Table 2.
Prevalence of visual impairment in people with dementia in the community, nursing homes, and hospitals or other healthcare settings
| Study and Year | Setting | Age (years) | Definition of VI or eye disease | Method of measurement of VI or eye disease | Prevalence (%) |
|---|---|---|---|---|---|
| Visual impairment | |||||
| Abdullah, 196522a | Community | ≥ 65 | Ability to read or not | Not described |
Patient in long-stay ward: 33.76% Patient seen in domiciliary visit: 12.4% |
| Amjad, 2019 [13] | Community | ≥65; Mean: 82.3 ± 8.1 | Categorised based on responses to the following: ‘Uses corrective lenses or blind’, ‘Sees well enough to recognize person across street’, ‘Can watch TV across room’, ‘Reads newspaper print’. Presence of hearing or vision impairment measured yes/no Sensory symptom burden score range 0–8. Deaf or blind = 4 points. Each difficulty = 1 point | Self-reported | About 34% |
| Bowen, 2016 [17] | Community | 60–89 | Visual acuity worse than 6/12 or worse than 6/18 measured before and after refraction. | Ophthalmologist assessment |
With spectacles and VA < 6/12: 32.5% With spectacles and VA < 6/18: 16.3% |
| Chandra, 1986 [19] | Community | Mean: 80.1 | Listed as a cause of death | Death certificate | Blindness: 0.4% |
| Chriqui, 2017 [20] | Nursing home | ≥ 65; Mean: 87.2 ± 7.5 | A distance VA lower than 6/12 (0.30 logMAR, 20/40) in the better seeing eye | Ophthalmologist assessment | 37.3% (95% CI, 29.1 to 46.1) |
| Deardorff, 2019 [23] | Community | ≥65 | Based on the question: How much trouble do you have with your vision? (no trouble, little trouble, or a lot of trouble). Subjects who reported “little trouble” or “a lot of trouble” were classified as visually impaired | Self-reported | 45.9% |
| Kang, 2012 [28] | Nursing home | ≥ 60 | MDS-Activities of Daily Living (MDS-ADLs). Visual function was assessed by MDS section D1 Vision, which is a five-level ordinal variable scale (i.e., adequate, moderately impaired, impaired, highly impaired, and severely impaired). “Vision” refers to the ability to see in adequate light and with glasses. | Self-reported |
Impaired: 22.2% Moderately impaired: 7.2% Highly impaired: 10.5% Severely impaired:1.3% In total: 41.2% |
| Kiely, 2018 [29] | Community | ≥65; Mean: 75.3 ± 1.5 | Sensory loss was defined by visual acuity worse the 0.3 logMAR (6/12 or 20/40) | Ophthalmologist assessment | 15.4% |
| Luo, 2018 [33] | Community | Not described | WHO best–corrected visual acuity (BCVA) criteria (low vision: 0.05 ≤ BCVA ≤0.29; blindness: no light perception ≤ BCVA < 0.05, visual field less than 10 degrees; the better- seeing eye). | Ophthalmologist assessment | 16.4% |
| Marquie, 2019 [34] | Community | Mean: 81.4 ± 7.2 | Reduced visual acuity was defined as a standard LogMAR fraction scale ≤20/50 at 20 ft. (equivalent to a fraction scale of 6/15 at 6 m and a decimal scale of 0.4) according to the Snellen scale | Ophthalmologist assessment | Low VA: 37% |
| Morse, 2004 [35] | Nursing home | Mean: 84 | VA was grouped into five categories: normal VI (20/20–20/40), mild VI (20/50–27,170), moderate VI (20/80–20/200), severe VI (20/250 20/1000), and very severe VI (counting fingers, hand motion, or no light perception). | Ophthalmologist assessment |
Mild VI: 16.9% Moderate VI: 22.8% Severe VI: 11.8% Very severe VI: 0.2% In total: 51.6% |
| Muurine, 2014 [36] | Nursing home | > 65; Mean: 83 | Residents’ vision was assessed by a question “Is the resident’s vision good enough for reading regular print” (yes/no) (with or without glasses). Those responding “no” were defined as visually impaired. | Self-reported | 19.7% |
| Prince, 2011 [40] | Community | ≥ 65 | Eyesight problems which result in at least some difficulty, and/or an observer-rated item by the interviewer of ‘near total blindness’ | Self-reported/observer-rated |
Latin America Questionable dementia 42.3% Mild dementia 45.5% Moderate or severe dementia 39.6% India Questionable dementia 21.6% Mild dementia 16.2% Moderate or severe dementia 0% China Questionable dementia 12.9% Mild dementia 16.1% Moderate or severe dementia 20.9% |
| Clague, 2017 [22] | Community | Mean: 82.6 ± 7.4; | Identified open angle glaucoma cases by the principal diagnosis of ICD-9-CM codes 365.1, 365.10, or 365.11 | Medical claim during ambulatory care visits | Blindness/low vision 4.0% |
| Hamedani, 2019 [25] | Community | Not described | Blindness/low vision was defined by ICD-9 diagnosis codes (369.0–369.4). | Claims data |
Blindness/low vision AD: 23.9% Dementia NOS: 50.0% |
| Kosse, 2015 [30] | Nursing home | Not described | Categorized according to the anatomical therapeutic chemical (ATC) classification system | Medical records | Visual problems: 45% |
| Wittich, 2019 [45] | Not described | Not described | Reduced reading acuity: > .5 logMAR [20/63] | Ophthalmologist assessment | Reduced VA: 23.80% |
| AMD | |||||
| Bowen, 2016 [17] | Community | 60–89 | AMD was classified into dry and wet (neovascular) AMD and then graded as mild, moderate or severe. | Ophthalmologist assessment and medical records | 17.7% |
| Carcenac, 2019 [18] | Nursing home | Not described | Not described | Medical records |
Reported in records: 13.6% Discovered in eye exam: 23.1% |
| Frost, 2016 [31] | Community | Mean: 70.2 ± 9.0 |
Classified according to the Beckman system: No clinically relevant signs of AMD: Small drusen or no drusen, no pigmentary abnormalities. Early AMD: Medium drusen without pigmentary abnormalities. Intermediate AMD: Large drusen, or Medium drusen with pigmentary abnormalities Late AMD: Lesions associated with neovascular AMD or geographic atrophy |
Ophthalmologist assessment |
Early AMD: 36% Intermediate AMD: 4.5% Late AMD: 0 Total AMD: 40.9% |
| Marquie, 2019 [34] | Community | Mean: 81.4 ± 7.2 | Diagnoses of dry and wet AMD were based on the Age-Macular Degeneration Preferred Practice Patterns guidelines; used the classification of the Age-Related Eye Disease Study and a more recent classification to define the early and intermediate stages of AMD | Ophthalmologist assessment | 4.8% |
| Smilnak, 2019 [41] | Hospital | ≥ 75; Mean: 88.6 ± 5.9 | AMD was defined as Sarks grades III-VI, corresponding to intermediate to severe clinical AMD | Autopsy | 53% |
| Williams, 2014 [44] | Other healthcare setting | Mean: 80.1 ± 7.7 | The AMD grading system was as the “Whitla grades” | Ophthalmologist assessment |
Grade 0: 47.3% Grade 1: 0.9% Grade 2: 7.8% Grade 3: 8.1% Ungraded: 19.4% |
| Wong, 2015 [46] | Not described | > 60 | Assessed AMD using standard grading systems (not described) | Ophthalmologist assessment | 27% |
| Cataract | |||||
| Abdullah, 1965 [12] | Community | ≥ 65 | Not described | Not described | 48% |
| Bowen, 2016 [17] | Community | 60–89 | Cataract sufficient to be graded on the TOC cataract grading scale. | Ophthalmologist assessment and medical records | 59% |
| Chandra, 1986 [19] | Community | Mean: 80.1 | Not described | Medical records | 0.2% |
| John, 1999 [27] | Community | Mean 84.7 (73.6–96.4) | Not described | Medical records | 22.8% |
| Löppönen, 2004 [32] | Community | Mean 82.4 ± 7 | Based on ICD-10 codes | Medical records | 21% |
| Wong, 2015 [46] | Not described | > 60 | Assessed using standard grading systems (not described) | Ophthalmologist assessment | 74% |
| Diabetic retinopathy | |||||
| Bowen, 2016 [17] | Community | 60–89 | Not described | Ophthalmologist assessment | 2% |
| Wong, 2015 [46] | Not described | > 60 | Assessed using standard grading systems (not described) | Ophthalmologist assessment | 19% |
| Glaucoma | |||||
| Bayer, 2002 [14] | Nursing home |
With glaucoma; Mean: 72.9 ± 10.6 Without glaucoma Mean: 71.4 ± 11.9 |
The diagnosis of probable glaucoma required at least one of the following two criteria: - A characteristic pattern of glaucomatous visual field loss; A cup-to-disk ratios of 0.8 or greater with an optic nerve head appearance consistent with glaucoma. |
Ophthalmologist assessment | 25.9% |
| Bayer, 2002 [15] | Nursing home |
With glaucoma: Mean: 71.9 ± 11.6 Without glaucoma: Mean: 73.2 ± 12.3a |
The diagnosis of probable glaucoma required at least one of the following two criteria: - A characteristic pattern of glaucomatous visual field loss; - A cup-to-disk ratios of 0.8 or greater with an optic nerve head appearance consistent with glaucoma. |
Ophthalmologist assessment | 24.5% |
| Bowen, 2016 [17] | Community | 60–89 | Not described | Ophthalmologist assessment | 7.1% |
| Carcenac, 2019 [18] | Nursing home | Not described | Not described | Medical records |
Reported in records: 12.7% Discovered in eye exam: 22.2% |
| Chandra, 1986 [19] | Community | Mean: 80.1 | Not described | Medical records | 0.2% |
| Chung, 2015 [21] | Community | ≥45; Mean: 76.8 ± 9.6 | Based on ICD-9-CM codes 365.1, 365.10, or 365.11 | Medical records | 2.02% |
| Heun, 2013 [26] | Hospital | Mean: 85.1 ± 8.2; | Based on ICD-10 codes | Medical records | 1.1% |
| Lai, 2017 [31] | Community | ≥45; Mean: 78.7 ± 6.6 | Based on ICD-9 codes 365.1 and 365.2 | Medical records | 7.9% |
| Löppönen, 2004 [32] | Community | Mean 82.4 ± 7 | Based on ICD-10 codes | Medical records | 6% |
| Marquie, 2019 [34] | Community | Mean: 81.4 ± 7.2 | The glaucoma category was based on the image of the head of the optic nerve (ONH), ONH OCT findings and Icare IOP measurements; High IOP was defined as ≥24 mmHg using Icare Tonometry | Ophthalmologist assessment |
Glaucoma: 7.7% High IOP: 6.5% |
| Pelletier, 2014 [39] | Hospital | Mean: 83.7 ± 6.3; | Not described | Medical records | 9.5% |
| Smilnak, 2019 [41] | Hospital | ≥ 75; Mean: 88.6 ± 5.9 | The histopathologic diagnosis of advanced glaucoma was made when the following were observed: sparse retinal ganglion cells, diminished size of optic nerve axon bundles, and fibrotic thickening or “cupping” of the optic nerve | Medical records | Glaucoma (severe): 13.9% |
| Tamura, 2006 [42] | Nursing home | Mean: 80.9 ± 8.4 | Probable OAG was diagnosed by width of the angle of the anterior chamber >grade 2, a vertical cup-to-disc ratio of the optic nerve head > 0.7 and/or difference between the vertical cup-to-disc ratio in the eyes > 0.2 with characteristic glaucomatous disc change. | Ophthalmologist assessment | 23.8% |
| Wong, 2015 [46] | Not described | > 60 | Optic disc features of glaucoma | Ophthalmologist review of retinal photographs | 15% |
Abbreviation: VA Visual acuity, USA The United States, UK The United Kingdom, CI Confidence interval, VI Visual impairment, AD Alzheimer’s diseases, Dementia NOS Dementia (not otherwise specified), AMD Aged-macular degeneration, IOP Intraocular pressure
aAuthors reported this as incidence of cataract but based on the methods described it is most likely an estimate of prevalence