Detecting Hearing Loss Through Targeted Surveillance: Risk Registry and Surveillance Timeframe Recommendations.

PURPOSE: The purpose of this study was to inform the revision of a targeted surveillance risk registry by identifying which risk factors predict postnatally identified hearing loss (PNIHL) in children who pass newborn hearing screening and to determine whether hearing surveillance beyond the age of 1 year is warranted. METHOD: We used retrospective analysis of the audiological outcomes of children born in the state of Queensland, Australia, between January 1, 2010, and December 31, 2019, who passed the newborn hearing screen with risk factors. RESULTS: Approximately one third of children were lost to follow-up and could not be included in the analysis. Risk factors that predicted PNIHL in the analyzed cohort were as follows: syndromes associated with hearing loss, craniofacial anomalies, perinatal infections, and family history of permanent childhood hearing loss. Severe asphyxia did not predict PNIHL but yielded some cases of significant bilateral hearing loss. Hearing loss in children with a history of prolonged ventilation was mild and/or unilateral in nature (except in cases where the hearing loss was due to an unrelated etiology). There were no cases of PNIHL in children with hyperbilirubinemia or neonatal bacterial meningitis. For the risk factors that predicted PNIHL, nearly all hearing losses were detected by 1 year of age, except for children with family history where one quarter of hearing losses had a later onset. CONCLUSIONS: The four risk factors recommended for efficient postnatal identification of hearing loss are as follows: syndromes associated with hearing loss, craniofacial anomalies, perinatal infection, and family history of permanent childhood hearing loss. Hearing surveillance through to 1 year old is sufficient except for children with a family history, where a second phase assessment is indicated. Alternative targeted surveillance protocols and models of care are required to minimize loss to follow-up.

Childhood hearing loss detected beyond the newborn screen.

OBJECTIVE: To understand the characteristics of postnatal hearing loss (PNHL) identified via different referral pathways, to inform childhood hearing screening and referral practices. DESIGN: Retrospective analysis of screening and audiology records. STUDY SAMPLE: A cohort of 385 children who passed newborn hearing screening in Queensland, Australia between September 2004 and December 2017 and were later diagnosed with permanent hearing loss. RESULTS: Neonatally identified risk factors facilitated detection for half the cohort, with PNHL detected earlier (average age of 31 months) and at a milder degree. PNHL was detected at an average age of 49 months via other pathways. Proportions of bilateral moderate or greater PNHL were greatest in children with significant medical circumstances (60.7%) and those with noted delays or concerns (39.2%), whereas childhood hearing screening programs detected greater proportions of unilateral moderate or greater PNHL (47.4%). CONCLUSIONS: Risk-factor-based surveillance detects PNHL early but does not detect all cases. Screening children with speech and language delays, parental or professional concern, or with relevant medical circumstances (eg meningitis or chemotherapy) is warranted based on the types of PNHL detected. Further evidence may be required to justify the rollout of postnatal population childhood screening programs.

Neonatal bacterial meningitis: hearing screening and audiological monitoring outcomes.

OBJECTIVE: This study reviewed the outcomes of universal newborn hearing screening (UNHS) and ongoing hearing monitoring in children following recovery from neonatal bacterial meningitis to determine (a) whether screening may be a suitable alternative to diagnostic audiology for detecting permanent childhood hearing loss (PCHL) and (b) whether infants who pass UNHS should be monitored throughout childhood. DESIGN: Retrospective analysis of a UNHS database. STUDY SAMPLE: Data were extracted from the state-wide UNHS database for all children born in Queensland Australia between 1 September 2004 and 30 June 2020 with the risk factor of bacterial meningitis (in isolation or in combination with other risk factors) identified at the time of the UNHS. This cohort included 231 children. RESULTS: Results showed that all post-meningitic infants diagnosed with PCHL had a refer result on the UNHS or were medically excluded from screening. Additionally, no cases of PCHL were identified through the targeted surveillance program following a pass result on UNHS. CONCLUSIONS: UNHS may be sufficient to detect PCHL in post-meningitic neonates and routine audiological monitoring may not be required for children who pass the screen.

Cochlear nerve deficiency is an important cause of auditory neuropathy spectrum disorder at a population level in children.

OBJECTIVES: To determine the incidence, prevalence and describe risk factors and etiology for childhood Auditory Neuropathy Spectrum Disorder using population level data from a statewide universal newborn hearing program. METHODS: A retrospective statewide universal newborn hearing screening database review and descriptive analysis from 2012 to 2019 of demographic, risk factors and hearing loss etiology for babies with sensorineural hearing loss and ANSD was completed. A 2 stage aABR protocol was used and ANSD was classified when click evoked ABR were absent or grossly abnormal but otoacoustic emissions and or cochlear microphonics were present. Medical evaluation and investigation by a pediatrician or otolaryngologist was performed and etiology was assigned using a coding scheme. Next generation genetic sequencing was not available. RESULTS: From 2012 to 2019, 487 636 babies were screened for congenital hearing loss (99.1%) and 1150 were confirmed to have permanent SNHL, 80 of whom were diagnosed with ANSD (52 unilateral and 28 bilateral). The prevalence of ANSD was 7.0% and population prevalence was 0.16 per 1000 live births. The only demographic or risk factor significantly more likely to be associated with ANSD than SNHL was hyperbilirubinemia. The most common etiology for ANSD was hypoplasia or absence of the cochlear nerve with 37 cases (46.3%), and it was significantly more likely with unilateral than bilateral ANSD. CONCLUSION: At a population level, ANSD was more likely to be unilateral and the only perinatal risk factor significantly associated was hyperbilirubinemia. Cochlear nerve deficiency was the most common etiology. Given that this can occur in well babies, this provides further evidence for aABR as a preferred mode for newborn hearing screening.

Aetiology of permanent childhood hearing loss at a population level.

AIM: To evaluate and describe results of aetiological investigations offered to a population level cohort of babies who had confirmed permanent hearing loss after they either (i) failed universal neonatal hearing screening or (ii) passed newborn screening but were detected with a permanent hearing loss in early childhood. METHODS: Descriptive analysis of results of investigations offered to neonates and young children in whom permanent hearing loss was detected as part of a statewide newborn hearing screening programme. A total of 306 285 newborns were screened between 2013 and 2017. The failed screening results were confirmed by a diagnostic audiological assessment battery. Medical evaluation for the identification of the cause of the hearing loss was performed by a paediatrician or otolaryngologist, investigations were ordered using a stepwise approach, and aetiology was assigned using a coding scheme. RESULTS: Permanent hearing loss was confirmed in 967 children (0.3%). Data were available for 873. An aetiological factor was identified or presumed in 61.3% of cases. Genetic causes were present in 26.8% and structural causes were present in 24.9% of cases. Congenital cytomegalovirus was present in 4.4%. CONCLUSIONS: Use of a coding scheme is feasible at a population level and allows collation of data from multiple sites and will allow outcome mapping and service planning.

Predicting hearing loss from 10 years of universal newborn hearing screening results and risk factors.

OBJECTIVE: This study investigated whether demographic variables, risk factor presence or absence and universal newborn hearing screening (UNHS) results can be used to predict permanent childhood hearing loss (PCHL) in infants referred from screening. DESIGN: Retrospective analysis of a UNHS database. STUDY SAMPLE: Data were extracted from the state-wide UNHS database storing details of the 613,027 infants who were born in Queensland, Australia between 1 January 2007 and 31 December 2016 and participated in UNHS. This study included the 6735 children who were referred from the UNHS program for diagnostic audiology due to failing the screen in one or both ears or bypassing screening. RESULTS: Factors with a significant positive association with PCHL that were incorporated into a logistic regression model were: female gender, non-indigenous status, family history of PCHL, craniofacial anomalies and syndromes associated with PCHL, and a bilateral refer result on screening. CONCLUSIONS: Odds of PCHL vary among infants referred for diagnostic assessment from UNHS programs. When an infant refers on the newborn hearing screen, information about their gender, indigenous status, identified risk factors and specific screening outcome can be used to predict the likelihood of a congenital PCHL diagnosis.