), the prototypic severe childhood speech disorder, is characterized by motor programming and planning deficits. Genetic factors make substantive contributions to CAS aetiology, with a monogenic pathogenic variant identified in a third of cases, implicating around 20 single genes to date. Here we aimed to identify molecular causation in 70 unrelated probands ascertained with CAS. We performed trio genome sequencing. Our bioinformatic analysis examined single nucleotide, indel, copy number, structural and short tandem repeat variants. We prioritised appropriate variants arising de novo or inherited that were expected to be damaging based on in silico predictions. We identified high confidence variants in 18/70 (26%) probands, almost doubling the current number of candidate genes for CAS. Three of the 18 variants affected SETBP1, SETD1A and DDX3X, thus confirming their roles in CAS, while the remaining 15 occurred in genes not previously associated with this disorder. Fifteen variants arose de novo and three were inherited. We provide further novel insights into the biology of child speech disorder, highlighting the roles of chromatin organization and gene regulation in CAS, and confirm that genes involved in CAS are co-expressed during brain development. Our findings confirm a diagnostic yield comparable to, or even higher, than other neurodevelopmental disorders with substantial de novo variant burden. Data also support the increasingly recognised overlaps between genes conferring risk for a range of neurodevelopmental disorders. Understanding the aetiological basis of CAS is critical to end the diagnostic odyssey and ensure affected individuals are poised for precision medicine trials.