Charles Bonnet syndrome in older adults with age-related macular degeneration: Its relationship to depression and mild cognitive impairment

Abstract

Older adults are prone to have multiple chronic health conditions. The purpose of this study was to investigate whether older adults with age-related macular degeneration (AMD) who experience Charles Bonnet syndrome (CBS) are at a higher risk of developing depression and mild cognitive impairment (MCI). A total of 42 participants (31 females, 11 males; age: 68–99 years, M = 85.5 years; visual acuity [VA] in the better eye ranging from 20/70 to 20/1200) diagnosed with AMD were recruited in a vision rehabilitation center. They completed the Montreal Cognitive Assessment (MoCA) in its blind version, the Geriatric Depression Scale, and responded to questions designed to determine whether they experienced visual hallucinations consistent with CBS. Participants were then categorized into whether or not they experienced CBS, were at risk of depression or were at risk of MCI. Participants in the group experiencing CBS did not statistically show a higher likelihood of developing depression and/or MCI than those without CBS. Overall, the risk of depression (30%) was consistent with previous studies. In our sample of 42 older adults with visual impairment, 62% failed the MoCA suggesting they were at risk of cognitive decline. Our study was not able to replicate previous reports of a possible relationship between CBS and MCI in older adults with AMD; however, the observed level of possible cognitive impairment warrants further investigation. Future studies should include participants with other ocular pathologies to investigate whether a relationship among CBS, MCI, and/or depression may exist independently of AMD.