IMPORTANCE Pediatric single-sided deafness (SSD) can seriously affect development, causing impaired spatial hearing skills, speech-language delays, and academic underachievement. Early cochlear implantation likely improves hearing-related outcomes, but its association with language development remains unclear.OBJECTIVE To investigate whether early cochlear implantation is associated with language outcomes for children with prelingual SSD.
DESIGN, SETTING, AND PARTICIPANTSThe Cochlear Implant for Children and One Deaf Ear study was initiated in 2015 and recruited participants at 4 academic hospitals in Flanders, Belgium, through 2019. This cohort study included 3 groups of children aged 2 to 5 years: children with SSD and a cochlear implant, children with SSD without a cochlear implant, and a control group with normal hearing. Language and hearing skills were assessed 1 to 2 times per year until the age of 10 years.Study completion rates were high (82%). Data analysis was performed from October to December 2020. EXPOSURE Unilateral cochlear implant.
MAIN OUTCOMES AND MEASURESLongitudinal vocabulary, grammar, and receptive language scores. The implanted group was hypothesized to outperform the nonimplanted group on all language tests. RESULTS During the recruitment period, 47 children with prelingual SSD without additional disabilities were identified at the participating hospitals. Fifteen of the 34 children with an intact auditory nerve received a cochlear implant (44%, convenience sample). Sixteen of the remaining children were enrolled in the SSD control group (50%). Data from 61 children (mean [SD] age at the time of enrollment, 2.08 [1.34] years; 26 girls [42%]) were included in the analysis: 15 children with SSD and a cochlear implant, 16 children with SSD without a cochlear implant, and 30 children with normal hearing. Children with SSD and a cochlear implant performed in line with their peers with normal hearing with regard to grammar. In contrast, children with SSD without a cochlear implant had worse grammar scores than the group with implants (−0.76; 95% CI, −0.31 to −1.21; P = .004) and the group with normal hearing (−0.53; 95% CI, −0.91 to −0.15; P = .02). The 3 groups had similar vocabulary and receptive language abilities. CONCLUSIONS AND RELEVANCE These findings suggest that early cochlear implantation is associated with normal grammar development in young children with prelingual SSD. Although further follow-up will reveal the long-term outcomes of the cochlear implant for other skills, the (continued) Key Points Question Is early cochlear implantation associated with language development in children with prelingual single-sided deafness (SSD)? Findings In this longitudinal cohort study of 61 children, children with SSD with a cochlear implant achieved significantly better scores for grammar than children with SSD without an implant (difference in score, 0.76), similar to scores for children with bilateral normal hearing. Vocabulary and receptive language scores did not differ for the 3 groups. Me...