Prevalence of risk factors for sensorineural hearing loss in NICU newborns

The aim of this study was to determine the prevalence and significance of traditional risk factors associated with sensorineural hearing loss (SNHL) in a population of 615 neonates who attended the neonatal intensive care unit (NICU) of the University Hospital in Leuven, Belgium between January 2005 and December 2007.

Auditory brainstem response (ABR) audiometry using 40 dB stimuli was performed in all 615 neonates. A retrospective medical database analysis was performed to evaluate the influence of 14 predetermined risk factors. The evaluated risk factors were ototoxic medication, hyperbilirubinemia, in utero infections (including CMV, rubella, syphilis, herpes, and toxoplasmosis), craniofacial anomalies, syndromes associated with SNHL, low birth weight (< 1,500 g), low Apgar score, mechanical ventilation lasting for 5 days or longer, bacterial meningitis, family history of hereditary childhood SNHL, endocranial hemorrhage, hypoxic ischemic encephalopathy, convulsions, and sepsis

Uni- or bilateral hearing impairment was diagnosed in 25 out of 615 neonates (4.1%). In utero infections (especially CMV), craniofacial anomalies, and syndromes known to include SNHL were significant risk factors. For the remaining risk factors, no significant correlation with SNHL was found.

In this study, only in utero infections (especially CMV), craniofacial anomalies, and syndromes known to include SNHL were significant risk factors associated with SNHL. Adequate management of hyperbilirubinemia and ototoxic drug administration may eliminate some of the major historical risk factors associated with SNHL in NICU neonates.