NIHR Signal A third of people with dementia have treatable vision problems
Published on 27 September 2016
New data shows that around a third of people with dementia have serious vision problems, such as cataracts or short sightedness, more than the general population of that age. Levels are higher still for people with dementia in care homes – about half have vision problems.
Yet this study showed that many of the people with dementia and vision impairment had not received the right treatment. This often involves simple measures. For many, spectacles could have improved poor sight. A quarter had cataracts, which surgery could have corrected. Quality of life is known to improve if visual impairment is corrected.
Failure to receive treatment may be due to lack of awareness amongst people with dementia and their carers about the services available to them, as well as concerns about the impact of enforced spectacle wearing and surgery.
Eye examination professionals need to tailor their approach according to the needs of the individual, involving carers as far as possible. These patients would also benefit from longer consultation times.
- Eyes and vision, Health management, Older people, Dementia
Why was this study needed?
Dementia describes a set of symptoms that can include memory loss, language difficulties and reduced thinking speed. In the UK, 850,000 people are living with dementia. Of those, at least 123,000 older people also have visual impairment.
Having both conditions seriously affects quality of life and ability to conduct everyday activities and maintain independence. In addition, those with dementia may be less likely to seek or be able to access eye care meaning that many sight conditions may be going undiagnosed and untreated.
This NIHR-funded study sought to understand the true extent of the problem and gain a better understanding of how to address it for people with dementia living in their own homes and care homes.
What did this study do?
PrOVIDe was the largest population type study of eye problems for people with dementia living in different settings. Stage one was a cross-sectional study to estimate how common vision problems are in people with dementia. Optometrists performed eye examinations on 708 people aged 60 to 89 from 20 NHS sites in England covering rural, urban and city locations. Examinations took place at home for 389 people and in care homes for 319.
Stage two explored attitudes and issues about the detection and management of vision problems. Researchers interviewed 36 people with dementia, 30 carers and 11 care workers individually. Five focus groups with family carers, five with optometrists and one with care workers explored these issues in depth.
Missing data was accounted for as far as possible in the statistical analysis.
What did it find?
- Nearly one-third of participants in whom vision could be measured were visually impaired, 191 out of 708 people, (32.5%, 95% confidence interval [CI)] 28.7 to 36.5). Vision problems were even more common in those living in care homes - present in over half of those tested.
- 80% of participants completed the key parts of the examination.
- The correct spectacles could have improved the sight of 84 of 586 participants with visual acuity less than 6/12 (14.3%, 95% CI 11.7 to 17.5).
- Cataract was responsible for almost half of the cases of continued visual impairment despite correct spectacles, 49 out of 102 (48.0%, 95% CI 38.1% to 58.1%), so these cases were potentially correctable with surgery.
- Awareness of home vision examination services was low among those with dementia and their carers. Almost 25% of participants had not had an eye examination in the previous 2 years.
- Focus groups raised the need to weigh the benefits of intervention against the possible distress caused by eye examinations, forcing people to wear spectacles, or cataract surgery. They highlighted the need to take account of individual’s preference and/or that of their carer.
What does current guidance say on this issue?
NHS sight tests are recommended annually for people over 70.
NICE guidance on dementia does not cover vision problems, but does stress the need for individualised person-centred care. In addition, it states the need to acknowledge and value carers’ input.
In terms of services for vision problems in people with dementia, the Royal College of Ophthalmologists has a 2015 quality standard. While it focuses on an ophthalmology department setting, it provides information regarding making eye examinations more acceptable and successful for people with dementia. Advice includes offering longer consultation times and accessible information about vision and eye care.
What are the implications?
Ensuring professionals conducting eye examinations have appropriate support and training should help promote the range of services available to people with dementia and their carers.
Correcting vision problems could improve quality of life, save money and potentially reduce harms such as falls. This could allow people with dementia to retain their independence for longer.
Lowering the threshold for cataract surgery for people with dementia may enable them to have surgery before their illness becomes too severe and while they are still able to make informed decisions.
Citation and Funding
Bowen M, Edgar DF, Hancock B, et al. The Prevalence of Visual Impairment in People with Dementia (the PrOVIDe study): a cross-sectional study of people aged 60–89 years with dementia and qualitative exploration of individual, carer and professional perspectives. Health Serv Deliv Res. 2016;4(21).
This project was funded by the National Institute for Health Research (Health Services and Delivery Research [HS&DR] programme) (Project number 11/2000/13).
Alzheimer's Society. Dementia 2014 infographic. London: Alzheimer's Society; 2014.
NHS Choices. Dementia. London: Department of Health; 2015.
NHS Choices. NHS eyecare services. London: Department of Health; 2014.
NICE. Dementia: supporting people with dementia and their carers in health and social care. CG42. London: National Institute for Health and Care Excellence; 2016.
Royal College of Ophthalmologists. Quality standard for people with sight loss and dementia in an ophthalmology department London: Royal College of Ophthalmologists; 2015.
This study shows that there are about 100,000 people in the UK with dementia who are wearing the wrong prescription glasses, and that's a conservative estimate. Something as simple as addressing eye care for people with dementia offers potentially huge gains in quality of life at little cost. Also to note is the 50,000 (approximately) people with dementia that have untreated cataract - further work should be carried out to understand when cataract surgery is appropriate.
Matt Murray, Research Engagement Manager, Alzheimer's Society
Optometrists are trained to recognise, treat and manage abnormalities and signs of some, but not all, eye diseases. Like eye surgeons (ophthalmologists), they examine the internal and external structure of the eyes to detect diseases like glaucoma, macular degeneration, and cataracts. They may also test a person's ability to focus and coordinate the eyes and see depth and colours accurately. Optometrists do not perform surgery.
Visual acuity is the central vision used to see detail. It is measured using the Snellen scale. On the Snellen scale, normal visual acuity is called 6/6. Having 6/12 vision means you can see at six metres what a person with normal vision can see at 12 metres away.