Hearing loss in children with very low birth weight: current review of epidemiology and pathophysiology

Abstract

An association between birth weight <1500 g (very low birth weight (VLBW)) and hearing loss has been long recognised. As universal hearing screening programmes have become widely implemented and the survival rate of VLBW babies in modern intensive care units has increased, we have gained a substantially better understanding of the nature of this problem. However, many gaps in our knowledge base exist. This review describes recent data on hearing loss in the VLBW population and explains the current level of understanding about the physiological basis underlying the auditory deficits in these patients. Although VLBW alone may not have a severe impact on hearing, it is commonly associated with multiple other risk factors that can alter hearing in a synergistic fashion. Therefore, the risk of hearing loss is substantially higher than in the general newborn population. Also, it is important to perform a more comprehensive audiometric evaluation than standard otoacoustic emission screening for infants who are in the neonatal intensive care unit in order not to miss hearing loss due to retrocochlear pathology. Furthermore, children with VLBW are also at increased risk of experiencing progressive or delayed-onset hearing loss, and thus should continue to have serial hearing evaluations after discharge from the neonatal intensive care unit.

Selective Inner Hair Cell Loss in Prematurity: A Temporal Bone Study of Infants from a Neonatal Intensive Care Unit

“…Prevalence increases to 3% if the sample is limited to premature infants born G28 weeks' gestation (Robertson et al 2009). Many risk factors have been suggested, including low birth weight, respiratory distress, hyperbilirubinemia, acoustic injury, and ototoxic drugs (Cristobal and Oghalai 2008;Teagle et al 2010). However, little is known about the underlying cochlear histopathology because biopsy of the human inner ear is impossible, and there are relatively few descriptions of temporal bone histopathology in neonatal ears (Slack et al 1986;Amatuzzi et al 2001).…”

Risk Factors for Congenital Hearing Loss: Which Are the Most Relevant?

“…19,20 Neonates admitted to the neonatal intensive care unit had a PASS rate of 82.4%, while those who were not admitted there had a PASS rate of 91.6%, the difference proving to be statistically significant (p = 0.048). Neonates requiring mechanical ventilation had a PASS rate of 71.7%, while for those without the need for mechanical ventilation the PASS rate was 91.5%, the difference proving to be statistically significant (p <0.001).…”

Incidence and Impact of CMV Infection in Very Low Birth Weight Infants

“…In preterm VLBW infants without CMV, estimates of the incidence of hearing loss range from 0.7% to 2%. 17,22 In term infants with congenital CMV, it is estimated that 17% to 20% of infants will have hearing loss or neurodevelopmental impairment. 23 In the current study, we found that CMV-positive VLBW infants had significantly higher rates of SNHL (83% vs 2%), abnormal neuroimaging (72% vs 25%), and poor motor outcomes (43% vs 9%) when compared with CMVnegative VLBW controls.…”