Changes in prevalence, aetiology, age at detection, and associated disabilities in preschool children with hearing impairment born in Göteborg

Main outcomes from the first two years of France's screening programme for neonatal permanent hearing loss through a descriptive study

AIM

This study aimed to evaluate the implementation of France's neonatal hearing loss screening programme two years after its launch, and to estimate permanent bilateral neonatal hearing loss (PBNHL) prevalence and distribution by severity.

METHODS

This descriptive study used aggregated regional data on all births in France in 2015-2016. Screening coverage, refusal rate, positive predictive value (PPV), proportion of children with suspected PBNHL, PBNHL prevalence and distribution by severity were calculated.

RESULTS

800,000 neonates were eligible for the screening programme per year. Between 2015 and 2016, screening coverage increased (83.3 vs 93.8%; p<0.001), and the refusal rate remained stable (0.1%). In 2016, when considering the additional tests performed several weeks after birth, the proportion of suspected PBNHL neonates decreased (1.4 vs 0.9%) while the PPV increased (4.7 vs 7.6%). In 2015, the estimated prevalence of PBNHL (moderate to profound) was 0.09% (95% CI 0.08-0.10). Among neonates with >=41 decibels deficit, 56.8%, 16.6%, and 26.6% had moderate, severe and profound hearing loss, respectively.

CONCLUSION

The national target of 90% screening coverage was exceeded. The additional test could be useful to avoid overcrowding in diagnostic structures. Diagnostic data quality must be improved to confirm PBNHL prevalence and distribution by severity.

A Two-Interval, Forced-Choice, Observer-Based Procedure for Evaluating Hearing Sensitivity in Children With Motor and Developmental Impairments

Purpose It can be challenging to collect reliable behavioral responses to sound from individuals with significant motor or developmental impairments, the most common types of comorbid disability found in children with hearing loss (e.g., Gallaudet Research Institute, 2011). The purpose of this study was to test the feasibility of using a 2-interval, forced-choice, observer-based method for individuals considered to be difficult-to-test using behavioral audiometric assessments. Method Participants were 5 children with motor and developmental impairments, ages 5-15 years (M = 11.6, SD = 4.6). The functional abilities of all participants were greater than 2 SDs below the mean, as measured by the Vineland-II Parent Caregiver Rating Form. Participants listened to either a male talker saying the word "playground" or a 1000-Hz warble tone, presented via an insert earphone or a sound field speaker. An observer, blind to signal presentation, selected 1 of 2 temporal intervals, determining which contained the signal based only on participant behavior. Criterion was reached when the observer correctly identified the interval containing the signal for 8 of the last 10 trials. Results An 80%-correct criterion was met for all participants, suggesting feasibility for use in children with motor or developmental impairment. Two participants were tested using an adaptive tracking procedure; a reliable threshold estimate was obtained for both children. This method offers promise for children who have difficulty performing behavioral audiometric assessments currently in use clinically.

Hearing loss in urban South African school children (grade 1 to 3)

OBJECTIVE

This study aimed to describe the prevalence and characteristics of hearing loss in school-aged children in an urban South African population.

METHOD

Children from grade one to three from five schools in the Gauteng Province of South Africa formed a representative sample for this study. All children underwent otoscopic examinations, tympanometry and pure tone screening (25dB HL at 1, 2 and 4kHz). Children who failed the screening test and 5% of those who passed the screening test underwent diagnostic audiometry.

RESULTS

A total of 1070 children were screened. Otoscopic examinations revealed that a total of 6.6% ears had cerumen and 7.5% of ears presented with a type-B tympanogram. 24 children (12 male, 12 female) were diagnosed with hearing loss. The overall prevalence of hearing loss was 2.2% with Caucasian children being 2.9 times more (95% confidence interval, 1.2-6.9) likely to have a hearing loss than African children.

CONCLUSION

Hearing loss prevalence in urban South African school-aged children suggest that many children (2.2%) are in need of some form of follow-up services, most for medical intervention (1.2%) with a smaller population requiring audiological intervention (0.4%).

Hearing and speech impairment at age 4 and risk of later non-affective psychosis

BACKGROUND

Schizophrenia often becomes manifest in late adolescence and young adulthood but deviations in physical and behavioural development may already be present in childhood. We investigated the relationship between hearing impairment (measured with audiometry) and speech impairment (broadly defined) at age 4 years and adult risk of non-affective psychosis.

METHOD

We performed a population-based, case–control study in Sweden with 105 cases of schizophrenia or other non-affective psychoses and 213 controls matched for sex, date and place of birth. Information on hearing and speech impairment at age 4, along with potential confounding factors, was retrieved from Well Baby Clinic (WBC) records.

RESULTS

Hearing impairment [odds ratio (OR) 6.0, 95% confidence interval (CI) 1.6–23.2] and speech impairment (OR 2.6, 95% CI 1.4–4.9) at age 4 were associated with an increased risk of non-affective psychotic illness. These associations were mutually independent and not explained by parental psychiatric history, occupational class or obstetric complications.

CONCLUSIONS

These results support the hypothesis that psychosis has a developmental aspect with presentation of antecedent markers early in childhood, long before the disease becomes manifest. Our findings add to the growing evidence that early hearing impairment and speech impairment are risk indicators for later non-affective psychosis and possibly represent aetiological clues and potentially modifiable risk factors. Notably, speech impairment and language impairment are both detectable with inexpensive, easily accessible screening.

Hearing impairments among Saudi preschool children

BACKGROUND

Hearing loss among school-entrant children in the developing world has been widely reported as a significant health problem. Failure to detect hearing loss, either congenital or acquired, in children may result in lifelong deficits in speech and language acquisition. The aims of this study were: (1) to estimate the prevalence of hearing loss and (2) to identify its different types.

METHODS

This is a cross-sectional study that included all children (n=2574) aged 4-8 years who attended the obligatory health examination for kindergarten (=370) and primary school (n=2204) entry at the school health center of King Abdulaziz Medical City, Riyadh, Saudi Arabia, from March 2009 to December 2010. Pure-tone air conduction audiometry was conducted for each child in a sound-treated room followed by a diagnostic test. Tympanometry was performed as a complement to the overall objectives of a hearing screening program.

RESULTS

A total of 45 children were diagnosed with hearing impairment (84.4% conductive and 15.6% sensori-neural), with an overall prevalence of 1.75% (95% C.I.: 1.25, 2.25). The majority of cases were females (71.1%), of school age (80.0%), with conductive deafness (84.4%). More than one-half of cases had bilateral deafness (55.6%) of mild degree (57.8%). As for conductive deafness, otitis media with effusion ranked first as a cause of deafness (34.9%), followed by wax and chronic otitis media (23.3% each), while traumatic perforated drum came last (2.3%). Sensorineural deafness constituted 16.2% of all cases.

CONCLUSION

Conductive hearing loss is the primary type of hearing loss among children and is easy to correct. The urgent development of audiological services in other school health centers in the country, particularly those with good referral systems to Ministry of Health hospitals, is needed. Evidence-based guidelines to identify, monitor, and manage otitis media with effusion (OME) in children in the primary healthcare setting and a strategy to prevent hearing loss are recommended.

The association between short stature and sensorineural hearing loss

In order to test the Thrifty Phenotype Hypothesis on hearing, data from two cross-sectional studies on hearing were re-evaluated. The data sets comprised 500 18-year-old conscripts, and 483 noise-exposed male employees. Sensorineural hearing loss (SNHL) was over-represented among conscripts with a short stature (odds ratio=2.2) or hearing loss in the family (odds ration=4.2), but not among noise-exposed conscripts (odds ratio=0.9-1.3). Among noise-exposed short employees, hypertension and age exhibited a negative impact on high frequency hearing thresholds, while among tall employees hypertension had no effect on hearing and the influence of age was less pronounced (p<0.01 for body height; p<0.02 for age, hypertension and the interaction between body height and hypertension; p<0.05 for the interaction between body height and age). This suggests that mechanisms linked to fetal programming and growth retardation and/or insulin-like growth factor 1 levels during fetal life, such as a delayed cell cycle during the time window when the cochlea develops, may cause SNHL in adulthood.

Study of the hearing loss in children and adolescents, comparing the periods of 1990-1994 and 1994-2000

INTRODUCTION

In 1994, a study was performed with 200 children and adolescents suffering from hearing loss. It concluded that the diagnostic confirmation of hearing loss within 2 years of age occurred in just 13% of the cases, although 56% were suspected in that phase. The loss of time of over 2 years between suspicion and confirmation of hearing loss occurred in 42% of the cases.

OBJECTIVES

The comparison of the main hearing loss etiologies-genetic cause, consanguinity, congenital rubella, meningitis, perinatal events and unknown causes-in children and adolescents in the periods of 1990-1994 and 1994-2000; comparison of incidence, in males and females, for each etiology and among the others; comparison of age at the first consultation, for each and among them; and the investigation as to whether the time between suspicion and diagnosis of hearing loss was different for each etiology and among the others.

METHODS

During the period of 1990-2000, of the 519 children and adolescents with hearing loss, 442 individuals were selected, in the two moments of the study: 1990-1994 and 1994-2000. The variables used were: sex, age at first consultation, suspected etiology and time between suspicion and confirmation of hearing loss.

RESULTS

Congenital rubella, genetic and perinatal causes, meningitis, consanguinity and unknown causes were responsible for over 80% of all etiologies, in both periods. There were no differences between the sexes in the periods studied. There was no relation among age, sex and etiology. Among the etiologies studied, there were no differences in the lengths of times between suspicion and confirmation of hearing loss, in each period separately. The comparative study showed that congenital rubella, genetic and unknown causes took longer times between suspicion and confirmation of hearing loss, for the period of 1990-1994, as compared with 1994-2000.

CONCLUSIONS

Congenital rubella remains as an important etiology, as well post-meningitis deafness. Age at first consultation did not show relationship to the hearing loss etiology nor to sex. Independently of whether the etiology being pre-natal, perinatal or post-natal, congenital or acquired, the length of time between suspicion and confirmation of hearing loss did not differ between the periods studied, separately.

Mumps in Poland since 1990 to 2003; epidemiology and antibody prevalence

The annual incidence of mumps in Poland over the period 1990-2003 was 45-570 per 100,000 population with the epidemic peak every 4-5 years. Till 2003, mumps vaccination has not been included in the part of National Immunisation Program in Poland that comprises the obligatory vaccinations. However, mumps vaccination was recommended by National Health Authority for children at the second year of life and it could be obtained privately. The proportion of vaccinated children has increased by 50% in last years. It has influenced on decreasing of number of notified mumps cases in Poland, on lengthening of inter-epidemic period as well as on drift of infections towards older groups of children. The results of serological survey carried out on 1390 serum samples have indicated, that the proportion of positive serum samples (>11 VE/ml) was only 24.1% for children aged 1-4 years, 45.4% for children aged 5-9 years, 72.5% for age group 10-14 years, and over 85% for persons aged 15-30 years. Epidemiological data and the high proportion of individuals with negative titres of specific mumps IgG antibodies justify the need of introduction of obligatory mass immunisation against mumps in Poland.

A population-based study of the recurrence of developmental disabilities--Metropolitan Atlanta Developmental Disabilities Surveillance Program, 1991-94

Serious developmental disabilities (DD) are quite common and affect approximately 2% of all school-aged children. The impact of DDs with respect to the need for special education services, medical care and the demand on family members can be enormous. While this impact can be magnified for families with more than one child with a DD, little is known regarding the epidemiology of recurrence of DDs. When the cause of a DD is unknown, genetic counsellors rely on recurrence risk estimates which for DDs are over 10 years old. The objectives of our study were to: (1) assess the contribution of recurrent cases to the prevalence of DDs; (2) provide current, population-based recurrence risk estimates; and (3) examine characteristics of the first affected child as predictors of recurrence. Two population-based data sources were used to identify all children born to the same mother during the period 1981-91 in the five-county metropolitan Atlanta area with at least one of four DDs: mental retardation (MR), cerebral palsy, hearing loss, or vision impairment. Recurrence risk estimates for these DDs ranged from 3% to 7% and were many times higher than the background prevalences. The risk of recurrence of DDs was greatest for MR - approximately eight times greater than the baseline MR prevalence. Isolated mild MR (IQ 50-70) was highly concordant between siblings with MR. Sex, race, and birthweight of the index child, maternal education, and maternal age were not significantly associated with recurrence risk. Further research is needed to investigate the roles of genetic and environmental factors on the recurrence of DDs, particularly isolated mild MR.

Epidemiology of the UK population of hearing-impaired children, including characteristics of those with and without cochlear implants--audiology, aetiology, comorbidity and affluence

This study reports epidemiological data for 17,160 children with permanent bilateral hearing impairment >40 dB in the UK in the birth cohorts 1980-95 inclusive. Children were uniquely ascertained from notifications from professionals in health and education. Results indicate a changing aetiological profile over birth cohort. The percentage of unknown aetiologies and those of prenatal or postnatal origin have decreased, while syndromal and perinatal aetiologies have increased, with no change in genetic aetiologies. Nearly 30% of hearing-impaired children have another disability in addition to their hearing impairment. Children with cochlear implants are more likely than other profoundly impaired children to have a postnatal aetiology and less likely to have disabilities concerned with learning or cognition. A proxy measure of affluence indicates that significantly more profoundly impaired children in more affluent families receive cochlear implants than do those in less affluent families. These findings provide baseline data for the UK population and raise questions of widespread relevance for future research.

Prevalence and characteristics of children with serious hearing impairment in metropolitan Atlanta, 1991-1993

OBJECTIVES

There is a paucity of data describing the epidemiology of serious hearing impairment among children in the United States. This report provides information on the prevalence of serious hearing impairment among children born in the 1980s and living in the metropolitan Atlanta area in 1991-1993 and on the characteristics of children with serious hearing impairment.

METHODS

Data for this report are drawn from the Metropolitan Atlanta Developmental Disabilities Surveillance Program, an ongoing, active case-ascertainment system for mental retardation, cerebral palsy, hearing impairment, and vision impairment among children 3 to 10 years of age. Hearing impairment was defined as a bilateral, pure-tone hearing loss at frequencies of 500, 1000, and 2000 Hz averaging 40 decibels or more, unaided, in the better ear. Both severity and type of hearing loss were examined. Cross-sectional as well as birth cohort prevalence rates of serious hearing impairment were computed by sex and by race. The presence of mental retardation, cerebral palsy, vision impairment, or a seizure disorder was also assessed. An attempt was made to determine the probable etiology of a subset of the cases.

RESULTS

The average, annual prevalence rate for moderate to profound hearing loss was 1.1 per 1000. The prevalence rate increased steadily with age. Ninety percent of all cases for which the type of loss was recorded were sensorineural. The highest rate was seen among black male children (1.4 per 1000). Thirty percent of case children had another neurodevelopmental condition, most frequently mental retardation. Black male children also experienced the highest rate of presumed congenital hearing impairment. The mean age at which children with presumed congenital hearing impairment first met the surveillance case definition was 2. 9 years. A probable etiology could only be found for 22% of cases born in the study area.

CONCLUSIONS

The data presented here provide information on the descriptive epidemiology of serious hearing impairment among United States children. The reasons for the higher rates among black children, especially males, may be a fruitful direction for further research.