Cochlear implantation in the elderly: surgical and hearing outcomes

Abstract

Background: At the present time, 50 to 60% of the population above 70 years of age suffers from a hearing impairment and from 0.6 to 1.1% has a severe to profound loss, which cannot benefit from an hearing aid. Moreover, it is expected that this prevalence will grow by more than two-fold in the next 40 years. There is strong evidence that hearing loss in older adults is associated with both cognitive load and social isolation, which in turn, are associated with cognitive and physical functioning. Cochlear implant (CI) dramatically improves sound audibility and speech understanding. The aim of this paper was to analyze outcome and complications of CI treatment in elderly patients.

Methods: A retrospective study on 17 patients, aged at implantation between 65 and 79 years (mean = 70.47 ± 3.94), unilaterally implanted for severe to profound bilateral hearing loss. The following data were statistically evaluated: pre-implant pure-tone threshold and tests of speech recognition, both with hearing aid that without; post-implant threshold and speech perception with CI off and on. Moreover, statistical correlations of PTA improvement between two age groups (65 to 70 and over 70 years) were carried out.

Results: Mean PTA improved from 111.25 (± 17.51) (pre-implant) to 43.81 (± 9.27) (post-implant); and the mean SRT improved from 90 dB to 65 dB. Moreover there was no statistical difference in PTA improvement between the two age groups (65 to 70 and over 70 years). No severe per- or post-operative surgical complications were noted.

Discussion: In the elderly, CI is a safe procedure that significantly improves hearing threshold (p < 0.00001) and speech perception (p < 0.01). Support of family and professionals, as well as duration of deafness and pre-implant scores greatly influence the results of rehabilitation and its perceived benefit. CI should not be denied in older individuals who are otherwise in good health.

Figure 1

Conceptual model of the association of hearing loss with cognitive and physical functioning in older adults (from F. Lin, 2012)[3]

Figure 2

External and internal parts of a cochlear implant

Figure 3

Pre- and post-operative PTA (P1=pre-op, side implanted; P2=pre-op, free field without hearing aids; P3=pre-op, free field with hearing aids; A=post-op at activation; C1=post-op, 1st control; C2=post-op, 2nd control; C3=post-op, 3rd control; C4=post-op, 4th control; C5=post-op, 5th control)

Figure 4

Pre- and post-implant mean speech detection threshold (SDT) and mean speech recognition threshold (SRT) (P2=pre-op, free field without hearing aids; P3=pre-op, free field with hearing aids; C1=post-op, 1st control; C2=post-op, 2nd control; C3=post-op, 3rd control; C4=post-op, 4th control; C5=post-op, 5th control)