Universal newborn hearing screening and postnatal hearing loss.
OBJECTIVE
The goal of this study was to determine the percentage of children who have a postnatal permanent childhood hearing impairment (PCHI) and the percentage thereof who have risk indicators for a postnatal hearing loss.


METHODS
Data were drawn retrospectively from the clinical charts of children who had bilateral PCHI (>40 dB hearing level, better ear, unaided) and had undergone universal newborn hearing screening (UNHS) between 1995 and 2000 in various Austrian hospitals. A hearing loss was recognized as postnatal when a child passed UNHS but was later found to have a hearing impairment. The presence of risk indicators, as suggested by the Year 2000 Statement of the American Joint Committee on Infant Hearing (JCIH), was assessed by reviewing the children's clinical charts.


RESULTS
Of a total of 105 children with bilateral PCHI, 23 (22%) showed postnatal impairment. After correction of this number for underascertainment, postnatal impairment was estimated to account for 25% of all bilateral PCHI at age 9 years. Risk indicators were found in 17 children but did not fully correspond to those proposed by the JCIH. The risk factors found were a family history of hearing loss (3 children), meningitis (2), craniofacial malformation (2), persistent pulmonary hypertension (1), congenital cytomegaly infection (1), extracorporeal membrane oxygenation (1), recurrent otitis media with effusion (1), and, in addition to the JCIH list, ototoxic therapy (5), and birth before 33rd gestational week (2) (1 child had a combination of the last 2). Six children showed no risk indicators for the postnatal hearing loss.


CONCLUSIONS
Our findings suggest that approximately 25% of bilateral childhood hearing loss is postnatal, which supports the leading role of UNHS in detecting PCHI. Provisions for also identifying postnatal cases nevertheless are justified. Because in some of these children no risk indicators are detectable and in others the hearing deterioration starts after age 3 years, audiologic monitoring of at-risk children up to this age may not be sufficient. Additional methods, such as hearing screening at nursery schools or schools, are recommended.
Weichbold
Viktor
V
Clinical Department of Hearing, Voice and Speech Disorders, Innsbruck Medical University, Innsbruck, Austria. viktor.weichbold@uklibk.ac.at
Nekahm-Heis
Doris
D
Welzl-Mueller
Kunigunde
K
D002648:Child; D005072:Evoked Potentials, Auditory; D006312:Hearing Loss, Bilateral / Q000151:congenital* / Q000175:diagnosis*; D006801:Humans; D007231:Infant, Newborn; D015997:Neonatal Screening; D017084:Otoacoustic Emissions, Spontaneous; D012189:Retrospective Studies; D012307:Risk Factors