Performance of Older Adult Cochlear Implant Users in Hong Kong

Objective: To compare the speech perception performance of older adults with that of adult cochlear implant (CI) recipients in a single center in Hong Kong. Design: A retrospective study of 14 older adult CI users (age at operation, 56 to 77 yr old) and 14 adults (age at operation, 18 to 53 yr old) who received CIs and were matched for duration of profound deafness. The outcome indicator of their performance includes ratings of 0 to 7 on the speech perception category (SPC), which is based on their speech perception test scores at 6, 12, and 24 mo after implantation. Statistical analyses were used to compare SPC ratings between the two groups at the tested intervals. Results of specific speech perception tests between the two groups were also analyzed at the tested intervals, along with the rate of improvement of the specific tasks from 0 to 6 mo, 0 to 12 mo, and 0 to 24 mo postoperatively. Multiple regression analysis was used to assess which variables would independently predict the outcome performance of CIs. Results: There were no significant differences (p = 0.228 to 0.724) between the SPC ratings of the adult group and the older adult group at the tested intervals. The adult group scored significantly better in the postoperative 0- to 6-mo improvement rate (p = 0.047) in open-set sentence recognition, but the improvement decelerated so that it was comparable with that of the older adult group by 12 mo after implantation. The adult group also scored significantly better (p = 0.031) in tone identification at 24 mo after implantation compared with the older adult group. The majority of the speech perception task scores, and rates of improvement were comparable between the older adult group and the adult group at the tested time intervals. Multiple regression analysis revealed a significant relationship (p = 0.025) between the outcome indicator of everyday sentence recognition at 12 mo after implantation and the outcome predictor of duration of profound deafness. However, the goodness of fit (r2) of this model was 0.11, suggesting that only 11% of the variance in 12-mo postoperative everyday sentence recognition was explained by duration of profound deafness, leaving a large proportion of unexplained variance. Conclusion: The overall performance of the older adult CI recipients is comparable with that of the adult group. Duration of profound deafness, irrespective of age, is accountable for a small part of the outcome. Because older adults as well as younger adults can benefit from CIs, age should not be the predominant factor for declining CIs among older adults.