Assessment of sensory impairment in older adults with dementia

Background: Over 55 million people worldwide are living with dementia. The rate of cognitive decline increases with age, and loss of senses may be a contributing factor. Objectives: This study aimed to analyze hearing, olfactory function, and color vision in patients with dementia. Materials and methods: The sample comprised 40 patients with dementia and 37 cognitively normal controls aged 41–85 years. All participants underwent conventional pure-tone audiometry and a screening version of the Hearing Handicap Inventory for Adults, the Odorized Markers Test of olfactory function and the Ishihara color vision test. The effects of comorbidities and lifestyle factors were also assessed. Results: Patients with dementia had significantly worse hearing at almost all frequencies tested and significantly greater olfactory impairment than cognitively normal controls. Color vision impairment was found in less than 8% of the sample, with no significant difference between the groups. Impairment of two senses (hearing and olfaction) was significantly more common in patients with dementia than in controls. Conclusion: Individuals with dementia were found to have sensory decline, namely hearing and olfactory impairment. Color vision was rarely impaired in the sample. Participants with dementia tended to have more multisensory impairments than controls.