TY - JOUR
T1 - 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
AU - Bowen, M
AU - Edgar, D
AU - Hancock, B
AU - Haque, Mohammad
AU - Shah, R
AU - Buchanan, S
AU - Iliffe , S
AU - Maskell , S
AU - Pickett , J
AU - Taylor, J Paul
AU - O’Leary , N
PY - 2016/7
Y1 - 2016/7
N2 - Background: The prevalence of visual impairment (VI) and dementia increases with age and these
conditions may coexist, but few UK data exist on VI among people with dementia.
Objectives: To measure the prevalence of eye conditions causing VI in people with dementia and to
identify/describe reasons for underdetection or inappropriate management.
Design: Stage 1 – cross-sectional prevalence study. Stage 2 – qualitative research exploring participant,
carer and professional perspectives of eye care.
Setting: Stage 1 – 20 NHS sites in six English regions. Stage 2 – six English regions.
Participants: Stage 1 – 708 participants with dementia (aged 60–89 years): 389 lived in the community
(group 1) and 319 lived in care homes (group 2). Stage 2 – 119 participants.
Interventions: Stage 1 gathered eye examination data following domiciliary sight tests complying with
General Ophthalmic Services requirements and professional guidelines. Cognitive impairment was assessed
using the Standardised Mini-Mental State Examination (sMMSE) test, and functional ability and behaviour
were assessed using the Bristol Activities of Daily Living Scale and Cambridge Behavioural Inventory –
Revised. Stage 2 involved individual interviews (36 people with dementia and 11 care workers); and
separate focus groups (34 optometrists; 38 family and professional carers).
Main outcome measures.: VI defined by visual acuity (VA) worse than 6/12 or worse than 6/18 measured
before and after refraction.
DOI: 10.3310/hsdr04210 HEALTH SERVICES AND DELIVERY RESEARCH 2016 VOL. 4 NO. 21
© Queen’s Printer and Controller of HMSO 2016. This work was produced by Bowen et al. under the terms of a commissioning contract issued by the Secretary of State for
Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journals
provided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising. Applications for commercial reproduction should be
addressed to: NIHR Journals Library, National Institute for Health Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science
Park, Southampton SO16 7NS, UK.
vii
Results: Stage 1 – when participants wore their current spectacles, VI prevalence was 32.5%
[95% confidence interval (CI) 28.7% to 36.5%] and 16.3% (95% CI 13.5% to 19.6%) for commonly used
criteria for VI of VA worse than 6/12 and 6/18, respectively. Of those with VI, 44% (VA < 6/12) and 47%
(VA < 6/18) were correctable with new spectacles. Almost 50% of remaining uncorrectable VI
(VA < 6/12) was associated with cataract, and was, therefore, potentially remediable, and one-third was
associated with macular degeneration. Uncorrected/undercorrected VI prevalence (VA < 6/12) was
significantly higher in participants in care homes (odds ratio 2.19, 95% CI 1.30 to 3.73; p < 0.01) when
adjusted for age, sex and sMMSE score. VA could not be measured in 2.6% of group 1 and 34.2% of
group 2 participants (p < 0.01). The main eye examination elements (excluding visual fields) could be
performed in > 80% of participants. There was no evidence that the management of VI in people with
dementia differed from that in older people in general. Exploratory analysis suggested significant deficits in
some vision-related aspects of function and behaviour in participants with VI. Stage 2 key messages – carers
and care workers underestimated how much can be achieved in an eye examination. People with dementia
and carers were unaware of domiciliary sight test availability. Improved communication is needed between
optometrists and carers; optometrists should be informed of the person’s dementia. Tailoring eye
examinations to individual needs includes allowing extra time. Optometrists wanted training and guidance
about dementia. Correcting VI may improve the quality of life of people with dementia but should be
weighed against the risks and burdens of undergoing examinations and cataract surgery on an
individual basis.
Limitations: Sampling bias is possible owing to quota-sampling and response bias.
Conclusions: The prevalence of VI is disproportionately higher in people with dementia living in care
homes. Almost 50% of presenting VI is correctable with spectacles, and more with cataract surgery. Areas
for future research are the development of an eye-care pathway for people with dementia; assessment
of the benefits of early cataract surgery; and research into the feasibility of specialist optometrists for
older people.
Funding: The National Institute for Health Research Health Services and Delivery Research programme.
AB - Background: The prevalence of visual impairment (VI) and dementia increases with age and these
conditions may coexist, but few UK data exist on VI among people with dementia.
Objectives: To measure the prevalence of eye conditions causing VI in people with dementia and to
identify/describe reasons for underdetection or inappropriate management.
Design: Stage 1 – cross-sectional prevalence study. Stage 2 – qualitative research exploring participant,
carer and professional perspectives of eye care.
Setting: Stage 1 – 20 NHS sites in six English regions. Stage 2 – six English regions.
Participants: Stage 1 – 708 participants with dementia (aged 60–89 years): 389 lived in the community
(group 1) and 319 lived in care homes (group 2). Stage 2 – 119 participants.
Interventions: Stage 1 gathered eye examination data following domiciliary sight tests complying with
General Ophthalmic Services requirements and professional guidelines. Cognitive impairment was assessed
using the Standardised Mini-Mental State Examination (sMMSE) test, and functional ability and behaviour
were assessed using the Bristol Activities of Daily Living Scale and Cambridge Behavioural Inventory –
Revised. Stage 2 involved individual interviews (36 people with dementia and 11 care workers); and
separate focus groups (34 optometrists; 38 family and professional carers).
Main outcome measures.: VI defined by visual acuity (VA) worse than 6/12 or worse than 6/18 measured
before and after refraction.
DOI: 10.3310/hsdr04210 HEALTH SERVICES AND DELIVERY RESEARCH 2016 VOL. 4 NO. 21
© Queen’s Printer and Controller of HMSO 2016. This work was produced by Bowen et al. under the terms of a commissioning contract issued by the Secretary of State for
Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journals
provided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising. Applications for commercial reproduction should be
addressed to: NIHR Journals Library, National Institute for Health Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science
Park, Southampton SO16 7NS, UK.
vii
Results: Stage 1 – when participants wore their current spectacles, VI prevalence was 32.5%
[95% confidence interval (CI) 28.7% to 36.5%] and 16.3% (95% CI 13.5% to 19.6%) for commonly used
criteria for VI of VA worse than 6/12 and 6/18, respectively. Of those with VI, 44% (VA < 6/12) and 47%
(VA < 6/18) were correctable with new spectacles. Almost 50% of remaining uncorrectable VI
(VA < 6/12) was associated with cataract, and was, therefore, potentially remediable, and one-third was
associated with macular degeneration. Uncorrected/undercorrected VI prevalence (VA < 6/12) was
significantly higher in participants in care homes (odds ratio 2.19, 95% CI 1.30 to 3.73; p < 0.01) when
adjusted for age, sex and sMMSE score. VA could not be measured in 2.6% of group 1 and 34.2% of
group 2 participants (p < 0.01). The main eye examination elements (excluding visual fields) could be
performed in > 80% of participants. There was no evidence that the management of VI in people with
dementia differed from that in older people in general. Exploratory analysis suggested significant deficits in
some vision-related aspects of function and behaviour in participants with VI. Stage 2 key messages – carers
and care workers underestimated how much can be achieved in an eye examination. People with dementia
and carers were unaware of domiciliary sight test availability. Improved communication is needed between
optometrists and carers; optometrists should be informed of the person’s dementia. Tailoring eye
examinations to individual needs includes allowing extra time. Optometrists wanted training and guidance
about dementia. Correcting VI may improve the quality of life of people with dementia but should be
weighed against the risks and burdens of undergoing examinations and cataract surgery on an
individual basis.
Limitations: Sampling bias is possible owing to quota-sampling and response bias.
Conclusions: The prevalence of VI is disproportionately higher in people with dementia living in care
homes. Almost 50% of presenting VI is correctable with spectacles, and more with cataract surgery. Areas
for future research are the development of an eye-care pathway for people with dementia; assessment
of the benefits of early cataract surgery; and research into the feasibility of specialist optometrists for
older people.
Funding: The National Institute for Health Research Health Services and Delivery Research programme.
U2 - 10.3310/hsdr04210
DO - 10.3310/hsdr04210
M3 - Article
SN - 2050-4349
VL - 4
JO - Health Services and Delivery Research
JF - Health Services and Delivery Research
IS - 21
ER -