Download 1) Department of Otolaryngology, Massachusetts Eye and Ear

Differential Cochlear Implant Outcomes in Older Adults
Daniel S.
1,2
Roberts ,
MD/PhD, Harrison W.
1,2
Lin ,
MD, Barbara S.
2,3
Herrmann ,
PhD and Daniel J.
1,2
Lee ,
MD
1) Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA.
2) Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02114, USA.
3) Department of Audiology, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA.
ABSTRACT
RESULTS
RESULTS
Table 1. Patient Demographics.
Objective/Hypothesis: The goals of this study were to 1) analyze whether cochlear implant
(CI) users over 65 years of age have different surgical and audiological outcomes when
compared to younger adult CI users and 2) identify reasons for these possible differences.
Study Design: Retrospective single institution study
Methods: Records of 113 post-lingually deafened adults with unilateral cochlear implants were
reviewed. Preoperative and postoperative speech perception scores, medical and epidemiological
data were recorded and analyzed.
Results: Speech perception ability was significantly poorer in CI users over 65 years of age
compared to younger adult patients (p=0.012). Patients over the age of 80 accounted for these
findings (p=0.017). Older patients were less likely to have a family history of hearing deficits. A
history of noise exposure and idiopathic cause of hearing loss had no impact on audiological
outcomes. A family history of hearing loss was associated with a trend towards better speech
recognition (p=0.062). Older patients did not experience more vestibular symptoms or other
complications compared to younger patients.
Conclusions: Patients over the age of 80 had lower speech perception scores than other adult
CI recipients but did not have higher rates of dizziness or vertigo after surgery. A family history
of hearing loss was associated with a trend towards better speech recognition possibly
representing a new prognostic variable. These findings provide important information that will
aid clinicians in counseling older CI candidates.
P value
Group
N
Average Age
Female
Audiological Follow-up (months)
Duration Hearing Loss (months)
Noise exposure
Family History of Hearing Loss
Etiology Idiopathic
History of Neurological Disease
Device/Electrode
AB HiRes 90K/HiFocus Helix
AB HiRes 90K/HiFocus 1j
Cochlear Freedom Contour
Cochlear Freedom Advance
Nucleus CI512/Contour Advance
>65
67
75.5 +/- 0.9
30 (44.7%)
13.7+/- 1.4
290.7 +/- 25.2
15 (22.4%)
18 (26.9%)
31 (46.2%)
3 (4.5%)
<65
46
49.5 +/- 1.5
21 (45.6%)
13.2 +/- 1.5
224.8 +/- 24.4
6 (13.0%)
22 (47.8%)
14 (30.4%)
4 (8.7%)
1.000
0.802
0.068
0.231
0.028*
0.118
0.440
18 (26.9%)
29 (43.3%)
1 (1.5%)
3 (4.5%)
11 (16.4%)
10 (21.7%)
21 (45.6%)
2 (4.3%)
5 (10.9%)
13 (28.3%)
0.650
0.849
1.000
0.267
0.162
* =statistically different groups. Average age, Audiological Follow-up, and Duration of Hearing
Loss are +/- SEM. AB=Advance Bionic. History of neurological disease was defined as a history
of a CNS malignancy, stroke, head injury, or degenerative neurological disorder.
Table 2. Analysis of factors contributing to postoperative CNC scores.
INTRODUCTION
Older adults constitute a rapidly growing demographic group in the United States. The number
of adults over the age of 65 is expected to double between the years 2000 and 2030, with 72
million Americans representing 20% of the population by 2030 (1). The interest and demand for
cochlear implant (CI) surgery among older adults with severe to profound hearing loss will likely
increase accordingly.
CNC score
Age > 65years
Noise exposure
Family History of Hearing Loss
Etiology Idiopathic
Duration Hearing Loss (months)
Advanced age is not considered a contraindication to CI candidacy. Several studies have shown
that older adults do benefit from CI, with improvements both in hearing abilities and quality of
life (2,3,4,5). However, current studies are conflicting as to whether elderly patients have similar
audiological and surgical outcomes as compared to younger adult patients. The most recent data
suggest that elderly patients benefit from cochlear implantation but have lower mean speech
recognition scores compared to adult patients under the age of 65 (6). These two patient groups
were matched for speech perception and duration of deafness preoperatively. These data are in
contrast to other reports showing similar audiological outcomes between younger and older adult
CI users (3,4,5).
To resolve these conflicting findings in the literature we performed a retrospective review of
post-lingually deafened adults with unilateral cochlear implants implanted at our institution to
study the influence of advanced age. We stratified our cohort to determine whether a subgroup
of CI users over 65 years of age might demonstrate lower word intelligibility scores (consonantnucleus-consonant or CNC) compared to younger adult patients. We also analyzed the effects of
duration of hearing loss, history of noise exposure, and family history of hearing loss on CI
performance.
Yes
52.36 +/- 2.67
56.04 +/- 2.42
63.19 +/- 3.27
55.62 +/- 3.93
No
63.21 +/- 3.37
60.20 +/- 4.57
53.66 +/- 2.71
57.48 +/- 2.51
Coefficient
-9.09 +/- 4.48
2.01 +/- 5.77
8.74 +/- 4.65
-0.63 +/- 4.43
-0.02 +/- 0.01
P value
Univariate Multivariate
0.012*
0.041*
0.463
0.729
0.037*
0.062
0.676
0.887
0.114
* =statistically different groups. Data are average +/- SEM.
Table 3. Surgical Complications
Figure 1. Cochlear implant outcomes in patients over 65 years. 67 patients were over 65 years and
46 were below 65 years of age. Mean pre-operative and post-operative CNC are shown. Values are
reported as mean scores +/- SEM. *p=9.23 E-22; **p=6.33 E-22; ***p=0.0124.
METHODS
Group
N
Post-op Dizziness/Vertigo
Implant failure
Perilymphatic fistula
Infection (device removed)
Wound complication
Delayed facial nerve paresis
Permanent facial nerve injury
Post-op delirium
TOTAL:
>65
67
10 (14.9%)
1
1
0
2
2
0
1
17 (25.3%)
<65
46
8 (17.3%)
1
0
1
0
0
0
0
10 (21.7%)
P value
1.00
0.822
DISCUSSION
This study was approved by the Human Studies Committee of the Massachusetts Eye and Ear
Infirmary (09-07-065X). We performed a retrospective review of CI patients at our institution
over the period 2006 to 2010. Patients were included in our analysis if they were 1) postlingually deafened, 2) 18 years of age or older, 3) underwent a single cochlear implant and 4)
had follow-up audiologic data after at least 5 months CI use. Demographic and medical data
were analyzed. Audiologic data recorded included CNC scores before and after implantation.
While elderly implant patients are more likely to have poorer speech perception when compared to
younger adult recipients, they still demonstrate significant hearing gains following CI surgery. Our results
furthermore suggest that better speech perception may be associated with a family history of hearing loss.
Importantly, we show that while vertigo/disequilibrium is a common finding among all cochlear implant
recipients, older patients are at no greater risk of experiencing these symptoms. These observations
provide useful guidance for clinicians counseling older patients considering cochlear implantation
surgery.
Speech Testing: Preoperatively, the CNC test was performed using headphones (TDH-49) at a
level that was predicted to be the maximum speech perception score. Postoperatively, CNC
testing was done in the soundfield with the patient using the CI alone and facing the speaker
(0o azimuth) using a presentation level of 65 dB HL. If the patient had better hearing in the
contralateral ear or wore a hearing aid in that ear, the contralateral ear was plugged or the
hearing aid turned off during the testing. The maximal CNC score obtained after at least 5
months of implant experience was used.
Data Analysis: Multivariate regression analysis was performed using STATA software to analyze
differences in mean CNC score between age groups. Univariate analysis was performed using
an unpaired t-test. Chi square analysis and Fisher’s exact test were used to test for any
differences in categorical data including the frequency of post-operative complications.
Analysis of variance (ANOVA) and Bonferroni post-test was utilized to determine differences
between CNC performance based on decade of life.
Figure 2: Cochlear implant outcomes by decades. Patients in the 20-30s (N=7), 40s (N=19), 50s
(N=14), 60s (N=26), 70s (N=25), and 80s (N=22) were compared. *p=0.019; #p=0.09.
REFERENCES
1) He W, Sengupta M, Velkoff VA, et al. 65 in the United States. Washington, DC: US Census Bureau; 2005. Quality-of-life benefit from cochlear implantation
in the elderly.
2) Vermeire K, Brokx JP, Wuyts FL, Cochet E, Hofkens A, Van de Heyning PH. Quality-of-life benefit from cochlear implantation in the elderly. Otol Neurotol
2005 26(2):188-95.
3) Djalilian HR, King TA, Smith SL, et al. Cochlear implantation in the elderly: results and quality-of-life assessment. Ann Otol Rhinol Laryngol 2002;111:890895.
4) Labadie RF, Carrasco VN, Gilmer CH, et al. Cochlear implant performance in senior citizens. Otolaryngol Head Neck Surg 2000;123(4):419-24.
5) Pasanisi E, Bacciu A, Vincenti V, et al. Speech recognition in elderly cochlear implant recipients. Clin Otolaryngol 2003;28:154-157.
6) Friedland, DR, Runge-Samuelson, C., Baig, H, et al. Case-Control Analysis of Cochlear Implant Performance in Elderly Patients. Arch Otolaryngol Head
Neck Surg 2010; 136(5):432-8.
Figure 2: Cochlear implant outcomes by age. Postoperative CNC scores are shown by age at implantation.
Outcomes of octagenarians are highlighted by shading.
ACKNOWLEDGEMENTS
We would like to thank Dr. Joseph B. Nadol for his thoughtful comments and his review of this manuscript. We would also
like to thank the Massachusetts General Hospital Biostatics Center for assistance with statistical analysis.