Visual Impairment Associated With Negative Effects on Older Adults With Dementia

Older adults with a diagnosis of dementia more commonly have visual impairment (VI), which is associated with negative effects in both the older adult and their caregivers, according to a review published in BMC Geriatrics.

Approximately 43.8 million older adults were living with dementia in 2016 and 173 million people were living with severe or moderate VI in 2010. Many older adults are likely to have both conditions, which could affect quality of life, as VI can increase disorientation, confusion, poor mental health, and social isolation. This review aimed to assess the prevalence of VI in adults with dementia, the impact of VI on adults living with dementia, and the effect of VI and dementia on caregivers.

Studies were included in the review if they included people with dementia and had some measure of VI or eye disease. Studies about caregivers for people with dementia and VI were also included. Any definition of VI was accepted, and studies that involved the presence of common eye diseases were included. Studies were excluded if the eye disease was a part of the dementia process rather than a separate comorbidity. They were also excluded if they had the wrong study population or had no outcome data.

The databases Ovid MEDLINE, Embase, PsycINFO, CINAHL, Scopus, Web of Science, Google Scholar, and Open Grey were used to collect studies on the subject, with the search being conducted on April 13, 2020. Type of dementia, type of VI, how dementia and VI were assessed, the type of impact, how the impact was measured, and the size of effect and prevalence were all extracted from the selected studies.

There were 37 studies included in the review, of which 34 were quantitative and 3 were qualitative; 18 studies were cross-sectional and 12 were case control studies. There were 10 studies that gave data on the effect of VI on older people living with dementia and 31 that had data on prevalence; there was only 1 study that provided information on caregivers. There were 9 studies from the United States and 10 studies from the United Kingdom.

Prevalence of glaucoma ranged from 0.2% to 26%, with prevalence higher in nursing homes. Prevalence of age-related macular degeneration (AMD) ranged from 5% to 53%. Prevalence of cataracts ranged from 0.2% to 74%. Diabetic retinopathy was reported in only 2 studies, in which the prevalence was 19% in a hospital in Singapore and 2% in a community-based study in the United Kingdom.

There were 10 studies that had data on the effect of VI in older adults with dementia. A study found that people with VI and dementia had a higher risk of inpatient admission compared with older adults with dementia who didn’t have VI or a hearing impairment (odds ratio [OR], 1.82; 95% CI, 1.17-2.82). An increased likelihood of hospice was also found in adults with VI and dementia compared with those living with dementia alone (OR, 2.11; 95% CI, 1.05-4.21). No significant difference was found in older adults with dementia who had hearing impairment only or VI only compared with those who didn’t have either. Annual health costs were not found to be significantly different.

A study found that inpatient visits were increased in adults with dementia and VI compared with those with VI alone (Cognitive Function and Ageing Study [CFAS] I: OR, 3.5; 95% CI, 1.1-11.5; CFAS II: OR, 1.7; 95% CI, 0.9-3.2). Decreased activities of daily living (ADL) were also reported in 3 studies, with less independence in ADLs associated with adults who had comorbid VI along with dementia. Adults with dementia and VI also had more activity limitations compared with adults without either (OR, 1.97; 95% CI, 1.72-2.21), which was greater than activity limitation in those with dementia alone.

Use of care workers was greater in older adults with dementia and VI in 2 samples (CFAS I: OR, 5.8; 95% CI, 1.8-19.2; CFAS II: OR, 6.4; 95% CI, 2.6-15.5). The caregivers of people with dementia and VI spent 1.7 times more hours on caregiving (95% CI, 1.4-2.2) compared with caregivers of those without either.

A scoping review was used for this research, so the quality of studies was not assessed.

The researchers concluded that VI is associated with negative effects on adults who are also living with dementia.

Reference

Zhang W, Roberts TV, Poulos CJ, Stanaway FF. Prevalence of visual impairment in older people living with dementia and its impact: a scoping review. BMC Geriatr. 2023;23:63. doi:10.1186/s12877-022-03581-8