Hearing loss is a modifiable risk factor for dementia in older adults. Whether hearing aid use can delay the onset of cognitive decline is unknown. Participants in this study (aged 62–82 years) were assessed before and 18 months after hearing aid fitting on hearing, cognitive function, speech perception, quality of life, physical activity, loneliness, isolation, mood, and medical health. At baseline, multiple linear regression showed hearing loss and age predicted significantly poorer executive function performance, while tertiary education predicted significantly higher executive function and visual learning performance. At 18 months after hearing aid fitting, speech perception in quiet, self-reported listening disability and quality of life had significantly improved. Group mean scores across the cognitive test battery showed no significant decline, and executive function significantly improved. Reliable Change Index scores also showed either clinically significant improvement or stability in executive function for 97.3% of participants, and for females for working memory, visual attention and visual learning. Relative stability and clinically and statistically significant improvement in cognition were seen in this participant group after 18 months of hearing aid use, suggesting that treatment of hearing loss with hearing aids may delay cognitive decline. Given the small sample size, further follow up is required.

Objectives: Hearing loss is highly prevalent in older adults and is independently associated with accelerated cognitive decline. Cochlear implants are usually the only effective treatment for people with severe–profound hearing loss, who have the highest risk of cognitive decline and dementia, however, very few receive them. Current evidence of the effects of cochlear implant use on cognitive decline/dementia outcomes is limited and unclear. This study aimed to investigate the effect of cochlear implant use on longitudinal cognitive performance, as this intervention may be an effective method of modifying cognitive outcomes for older adults with significant hearing loss. Methods: This prospective longitudinal observational study investigated cognitive performance in a convenience sample of older adults (mean age 74 years) with cochlear implants over 4.5 years post-implantation, comparing this with that of community-living adults with untreated hearing loss/normal hearing over 3 years (Australian Imaging, Biomarker and Lifestyle Flagship Study of Ageing; AIBL). All participants were assessed at 18-month intervals from baseline using the same measures. Panel regression was used to compare cognitive trajectories. Results: Cochlear implant users demonstrated significantly improved performance in executive function and working memory, as well as stability in attention, psychomotor function, and visual learning at 4.5-year follow-up. Comparatively, AIBL participants showed significantly greater worsening performance per year in attention and psychomotor function, and stability in working memory and visual learning at 3-year follow-up. Conclusions: Cochlear implant use may delay cognitive decline and/or improve cognitive performance in older adults with severe–profound hearing loss, providing proof-of-concept evidence of the positive effects of hearing intervention on cognitive performance in older adults with hearing loss.