Changes in Patient Characteristics of Pediatric Cochlear Implant Candidates Over a 20-Year Timeframe Affect Language Outcomes and Equity of Healthcare.

Abstract

Objectives: To determine how the patient profile of pediatric cochlear implant recipients changed over a 20-year period in an inner-city clinic (typical of many larger clinics), and to understand how these changes were influenced by clinical practice and changes in society. To relate changes in patient profile to long-term language outcomes, the primary purpose of pediatric cochlear implantation.

Design: A retrospective, observational study of children implanted between 1998 and 2019 was conducted. Longitudinal language outcomes from preimplant to 5-year postimplant were collected from all children reaching the 5-year clinical review (179 children). Demographic factors of home language, onset of severe to profound deafness (congenital, progressive, or acquired), age at implantation, device configuration (unilateral, bimodal, bilateral), and socioeconomic status were collected for the entire sample (414 children) to understand changes over time. Chi-square, Kruskal-Wallis, and Analysis of Variance tests were conducted to determine if demographic factors changed over time and Logistic Regressions were conducted to understand which factors predicted language outcomes.

Results: Over the 20-year period, we observed a significant increase in the percentage of children from non-native English-speaking families (24 to 67%), influenced by population migration. There was a significant increase in the percentage of children with progressive onset of deafness (8 to 45%), influenced by UK National Institution of Health and Care Excellence guidance which saw a relaxation in audiometric criteria such that greater numbers of children with progressive losses were eligible. Age at implantation significantly decreased due to greater surgical confidence, increased awareness of the benefits of implanting babies under 12 months and the introduction of newborn hearing screening. There was a significant reduction in the Index of Multiple Deprivation (proxy for socioeconomic status) believed to be related to recession, austerity, and population migratory trends. Regression analyses suggested that onset of deafness, age at implantation, year of implantation, income deprivation, and parental education were key predictors of 5-year post-implantation language abilities.

Conclusions: Multiple factors affect long-term speech and language outcomes in children growing up using cochlear implants. Influential factors can alter over time due to changes in clinical practice/guidance or changes in society affecting cultural/linguistic distribution. If this complex and dynamically changing landscape of influential factors is well understood, appropriate interventions can be introduced for families that are most in need of them to facilitate faster rates of language acquisition. Clinical services should be streamlined and changes in patient characteristics monitored to provide equitable treatment.