Predictive Value of GJB2 Mutation Status for Hearing Outcomes of Pediatric Cochlear Implantation

Objective To systematically review and quantify current evidence regarding the association of GJB2 mutation status with outcomes of pediatric cochlear implantation. Data Sources PubMed, Embase, and the Cochrane Library were searched for "GJB2,""pediatric hearing loss," and "cochlear implantation" and their synonyms, with no language restrictions, until December 2, 2015. Review Methods Studies were included that investigated the status of GJB2 mutation and its predictive value for outcomes of pediatric cochlear implantation. Speech recognition scores, Infant-Toddler Meaningful Auditory Integration Scale, Speech Intelligibility Rating, and Categorized Auditory Performance were pooled using weighted mean differences, and a 95% confidence interval. Results Eighteen studies met the inclusion criteria. The differences between GJB2-related deafness and non- GJB2-related deafness due to unidentified causes and other types of genetic deafness without additional disabilities were not statistically significant ( P = .15 and P = .30, respectively); however, the difference between GJB2-related deafness and acquired hearing loss due to environmental etiologies was statistically significant and favored GJB2-related deafness ( P = .03). Conclusion GJB2-related deafness leads to significantly better cochlear implantation outcomes when compared with acquired deafness caused by environmental etiologies. However, GJB2 mutation is not associated with a significantly better prognosis when compared with those whose deafness results from either nonsyndromic hearing loss of unknown origin or other types of genetic mutations in the absence of other neurologic deficits.