The impact of ethnicity on cochlear implantation in Norwegian children

To explore the impact of parental ethnicity on cochlear implantation in children in Norway with regard to incidence rates of cochlear implants (CIs), comorbidies, age at onset of profound deafness (AOD), age at first implantation, uni- or bilateral CI, and speech recognition.

This retrospective cohort study included all children (N = 278) aged <18 years in Norway who received their first CI during the years 2004-2010.

86 children (30.9%) in our study sample had parents of non-Nordic ethnicity, of whom 46 were born in Nordic countries with two non-Nordic parents. Compared with the background population, children with non-Nordic parents were 1.9 times more likely to have received CI than Nordic children (i.e., born in Nordic countries with Nordic parents). When looking at AOD, uni-vs. bilateral CIs, and comorbidities, no significant differences were found between Nordic children and children with a non-Nordic ethnicity. Among children with AOD <1 year (n = 153), those born in non-Nordic countries with two non-Nordic parents (n = 6) and adopted non-Nordic children (n = 6) received their first CI on average 14.9 and 21.1 months later than Nordic children (n = 104), respectively (p = 0.006 and 0.005). Among children with AOD <1 year, those born in Nordic countries with two non-Nordic parents (n = 31) received their CI at an older age than Nordic children, but this difference was not significant after adjusting for calendar year of implantation and excluding comorbidity as a potential cause of delayed implantation. The mean age at implantation for children with AOD <1 year dropped 2.3 months/year over the study period. The mean monosyllable speech recognition score was 84.7% for Nordic children and 76.3% for children born in Norway with two non-Nordic parents (p = 0.002).

The incidence of CI was significantly higher in children with a non-Nordic vs. a Nordic ethnicity, reflecting a higher incidence of profound deafness. Children born in Norway have equal access to CIs regardless of their ethnicity, but despite being born and receiving care in Norway, prelingually deaf children with non-Nordic parents are at risk of receiving CI later than Nordic children. Moreover, prelingually deaf children who arrive in Norway at an older age may be at risk for a worse prognosis after receiving a CI due to lack of auditory stimulation in early childhood, which is critical for language development and late implantation; this is a serious issue with regard to deafness among refugees.