Prevalence of childhood hearing impairment of different severities in urban and rural areas: a nationwide population-based study in Taiwan

A systematic review of the prevalence of late identified hearing loss in childhood

OBJECTIVES

The objective of this systematic review was to assess the evidence about the prevalence of permanent hearing loss for children not identified from newborn hearing screening (NHS).

DESIGN

Articles were grouped into three categories based on the methodological approach: (1) all participants received diagnostic testing, (2) otoacoustic emission (OAE) or pure tone screening was completed and those not passing were referred for a diagnostic test, and (3) data were retrieved from archival records. Study characteristics, prevalence, and contextual factors were synthesised and narratively described.

STUDY SAMPLE

30 peer-reviewed articles.

RESULTS

Prevalence of permanent hearing loss per 1,000 children ranged from 0.32 to 77.87 (M = 7.30; SD = 16.87). Variations in the criteria for inclusion contributed to prevalence differences. Prevalence was higher when unilateral and milder degrees of hearing loss were included, and older children had higher prevalence (M = 13.71; SD = 23.21) than younger children (M = 1.57; SD = 0.86).

CONCLUSION

There is scant research on prevalence of childhood hearing loss after NHS that utilised methods to accurately differentiate between permanent and temporary hearing loss. Rigorous research is needed on the prevalence of permanent childhood hearing loss to inform strategies for monitoring, identification, intervention, and management.

The association of bisphenol A and paraben exposure with sensorineural hearing loss in children

Bisphenol A (BPA) and parabens (PBs) are chemicals that are extensively used in personal care products (PCPs). In early childhood development, hearing is critical to speech and language development, communication, and learning. In vitro and in vivo, BPA/PBs exhibited neurotoxicity through elevated levels of oxidative stress. BPA also has the potential to be an ototoxicant. Therefore, this study aimed to determine the association of exposure to BPA/PBs with sensorineural hearing loss in children. A cross-sectional study based on hearing tests was conducted. This study enrolled 320 children aged 6-12 years from elementary school. Urinary BPA and PB concentrations were analyzed by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Logistic regression models were employed to determine the association of BPA/PB exposure with sensorineural hearing loss. Children with sensorineural hearing loss had higher BPA concentrations than normal-hearing children (0.22 ng/ml vs. 0.10 ng/ml, p = 0.05). After adjustment for covariates, the risk of hearing loss at middle frequencies reached 1.83-fold (95% CI: 1.12-2.99) when BPA concentrations increased by 1 log10. The risk of slight hearing loss reached 2.24-fold (95% CI: 1.05-4.78) when children had a tenfold increase in ethyl paraben (EP) concentration. This study clarifies the role of exposure to BPA/PBs in hearing loss in children. Future research needs to be expanded to include cohort designs and nationwide studies to identify causality.

Assessment of the Hearing Status of School-Age Children from Rural and Urban Areas of Mid-Eastern Poland

(1) Background: The purpose of this study was to assess the prevalence of hearing loss in school-age children from rural and urban areas of mid-eastern Poland using standard audiological tests-pure tone audiometry (PTA), impedance audiometry (IA), and otoacoustic emissions (OAEs). (2) Methods: Data were collected from a group of 250 children aged 8 to 13, made up of 122 children from urban areas and 128 children from rural areas of mid-eastern Poland. Hearing was assessed in each of the subjects by means of PTA, IA (tympanometry), and transient-evoked OAEs (TEOAEs). Otoscopy was also performed. (3) Results: There were significantly fewer abnormal results in children from urban than rural areas: they were, respectively, 10.1% and 23.1% for IA, 3% and 9.7% for PTA, and 17.3% and 31.8% for TEOAEs. For hearing-impaired ears in rural areas (failed TEOAE), hearing thresholds were, on average, 11.5 dB higher at 0.5 kHz than for children in urban areas. Comparison of each PTA result with the corresponding IA showed that all cases of hearing loss were related to malfunction of the middle ear. (4) Conclusions: The results of all three hearing tests were significantly worse in children from rural areas compared to those from urban areas. This indicates that audiological healthcare in rural areas needs improvement and that universal hearing screening programs for school-age children would be helpful.

Prevalence of extended high-frequency hearing loss among adolescents from two rural areas in Colombia

OBJECTIVE

Worldwide research trends on the prevalence of hearing loss within young rural populations are scarce. Current evidence suggests extended high-frequency audiometry could be a sensitive predictor to detect subclinical hearing loss. This study aimed to determine the prevalence of hearing loss through conventional pure tone (0.25-8 kHz) and extended high-frequency (9-20 kHz) audiometry tests in a group of adolescents aged 13 to 19 years old from two rural areas of Colombia. A sociodemographic and associated factor for hearing loss questionnaire was applied.

DESIGN

Cross-sectional study.

STUDY SAMPLE

Three hundred sixty-six adolescents aged 13 to 19 years old from two rural municipalities in Colombia: Soracá, and Palmas del Socorro.

RESULTS

Hearing loss prevalence assessed through pure tone audiometry was 3.28% in right ears and 3.83% in left ears while through extended high-frequency audiometry was 14.21% and 13.11%, respectively. Associated factors found by the logistic regression were age (OR: 1.36; CI 95% 1.13-1.64) and obesity (OR: 3.74; CI 95% 1.07-13.11).

CONCLUSIONS

Using 15 dB as the normal hearing threshold parameter for audiometric frequencies, our results suggest that extended high-frequency hearing loss is already widespread among rural adolescents. This highlights the need for research on extended high-frequency audiometry in rural school-aged children.

Sex and rural-urban differences in the prevalence of childhood visual impairment in Taiwan: A nationwide population-based study

BACKGROUND

Visual impairment (VI) is a major developmental disability in children, but data at the national level are limited.

AIMS

We conducted a nationwide study in Taiwan to assess the sex and rural-urban differences in VI.

METHODS AND PROCEDURES

Using data from the national disability registry, we calculated prevalence rates by age, sex, and geographic area and assessed changes from 2004 to 2010. We excluded cases under 3 years old because the government discourages certification at this age.

OUTCOMES AND RESULTS

Between 2004 and 2010, the overall prevalence rate fluctuated between 3.48/10,000 and 3.66/10,000. Boys had higher prevalence rates in all years, and the boy-to-girl prevalence rate ratios ranged from 1.24 to 1.30 (p < 0.05 in all years), without an apparent time trend. The rates generally decreased over time in rural areas (p=0.008), but increased in urban areas (p=0.029); this resulted in a decreasing time trend (p = 0.001) in the rural-to-urban prevalence rate ratios (1.32 to 1.09; p < 0.05 except for 2010).

CONCLUSIONS AND IMPLICATIONS

Boys are more likely to experience VI in Taiwan. Rural areas had higher prevalence rates than urban areas, but the difference has been decreasing over time. Identifying factors underlying this reduction may help the prevention of VI.