Prevalence of ocular disease and blindness in a rural area in the eastern region of Iceland during 1980 through 1984

Prevalence of age-related macular degeneration in an elderly UK Caucasian population-The Bridlington Eye Assessment Project: a cross-sectional study

ImportanceThere is paucity of data on prevalence and disease asymmetry of age-related macular degeneration (AMD), particularly the earlier stages, in the UK population.Objective and PurposeTo determine the prevalence of age-related macular degeneration in an elderly Caucasian UK population.DesignCross-sectional population study, 2002-2006.ParticipantsResidents in the study area of Bridlington aged 65 years and older.MethodsFull-ophthalmic examination was undertaken in 3549 participants, of eligible 6319 Caucasian population (response rate of 56%). Non-stereoscopic Colour fundus photographs (30°) were graded masked using a modified Rotterdam Classification for 3475 (98%) participants with gradable images. Prevalence for different AMD grades were calculated. Demographic details were analysed then integrated with the AMD gradings for full analysis. Prevalence rates for the different AMD Grades were calculated, as well as the age-specific prevalences.ResultsAMD prevalence in the worst eye were 38.5% grade 0, 41.4% grade 1, 12.8% grade 2, 2.8% grade 3, and 4.6% grade 4. Geographic atrophy (grade 4a) occurred in 2.5%, and neovascular AMD (grade 4b) in 1.8%. Prevalence increased with age such that grade 4 (advanced) AMD was 2.2% in the 65-69 years group, 15.8% for the 85-90, and 21.2% for over 90 years. There was significant asymmetry between the two eyes of individuals with advanced AMD (P<0.001), such that vision loss was unilateral. Persons with more advanced AMD grades were more likely to be dissatisfied with their vision.ConclusionsAdvanced AMD occurs more commonly in the UK Caucasian population than previously reported. Significant asymmetry between the two eyes occurs in individuals with unilateral advanced AMD so that visual impairment statistics do not represent true prevalence of advanced AMD. Persons with more advanced AMD were more likely to be dissatisfied with their vision.

Prevalence of age-related macular degeneration in old persons: Age, Gene/environment Susceptibility Reykjavik Study

PURPOSE

To describe the prevalence and signs of early and late age-related macular degeneration (AMD) in an old cohort.

DESIGN

Population-based cohort study.

PARTICIPANTS

We included 5272 persons aged ≥66 years, randomly sampled from the Reykjavik area.

METHODS

Fundus images were taken through dilated pupils using a 45-degree digital camera and graded for drusen size, type, area, increased retinal pigment, retinal pigment epithelial depigmentation, neovascular lesions, and geographic atrophy (GA) using the modified Wisconsin Age-Related Maculopathy Grading System.

MAIN OUTCOME MEASURES

Age-related macular degeneration in an elderly cohort.

RESULTS

The mean age of participants was 76 years. The prevalence of early AMD was 12.4% (95% confidence interval [CI], 11.0-13.9) for those aged 66 to 74 years and 36% (95% CI, 30.9-41.1) for those aged ≥85 years. The prevalence of exudative AMD was 3.3% (95% CI, 2.8-3.8). The prevalence of pure GA was 2.4% (95% CI, 2.0-2.8). The highest prevalence of late AMD was among those aged ≥85 years: 11.4% (95% CI, 8.2-14.5) for exudative AMD and 7.6% (95% CI, 4.8-10.4) for pure GA.

CONCLUSIONS

Persons aged ≥85 years have a 10-fold higher prevalence of late AMD than those aged 70 to 74 years. The high prevalence of late AMD in the oldest age group and expected increase of elderly people in the western world in coming years call for improved preventive measures and novel treatments.

Characteristics of dynamic processing in the visual field of patients with age-related maculopathy

Purpose

To investigate the characteristics of dynamic processing in the visual field of patients with age-related maculopathy (ARM) by measuring motion sensitivity, double-pulse resolution (DPR), and critical flicker fusion.

Methods

Fourteen subjects with ARM (18 eyes), 14 age-matched controls (19 eyes), and 7 young controls (8 eyes) served as subjects. Motion contrast thresholds were determined by a four-alternative forced-choice (4 afc) staircase procedure with a modification by Kernbach for presenting a plaid (size = 3.8°) moving within a stationary spatial and temporal Gaussian envelope in one of four directions. Measurements were performed on the horizontal meridian at 10°, 20°, 30°, 40°, and 60° eccentricity. DPR was defined as the minimal temporal gap detectable by the subject using a 9-fold interleaved adaptive procedure, with stimuli positioned on concentric rings at 5°, 10°, and 20° eccentricity on the principal and oblique meridians. Critical flicker fusion thresholds (CFF) and the Lanthony D-15 color vision test were applied foveally, and the subjects were free to use their fovea or whatever retinal area they needed to use instead, due to their retinal lesions caused by ARM. All measurements were performed under photopic conditions.

Results

Motion contrast sensitivity in subjects with ARM was pronouncedly reduced (0.23–0.66 log units, p < 0.01), not only in the macula but in a region up to 20° eccentricity. In the two control groups, motion contrast sensitivity systematically declined with retinal eccentricity (0.009–0.032 log units/degree) and with age (0.01 log units/year). Double-pulse thresholds in healthy subjects were approximately constant in the central visual field and increased outside a radius of 10° (1.73 ms/degree). DPR thresholds were elevated in subjects with ARM (by 23–32 ms, p < 0.01) up to 20° eccentricity, and their foveal CFFs were increased by 5.5 Hz or 14% (p < 0.01) as compared with age-matched controls.

Conclusions

Dynamic processing properties in subjects with ARM are severely impaired in the central visual field up to 20° eccentricity, which is clearly beyond the borders of the macula.

The prevalence of eye disease in nursing home and non-nursing home geriatric populations

The objective of this study was to determine whether rates of eye disease among the elderly are higher for residents of nursing homes than for persons who reside elsewhere. Articles reporting the prevalence of eye disease in geriatric populations (classified as nursing home or non-nursing home) were identified through a Medline search and a search of articles' bibliographies. Identified articles were reviewed, and the relevant data compared with prevalence rates obtained from 738 residents of two nursing homes in New York City. Each of the nursing home residents received an ocular examination upon admission that determined the presence or absence of four varieties of eye disease-i.e. cataracts, age-related macular degeneration, glaucoma, and diabetic retinopathy. Demographic data were obtained through chart review. Results indicate that prevalence rates of eye disease found in geriatric nursing home populations are generally higher than those found in other geriatric populations. With the exception of the rates for diabetic retinopathy, the rates found in the combined nursing home population sampled in this study were much higher than those reported in any previous study. It is concluded that eye disease is a more serious problem for elderly residents of nursing homes than for the elderly who reside in the community. Possible reasons for this are discussed.

Patients' perceptions of the value of current vision: assessment of preference values among patients with subfoveal choroidal neovascularization--The Submacular Surgery Trials Vision Preference Value Scale: SST Report No. 6

OBJECTIVE

To improve understanding and awareness of the impact of subfoveal choroidal neovascularization (CNV) on health-related quality of life, we sought to measure the preference value that patients with subfoveal CNV assigned to their health and vision status.

PATIENTS AND METHODS

Patients with subfoveal CNV completed telephone interviews about their quality of life prior to enrollment and random treatment assignment in the Submacular Surgery Trials, a set of multicenter randomized controlled trials evaluating outcomes of submacular surgery compared with observation. The interviewers asked patients to rate their current vision on a scale from 0 (completely blind) to 100 (perfect vision). The interviewers also asked them to rate complete blindness and then perfect vision, assuming their health otherwise was the same as it was at the time of the interview, on a scale from 0 (dead) to 100 (perfect health with perfect vision). Scores were converted to a 0 to 1 preference value scale for health and vision status, where 0 represents death and 1 represents perfect health and vision.

RESULTS

Of 1015 participants enrolled in the Submacular Surgery Trials, 996 completed interviews that included the rating questions, and 792 (80%) answered all 3 rating questions in a manner permitting calculation of a single overall preference value for their current health and vision status on a scale from 0 (dead) to 1 (perfect). The mean preference value was 0.64 (median, 0.68; interquartile range, 0.51-0.80). The preference values correlated with age (Pearson correlation coefficient, -0.11; P = .002), patients' self-rated perception of overall health (Spearman correlation coefficient, 0.36; P<.001), and self-reported perception of vision (Spearman correlation coefficient, 0.47; P<.001). The preference values were significantly lower with poorer visual acuity in the better eye and greater evidence of dysfunction on either the Hospital Anxiety and Depression Scale or the Physical or Mental Component Summary scales of the Short Form-36 Health Survey but did not differ significantly by gender or other baseline characteristics such as race, treatment assignment, or size of the CNV lesion.

CONCLUSIONS

Vision loss from subfoveal CNV is associated with patient preference values that are as low as or lower than values previously reported for other serious medical conditions such as dialysis-dependent renal failure and AIDS, indicating that both unilateral and bilateral CNV have a profound impact on how patients feel about their overall health-related quality of life.

The prevalence and incidence of visual impairment in people of age 20-59 years in industrialized countries: a review

BACKGROUND

Reviews on the prevalence of blindness and low vision in persons of age 20 to 59 years are lacking. We have therefore carried out a review based on a Medline search.

METHODS

The review was confined to epidemiological studies performed in Western Europe, North America and Australia covering the age group 20 to 59 years where there were comparable definitions of blindness and low vision according to the IAPB and WHO classification of blindness and low vision.

RESULTS

Three surveys, four register studies and two studies based on multiple sources matched our selection criteria. Blindness and low vision are described separately. Blindness: Only one study, based on multiple sources, covered the whole age group 20 to 59 years. In this study the overall prevalence of blindness was 0.08%. The prevalence of blindness was 0.04% among those 20-39 years old, whereas in the age group 40-59 years it was 0.1% in two surveys and one study on multiple sources. However, the prevalence was higher, 0.5% among whites and 0.7% among colored, in The Baltimore Eye Study. The definition of blindness was similar in all three studies. Low vision: Three studies provided data on the prevalence of low vision in the age group 20-59 years, although the number of cases was very small. In one study the prevalence of a visual acuity < or = 6/24 to 6/48 was 0.07% and in another the prevalence was 0.17% using < 6/18 to 0.5/60. No person with low vision was found in the third study.

CONCLUSIONS

The existing epidemiological data on blindness and low vision among adults aged 20 to 59 years are insufficient. Epidemiological studies based on multiple sources are needed for the study of rare conditions such as blindness and low vision.

Dissection of genomewide-scan data in extended families reveals a major locus and oligogenic susceptibility for age-related macular degeneration

To examine the genetic basis of age-related macular degeneration (ARMD), a degenerative disease of the retinal pigment epithelium and neurosensory retina, we conducted a genomewide scan in 34 extended families (297 individuals, 349 sib pairs) ascertained through index cases with neovascular disease or geographic atrophy. Family and medical history was obtained from index cases and family members. Fundus photographs were taken of all participating family members, and these were graded for severity by use of a quantitative scale. Model-free linkage analysis was performed, and tests of heterogeneity and epistasis were conducted. We have evidence of a major locus on chromosome 15q (GATA50C03 multipoint P=1.98x10-7; empirical P< or =1.0x10-5; single-point P=3.6x10-7). This locus was present as a weak linkage signal in our previous genome scan for ARMD, in the Beaver Dam Eye Study sample (D15S659, multipoint P=.047), but is otherwise novel. In this genome scan, we observed a total of 13 regions on 11 chromosomes (1q31, 2p21, 4p16, 5q34, 9p24, 9q31, 10q26, 12q13, 12q23, 15q21, 16p12, 18p11, and 20q13), with a nominal multipoint significance level of P< or =.01 or LOD > or =1.18. Family-by-family analysis of the data, performed using model-free linkage methods, suggests that there is evidence of heterogeneity in these families. For example, a single family (family 460) individually shows linkage evidence at 8 loci, at the level of P<.0001. We conducted tests for heterogeneity, which suggest that ARMD susceptibility loci on chromosomes 9p24, 10q26, and 15q21 are not present in all families. We tested for mutations in linked families and examined SNPs in two candidate genes, hemicentin-1 and EFEMP1, in subsamples (145 and 189 sib pairs, respectively) of the data. Mutations were not observed in any of the 11 exons of EFEMP1 nor in exon 104 of hemicentin-1. The SNP analysis for hemicentin-1 on 1q31 suggests that variants within or in very close proximity to this gene cause ARMD pathogenesis. In summary, we have evidence for a major ARMD locus on 15q21, which, coupled with numerous other loci segregating in these families, suggests complex oligogenic patterns of inheritance for ARMD.

How big is the burden of visual loss caused by age related macular degeneration in the United Kingdom?

AIMS

To predict the burden of blindness, partial sight, and visual impairment (binocular visual acuity 6/18 or less) due to late stage age related macular degeneration (AMD) in the ageing population of the United Kingdom.

METHODS

A systematic review, followed by a request for data, was used to establish a pooled prevalence of AMD and corresponding visual loss. Prevalence figures were applied to the UK population. Using UK population trends, the future burden of AMD over the coming decade was established.

RESULTS

Pooled data from six studies showed that the prevalence of visual loss caused by AMD increased exponentially from the age of 70-85 years of age, with 3.5% (95% CI 3.0 to 4.1) having visual impairment beyond the age of 75 years. The authors estimate that there are currently 214 000 (95% CI 151 000 to 310 000) with visual impairment caused by AMD (suitable for registration). This number is expected to increase to 239 000 (95% CI 168 000 to 346 000) by the year 2011. Currently there are 172 000 (95% CI 106 000 to 279 000) and 245 000 (95% CI 163 000 to 364 000) with geographical and neovascular AMD, respectively.

CONCLUSIONS

Estimates of visual impairment agree with official statistics for the number registered partially sighted or blind, caused by AMD, and are well below other figures often cited. Although these estimates are associated with wide confidence intervals (CI) and a number of caveats, they represent the best available data, which can be used to guide health and social care provision for older people in the UK setting. Implications for low vision services are outlined.

Body mass index and the incidence of visually significant age-related maculopathy in men

BACKGROUND

Reports have suggested relationships of body weight with age-related maculopathy (ARM), particularly its nonneovascular (dry) forms, but results are inconsistent and prospective data are scarce.

OBJECTIVE

To examine prospectively relationships of body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) with visually significant dry and neovascular ARM during an average of 14.5 years of follow-up.

METHODS

Incident ARM was assessed by medical record confirmation of self-reported ARM among the 21 121 men participating in the Physicians' Health Study who (1) were followed up for at least 7 years, (2) were free of visually significant ARM at baseline, and (3) had information on BMI and cigarette smoking. We used proportional hazards regression models to estimate rate ratios (RRs) and 95% confidence intervals (CIs) for visually significant dry ARM (256 cases) and neovascular ARM (84 cases) within 4 categories of BMI: lean (< 22.0), normal (22.0-24.9), overweight (25.0-29.9), and obese (> or = 30.0).

RESULTS

Adjusting for age, randomized aspirin and beta carotene assignments, and cigarette smoking, the incidence for visually significant dry ARM was lowest in men with a normal BMI. Compared with these men, the RRs (95% CIs) were as follows: 1.43 (1.01-2.04) for lean, 1.24 (0.93-1.66) for overweight, and 2.15 (1.35-3.45) for obese men. Although there was no significant relationship of BMI with the diagnosis of neovascular ARM, due to the small number of cases these analyses could not rule out an important relationship.

CONCLUSIONS

Obesity is a risk factor for visually significant ARM in men, in particular for dry ARM. However, the relationship of BMI with dry ARM appears to be J-shaped, and the leanest individuals also appear to be at increased risk.