Effect of cochlear implantation on cognitive decline and quality of life in younger and older adults with severe-to-profound hearing loss

Abstract

Purpose: (a) To measure the change in cognition, the improvement of speech perception, and the subjective benefit in people under and over 60 years following cochlear implantation. (b) To assess the relationship between cognition, demographic, audiometric, and subjective outcomes in both age groups.

Methods: 28 cochlear implant (CI) users were assigned to the < 60y group and 35 to the ≥ 60y group. Cognition was measured using the Repeatable Battery for the Assessment of Neuropsychological Status for Hearing impaired individuals (RBANS-H); subjective benefit was measured using the Nijmegen Cochlear Implant Questionnaire (NCIQ); the Glasgow Benefit Inventory (GBI); the Hearing Implant Sound Quality Index (HISQUI₁₉); Speech, Spatial and Qualities of Hearing Scale (SSQ₁₂); and the Hospital Anxiety and Depression Scale (HADS).

Results: Prior to surgery: the RBANS-H total score positively correlated with the domains "Advanced sound", "Self-esteem", and "Social functioning" of NCIQ, and negatively with HADS scores. 12 months post-implantation: the RBANS-H total score increased in the < 60y (p = 0.038) and in the ≥ 60y group (p < 0.001); speech perception and subjective outcomes also improved; RBANS-H total score positively correlated with "Self-esteem" domain in NCIQ. Age and the RBANS-H total score correlated negatively in the ≥ 60y group (p = 0.026).

Conclusions: After implantation, both age groups demonstrated improved cognition, speech perception and quality of life. Their depression scores decreased. Age was inversely associated with cognition.

Keywords: Age; Cochlear implant; Cognition; Quality of life; Speech perception.

Fig. 1

Non-modifiable and potentially modifiable risk factors of dementia across lifespan. Around 40% of cognition decline is may be explained by a mix of potentially modifiable risk factors: low educational level, hypertension, obesity, smoking, depression, physical inactivity, diabetes, low social contact, excessive alcohol consumption, air pollution, traumatic brain injury, and hearing loss. Conversely, genetics are believed to produce a 7% decrease in dementia incidence. Modified after [6, 45]

Fig. 2

Score conversion sheet with the 5 domains (I-V) and the 12 subtests (1–12)

Fig. 3

Cognitive abilities represented by the total Repeatable Battery for the Assessment of Neuropsychological Status for Hearing impaired individuals (RBANS-H) score and domain scores for the < 60y group (light grey) and the ≥ 60y group (dark grey). Higher scores indicate better cognition. The boxplots represent the minimum, 1st quartile, median, 3rd quartile, and maximum of the RBANS-H total and domain score before implantation (PreOP) and 12 months after implantation (PostOP). A Between-group comparison of the RBANS-H scores pre- and post-operatively. B Within-group comparison of the PreOP and PostOP RBANS-H scores. C Between-group comparison of the changes in the total and domain scores after implantation. *p < 0.05

Fig. 4

Preoperative (white) and postoperative (grey) Nijmegen Cochlear Implant Questionnaire (NCIQ) results in the < 60y group (A) and in the ≥ 60y group (B). *Statistically significant, p < 0.05

Fig. 5

Pre- and post-implantation total scores. A Hearing Implant Sound Quality Index (HISQUI₁₉). B Speech, Spatial and Qualities of Hearing Scale (SSQ₁₂). C Hospital Anxiety and Depression Scale (HADS). *Statistically significant, p < 0.05