Cognitive Outcomes After Cochlear Implantation in Older Adults: A Narrative Review of Current Evidence, Mechanisms, and Long-Term Perspectives

Background: Hearing loss is highly prevalent among older adults and represents a growing public health burden. Increasing attention has been given to the associations between hearing loss, cognitive decline, and dementia risk. Cochlear implantation is an established intervention for adults with severe-to-profound sensorineural hearing loss who obtain limited benefit from conventional amplification, but its potential cognitive effects remain debated. Objective: This narrative review summarizes current evidence on cognitive outcomes after cochlear implantation in adults and older adults, with particular attention to cognitive domains, long-term trajectories, methodological limitations, and clinical implications. Main findings: Available evidence suggests that cochlear implantation may be associated with improvement or stabilization of selected cognitive domains, particularly attention, executive function, working memory, and memory. However, findings are heterogeneous across studies, cognitive tools, and follow-up durations. Prospective longitudinal studies using hearing-adapted or visually presented cognitive batteries support the possibility of postoperative cognitive benefit, but the magnitude and durability of this effect vary between individuals and domains. Long-term studies suggest that cognitive improvement may be strongest during the first postoperative years and may later stabilize or attenuate, whereas auditory and quality-of-life benefits appear more consistently sustained. Conclusions: Cochlear implantation should be regarded as an established hearing rehabilitation strategy with robust benefits for auditory performance and quality of life, and as a potentially cognition-supportive intervention in selected older adults with severe-to-profound hearing loss. Current evidence does not yet prove that cochlear implantation prevents dementia. Future studies should use standardized hearing-adapted cognitive protocols, longer follow-up, adequate comparison groups, and clinically meaningful cognitive endpoints.