Risk factors for hearing loss in infants under universal hearing screening program in Northern Thailand

Risk Factors Associated With Hearing Impairment in Infants and Children: A Systematic Review

The purpose of the present systematic review was to synthesize evidence on associated risk factors of hearing loss (HL) in children. Evidence-based research articles on HL published between January 2013 and December 2022 using PubMed, Cochrane, and Scopus databases were searched. The study included children between zero and three years of age who have permanent bilateral/unilateral HL (BHL/UHL) by employing case-control studies, randomized controlled trials, nonrandomized studies, prospective or retrospective cohort studies, and studies with or without comparison groups. The Newcastle-Ottawa Scale (NOS) and the Joanna Briggs Institute (JBI) critical appraisal checklist for longitudinal and cross-sectional studies were used to rate the quality of the chosen studies. The studies that would be considered were reviewed by two independent authors, and a third author was contacted if there was a dispute. A preliminary literature search uncovered 505 articles from the electronic search and 41 studies by hand searching. Duplicate records were eliminated, leaving 432 records. The abstract and title were read, and 340 studies were eliminated. There were 92 articles in total that qualified for full-text screening. Among these, 75 articles were disregarded since they lacked information or failed to assess the risk factors for HL. The qualitative synthesis, therefore, included 17 articles. Most often, cross-sectional study designs were used in the studies that were reviewed, which were then followed by longitudinal studies. Three of the studies that were reviewed used a prospective cohort design. The quality of all the included studies was rated to be good. The current review revealed that the primary statistically significant risk factors for HL included ventilator support; craniofacial anomalies; low birth weight (LBW); forceps delivery; loop diuretics; meningitis; asphyxia; intensive care; consanguinity; sepsis; Apgar scores between 0 and 4 at one minute; toxoplasmosis, other agents, rubella, cytomegalovirus, and herpes (TORCH) infections; and hyperbilirubinemia.

Cost-effectiveness analysis on implementing newborn hearing screening programmes in a low- to middle-income country

OBJECTIVE

To analyse the cost-effectiveness (CE) of implementing different newborn hearing screening protocols in a low- to middle-income country.

DESIGN

A decision analytical model with a 78-year time horizon.

STUDY SAMPLE

Direct medical, direct non-medical and indirect costs were collected from 126 subjects in southern Thailand. Various protocols involving universal newborn hearing screening (UNHS) and targeted newborn hearing screening (TNHS), using two technologies, namely automated otoacoustic emissions (aOAEs) and automated auditory brainstem responses (aABRs), were evaluated. Incremental cost-effectiveness ratios (ICERs) were calculated for all protocols in United States dollars (US$)/quality-adjusted life year (QALY) gained. Also, probabilistic sensitivity analyses with 1000 trials for each specific protocol were performed.

RESULTS

The ICERs of UNHS with aOAE, UNHS with aABR, TNHS with aABR and UNHS with optimised baseline parameters were 3702, 3545, 1545 and 2483 US$/QALY gained, respectively. With the CE threshold of 5000 US$/QALY gained, the chances of ICERs to be cost-effective for UNHS with aOAE, UNHS with aABR, TNHS with aABR and UNHS with optimised baseline parameters were 72, 77, 93 and 94%, respectively.

CONCLUSIONS

All screening protocols were considered as cost-effective, and a very high chance of being cost-effective for UNHS could be achieved when certain baseline parameters were optimised.

ASK1 is a novel molecular target for preventing aminoglycoside-induced hair cell death

Aminoglycoside antibiotics are lifesaving medicines, crucial for the treatment of chronic or drug resistant infections. However, aminoglycosides are toxic to the sensory hair cells in the inner ear. As a result, aminoglycoside-treated individuals can develop permanent hearing loss and vestibular impairment. There is considerable evidence that reactive oxygen species (ROS) production and the subsequent phosphorylation of c-Jun N-terminal kinase (JNK) and P38 mitogen-activated protein kinase (P38) drives apoptosis in aminoglycoside-treated hair cells. However, treatment strategies that directly inhibit ROS, JNK, or P38 are limited by the importance of these molecules for normal cellular function. Alternatively, the upstream regulator apoptosis signal-regulating kinase 1 (ASK1/MAP3K5) is a key mediator of ROS-induced JNK and P38 activation under pathologic but not homeostatic conditions. We investigated ASK1 as a mediator of drug-induced hair cell death using cochlear explants from Ask1 knockout mice, demonstrating that Ask1 deficiency attenuates neomycin-induced hair cell death. We then evaluated pharmacological inhibition of ASK1 with GS-444217 as a potential otoprotective therapy. GS-444217 significantly attenuated hair cell death in neomycin-treated explants but did not impact aminoglycoside efficacy against P. aeruginosa in the broth dilution test. Overall, we provide significant pre-clinical evidence that ASK1 inhibition represents a novel strategy for preventing aminoglycoside ototoxicity. KEY MESSAGES: • ASK1 is an upstream, redox-sensitive regulator of P38 and JNK, which are known mediators of hair cell death. • Ask1 knockout does not affect hair cell development in vivo, but significantly reduces aminoglycoside-induced hair cell death in vitro. • A small-molecule inhibitor of ASK1 attenuates neomycin-induced hair cell death, and does not impact antibiotic efficacy in vitro. • ASK1 may be a novel molecular target for preventing aminoglycoside-induced hearing loss.

Neonatal Hearing Screening: Prevalence of Unilateral and Bilateral Hearing Loss and Associated Risk Factors

INTRODUCTION

Newborn hearing screening is essential for early identification of hearing loss to decrease the adverse effects of hearing loss. The objective of this study was to determine the prevalence of hearing loss and risk factors of congenital hearing loss in newborns.

METHODS

In this analytical case-control study, a hearing screening test was performed for all newborns aged 3-14 days.

RESULTS

Of 5,500 newborns evaluated, 24 newborns had hearing loss. The prevalence of hearing loss was 4.36 per 1,000. Of 24 hearing-impaired newborns, 15 had bilateral hearing loss (BHL) (62.5%) and nine had unilateral hearing loss (UHL) (37.5%). Among the neonates with hearing loss, the prevalence of hearing loss was higher (77.8%) in the right ear. The main risk factors identified in this study were low gestational age (P=0.001), hospitalization in the neonatal intensive care unit (NICU) (P=0.008), exposure to ototoxic drugs (P=0.001), gestational diabetes P=0.01), craniofacial anomalies (P=0.01), convulsion (P=0.03), consanguineous marriage of parents (P=0.001), low birth weight (P=0.01), and hyperbilirubinemia (P=0.001).

CONCLUSION

The prevalence of hearing loss was higher in the right ear than in the left ear. NICU stay, use of ototoxic drugs, low gestational age (<35 weeks), gestational diabetes, craniofacial anomalies, convulsion, consanguineous marriage of parents, low birth weight, and hyperbilirubinemia were significant risk factors for congenital hearing loss in studied newborns.

Pilot implementation of newborn hearing screening programme at four hospitals in southern Thailand

OBJECTIVE

To determine the effectiveness and benefit of a universal newborn hearing screening programme at four different hospitals in southern Thailand, between January and July 2017.

METHODS

One screener per hospital recorded demographic data of all newborns and their exposure to risk of hearing loss, and evaluated their hearing by transient otoacoustic emission technology. Those who demonstrated bilateral moderate to profound hearing loss at both a first and second screening were referred for diagnostic assessment. Those with confirmed hearing loss received treatment and regular follow-up appointments, and their speech development was assessed at 1 year of age. We determined effectiveness by comparing our achieved coverage and proportion of follow-up and referrals with benchmarks set by the American Academy of Pediatrics (≥ 95%, ≥ 95% and ≤ 4%, respectively), and determined benefit by calculating the composite language scores of hearing-impaired infants who received early intervention.

FINDINGS

We screened 6140 eligible newborns, and achieved a screening coverage of 95.4% (5859/6140), lost 25.7% (63/245) and 22.0% (9/41) to follow-up at the second screening and diagnostic assessment stages, respectively, and obtained an overall proportion of referrals of 0.7% (41/6140). Twelve infants were confirmed as having hearing loss and received early intervention; nine (75%) demonstrated normal speech development by their first birthday. Our universal hearing screening yielded a prevalence of sensorineural hearing loss of less than 0.1% (3/6140).

CONCLUSION

Although ineffective by American Academy of Pediatrics standards, we demonstrated the benefit of early intervention in infants diagnosed with hearing loss.

Risk Factors for Hearing Loss and Its Prevalence in Neonates Older than 6 Months with History of Hospitalization in Intensive Care Unit

OBJECTIVES

Hearing loss is one of the most important disabilities in neonates. Delay in the detection of hearing loss leads to impaired development and may prevent the acquisition of speech. We aimed to determine the risk factors associated with hearing loss in neonatal patients aged more than 6 months with a history of hospitalization in Neonatal Intensive Care Unit (NICU).

METHODS

In this case-control study, screening for hearing loss was carried out on 325 neonates aged 6-12 months referred to Pediatric Neurology Office of Vali-e-Asr Hospital, Tehran, Iran up to 2011. Hearing loss was confirmed using Auditory Brainstem Response screening test (ABR).

RESULTS

The prevalence of mildly and moderately hearing loss in neonates was determined as 3.6%. The most significant risk factors for hearing loss in neonates were neonatal icterus associated with phototherapy, respiratory distress syndrome (RDS) and lower Apgar score.

CONCLUSION

It seems to quantitative auditory system screening using ABR is necessary for all neonates; because rehabilitation support such as speech therapy and hearing training in this age period is more effective than older ages.

Hearing loss screening tool (COBRA score) for newborns in primary care setting

Purpose

To develop and evaluate a simple screening tool to assess hearing loss in newborns. A derived score was compared with the standard clinical practice tool.

Methods

This cohort study was designed to screen the hearing of newborns using transiently evoked otoacoustic emission and auditory brain stem response, and to determine the risk factors associated with hearing loss of newborns in 3 tertiary hospitals in Northern Thailand. Data were prospectively collected from November 1, 2010 to May 31, 2012. To develop the risk score, clinical-risk indicators were measured by Poisson risk regression. The regression coefficients were transformed into item scores dividing each regression-coefficient with the smallest coefficient in the model, rounding the number to its nearest integer, and adding up to a total score.

Results

Five clinical risk factors (Craniofacial anomaly, Ototoxicity, Birth weight, family history [Relative] of congenital sensorineural hearing loss, and Apgar score) were included in our COBRA score. The screening tool detected, by area under the receiver operating characteristic curve, more than 80% of existing hearing loss. The positive-likelihood ratio of hearing loss in patients with scores of 4, 6, and 8 were 25.21 (95% confidence interval [CI], 14.69–43.26), 58.52 (95% CI, 36.26–94.44), and 51.56 (95% CI, 33.74–78.82), respectively. This result was similar to the standard tool (The Joint Committee on Infant Hearing) of 26.72 (95% CI, 20.59–34.66).

Conclusion

A simple screening tool of five predictors provides good prediction indices for newborn hearing loss, which may motivate parents to bring children for further appropriate testing and investigations.