There is compelling evidence of unmet need for eye care amongst older people with undetected vision loss . By the age of 65, 1 in 6 will become blind or partially sighted, and every day around 100 people in the UK start to lose their sight . Between 12 and 50% of older people have undetected visual loss, with higher prevalence amongst women and risk increasing rapidly with age. As the population ages the prevalence of vision loss from a range of eye disorders linked to ageing processes is likely to increase greatly .
A substantial proportion of this visual impairment is due to remedial causes such as refractive errors and cataracts. In the Medical Research Council’s study of screening older people refractive errors accounted for 32% of visual impairment in a 75 and over population. Causes of visual loss and eye disease in the rest of the visually impaired sample were: age related macular degeneration (AMD) (53%), cataract (36%), glaucoma (12%), myopic degeneration (4%) and diabetic eye disease (3%) . A north London study of 1547 people aged 65 and over found that 30% were visually impaired and that 72 % of this impairment could potentially be improved by surgery or spectacles .
The negative impact of visual impairment on quality of life, activities of daily living  and accidents, including falls , is also well documented, adding further weight to argument for focusing on prevention, early detection and timely access to treatment in this age group. The UK Vision Strategy , launched in April 2008, aims to improve the eye health of the nation by eliminating avoidable sight loss, supporting those with a visual impairment and enhancing the inclusion, participation and independence of blind and partially sighted people.
Whilst these aims are clearly desirable, methods of identifying those with unrecognised visual loss and encouraging them to take up services that will potentially improve their eyesight and quality of life are not well understood. The most recent update of the Cochrane review on screening for asymptomatic visual impairment shows that screening does not lead to improved vision in the older population .
It is not yet clear why remediable poor vision is being missed in an advanced primary care system with easily accessible doctors and nurses who can administer simple screening tests, and a widespread network of community optometrists who offer free NHS sight tests to older people. A review of the prevalence of visual impairment by the Royal National Institute for the Blind identified this problem as a priority for further investigation, highlighting issues of public perception and barriers to service access and utilisation . Given the lack of evidence of benefit for population screening, an alternative approach might be to foster case-finding in general practice, targeting vision assessments at individuals at highest risk of having undetected vision loss.
However, we do not know enough about the characteristics of people with un-assessed or untreated vision loss to be able to describe a clinically obvious group for targeted assessment. Although associations have been demonstrated between visual loss and age, wellbeing, functional ability, social networks and economic position in a descriptive study using data from the English longitudinal study on Ageing (ELSA) data , no adjustments were made in this study for confounding relationships and factors. Similarly, analysis of data from the Medical Research Council’s study of screening older people  which did make some adjustments for co-morbidities and functional ability is still insufficient to describe those with significant visual impairment in adequate detail.
This study is the sixth in a series on health risk appraisal in older people. Its objectives are to describe the characteristics of community dwelling people aged 65 and over who report poor vision but who have no established ophthalmological diagnosis, and to investigate the relative importance of socio-economic status, educational attainment, social relationships, co-morbidities, depressed mood, cognitive impairment and functional ability on self-reported poor vision and uptake of eye testing.