Melbourne Visual Impairment Project Research Articles

Change in the prevalence of myopia in Australian middle-aged adults across 20 years.

The prevalence of myopia is increasing globally including in Europe and parts of Asia but Australian data are lacking. This study aim described the change in myopia prevalence in middle-aged Australian adults over approximately a 20-year period. Two contemporary Western Australian studies (conducted in mid-late 2010s): the coastal-regional Busselton Healthy Ageing Study (BHAS) and the urban Gen1 of the Raine Study (G1RS) were compared to two earlier studies (early-mid 1990s) in Australia: the urban Blue Mountains Eye Study (BMES) and urban/regional Melbourne Visual Impairment Project (MVIP). Refractive error was measured by autorefraction, vertometry, or subjective refraction. Participants (49-70 years) of European descent without self-reported/diagnosed cataract, corneal disease, or refractive or corneal surgery were included. After exclusions, data were available from 2217, 1760, 700, 2987 and 756 participants from BMES, urban MVIP, regional MVIP, BHAS, and G1RS, respectively. The mean age ranged from 57.1 ± 4.6 years in the G1RS to 60.1 ± 6.0 years in the BMES; 44-48% of participants were male. When stratified by location, the contemporary urban G1RS cohort had a higher age-standardised myopia prevalence than the urban MVIP and BMES cohorts (29.2%, 16.4%, and 23.9%, p< 0.001). The contemporary coastal-regional BHAS had a higher age-standardised myopia prevalence than the regional MVIP cohort (19.4% vs. 13.8%, p= 0.001). We report an increase in myopia prevalence in older adults in Australia born after World War ll compared to cohorts born before, accounting for urban/regional location. The prevalence of myopia remains relatively low in middle-aged Australian adults.

A population-based estimate of cataract prevalence: the Melbourne Visual Impairment Project experience.

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Carbohydrate nutrition and cataract

Studies suggest dietary carbohydrates play a role in cataractogenesis. Objective: examine the cross‐sectional associations between total carbohydrate intake, dietary glycemic index and the risk for cortical and nuclear cataract.1609 eligible non‐diabetic participants in the Melbourne Visual Impairment Project were used. Dietary information derived from a food frequency questionnaire and cataract status graded by the Wilmer protocol were collected. Using generalized estimating approach to logistic regression to account for the lack of independence between two eyes of an individual, we examined the associations between dietary carbohydrate and risk for cataract for eyes with no or a single type(pure) of cataract.After multivariate adjustment, pure cortical cataract was significantly associated with total carbohydrate intake (odds ratio comparing the highest quartile with the lowest quartile = 3.19, 95% confidence interval 1.10, 9.27; P for trend = 0.017). The OR for nuclear cataract (366 eyes) comparing the third quartile of dGI with the first quartile, but there was not a consistent dose‐response association.Carbohydrate intake may be optimized to prolong eye lens function

Dietary carbohydrate in relation to cortical and nuclear lens opacities in the melbourne visual impairment project.

In vitro and in vivo animal studies suggest that dietary carbohydrates play a role in cataractogenesis. Few epidemiologic studies have been conducted to evaluate this association. The objective of this study was to examine the cross-sectional associations between total carbohydrate intake, dietary glycemic index (dGI), and the risk of cortical and nuclear cataracts. After excluding 864 persons from 2473 eligible participants, 1609 eligible nondiabetic participants (mean age, 57.6 years, 55.9% female) in the Melbourne Visual Impairment Project (VIP) were enrolled. Dietary information derived from a semiquantitative food-frequency questionnaire and cataract status graded by the Wilmer protocol (cortical cataract: opacity >or=4/16; nuclear cataract grade >or=2) were collected. With the use of the generalized estimating approach to logistic regression to account for the lack of independence between the eyes of an individual, the associations between dietary carbohydrates and risk of cataract in eyes with no or a single type (pure) of cataract were examined. Multivariate adjustment showed that pure cortical cataract (197 eyes) was significantly associated with total carbohydrate intake (odds ratio [OR] comparing the highest quartile with the lowest quartile = 3.19, 95% confidence interval [CI] = 1.10-9.27; P(trend) = 0.017). The OR for nuclear cataract (366 eyes) comparing the third quartile of dGI with the first quartile (OR = 1.64, 95% CI = 1.02-2.65) was significant, but there was not a consistent dose-response association (P(trend) = 0.75). Carbohydrate intake may be optimized to prolong eye lens function. Because of the high proportion of subjects with missing covariates, these results warrant further study.

Role of the Hepatocyte Growth Factor Gene in Refractive Error

Refractive errors such as myopia and hypermetropia are among the leading causes of visual impairment worldwide. Several genetic loci have been associated with myopia but none to date have been reported for hypermetropia. We investigated the hepatocyte growth factor (HGF) as a candidate gene influencing these 2 refractive error states. Case-control study. A total of 551 individuals (193 males, 358 females; mean age, 55.41+/-12.65 years) including 117 individuals with high myopia <or= -6.00 diopters (D), 140 individuals with low/moderate myopia (-2.00 to -5.99 D), 148 emmetropic individuals (-0.50 to +0.75 D) and 146 hyperopic individuals (>+2.00 D) were included in the analysis from 3 different Australian population cohorts (The Genes in Myopia Study, the Blue Mountains Eye Study, and the Melbourne Visual impairment project). Genotyping of 9 tag single nucleotide polymorphisms (SNPs) that encompassed the entire HGF gene and its associated sequences as well as 6 additional SNPs identified through DNA resequencing was undertaken. Genetic association with refraction. After correction for multiple testing, the SNPs rs12536657 (odds ratio [OR], 5.53; 95% confidence interval [CI], 1.14-26.76) and rs5745718 (OR, 2.24; 95% CI, 1.30-3.85) showed significant association with hypermetropia. Whereas the SNPs rs1743 (OR, 2.02; 95% CI, 1.19-3.43; P = .009), rs4732402 (OR, 2.03; 95% CI, 1.23-3.36; P = 0.005), rs12536657 (OR, 2.38; 95% CI, 1.40-4.05; P = 0.001), rs10272030 (OR, 2.22; 95% CI, 1.31-3.75; P = 0.003), and rs9642131 (OR, 2.44; 95% CI, 1.43-4.14; P = 0.001) showed significant association with low/moderate myopia. These findings present the HGF gene as the first gene significantly associated with hypermetropia as well as providing evidence of significant association with myopia in a second ethnic population. In addition, it provides insights into the important biological mechanisms that regulate human ocular development (emmetropization), which are currently poorly understood.

Lutein and Zeaxanthin and the Risk of Cataract: The Melbourne Visual Impairment Project

To evaluate the association of cortical, nuclear, or posterior subcapsular (PSC) cataract with dietary intake of lutein-zeaxanthin (LZ) in a population-based sample. For the study, 3271 (83% of the eligible residents) permanent residents aged > or =40 years were recruited in 1992 to 1994 via a cluster random sampling. In 1997 to 1999, 2594 (79%) attended the follow-up examination including lens photography, a life-style questionnaire, and a food-frequency questionnaire (FFQ). Cases were those with cortical opacity > or =4/16, nuclear opacity grade > or =2.0, or PSC opacity > or =1 mm2. Logistic regression was used to calculate the odds ratios for cataract by daily LZ intake, or its quintile indicator with the lowest quintile as the baseline category, controlling for energy-adjusted fat intake and variables previously found to be associated with the cataract outcomes. Of the 2322 participants who attended the follow-up survey and completed the FFQ, 1841 (79%), 1955 (84%), and 1950 (84%) were included in the analyses of cortical, nuclear, and PSC cataract, respectively. There were 182 (9.9%), 387 (19.8%), and 177 (9.1%) cases for cortical, nuclear, and PSC cataract, respectively. Cortical and PSC cataract were not significantly associated with LZ intake. For nuclear cataract the odds ratios were 0.67 (0.46-0.96) and 0.60 (0.40-0.90) for every 1-mg increase in crude and energy-adjusted daily LZ intake, respectively. The odds ratios (95% CI) for those in the top quintile of crude LZ intake was 0.58 (0.37-0.92; P = 0.023 for trend), and it was 0.64 (0.40-1.03) for energy adjusted LZ intake (P = 0.018 for trend). This study found an inverse association between high dietary LZ intake and prevalence of nuclear cataract.

Rapid and cost‐effective method to assess vision disorders in a population

The aim was to develop a means of rapidly assessing eye health in a cost- and time-effective way to monitor changes over time. Key features of the five main eye diseases that cause vision loss in Australia were assessed. Participation was volunteer-based from randomly selected Melbourne suburbs. Recruitment was by mail. Anterior segments and fundi were photographed with a digital non-mydriatic fundus camera. Visual fields were tested with Frequency Doubling Technology. A questionnaire collected information about demographics, general health and lifestyle. Findings from this rapid assessment were compared with those from a population-based study. A total of 1695 people, aged between 70 and 79 years (mean 74), were recruited. The rates and causes of visual impairment were similar between the rapid assessment method and the population-based study. Among the 134 people (8%) with visual impairment at presentation, 98 (73%) had undercorrected refractive error, 17 (13%) had age-related macular degeneration, 11 (8%) had cataract, 2 (2%) had diabetic retinopathy and 2 (2%) had glaucoma. Screening costs per participant were only about AU$145, compared with AU$433 in the Melbourne Visual Impairment Project (VIP). The application of Frequency Doubling Technology as well as the use of a non-mydriatic digital camera for fundus and lens photography resulted in an average examination time of less than half the time needed in the VIP. Data collection took 3 months rather than 4 years in the VIP. The rapid assessment method was efficient in time and cost and produced results comparable to a normal population-based survey. Repeating the study design for a similarly sampled group every 2 years would allow the assessment of changes in the prevalence of undiagnosed eye disease.

Progression of visual field loss in open angle glaucoma in the Melbourne Visual Impairment Project

To quantify the progression of visual field loss in participants with open angle glaucoma. Cluster random samples of 3271 participants participated in this study. Each participant underwent a standardized ophthalmic examination, which included intraocular pressure measurement, Humphrey 24-2 Fastpac visual field testing and stereophotography of the optic disc. At baseline 118 participants were identified as possible, probable or definite open angle glaucoma and 74 (62.7%) of these were seen again at the follow-up examination. Progression of visual field loss was defined using three methods: the Advanced Glaucoma Intervention Study criteria, the modified Anderson criteria and the Blumenthal method. In total, 49% of subjects showed progressive visual field loss with at least one method. The Blumenthal criteria yielded the highest rate of progression (37%), followed by the modified Anderson method (33%) and the Advanced Glaucoma Intervention Study method (16%). The progressive visual field loss was associated with baseline glaucoma status (P = 0.02); 65% of the definite glaucoma progressed, compared with 57% of the probable glaucoma and 25% of the possible glaucoma. Participants who had been previously diagnosed with glaucoma had a higher rate of progression (54%) when compared with those who had not been diagnosed previously (47%). In total, 50% (four of eight) of those receiving glaucoma medication at baseline had progressive visual field loss; all were in the definite glaucoma category. Despite use of glaucoma medications the majority of glaucoma patients managed by their regular ophthalmologist experienced progressive visual field loss over a 5-year period.

Vision loss in Australia

To assess the prevalence and causes of vision loss in Australia and to project these data into the future. Synthesis of data from two cross-sectional population-based cohort studies--the Melbourne Visual Impairment Project and the Blue Mountains Eye Study--and extrapolation to the entire Australian population. 8376 community and 533 nursing home residents recruited between 1992 and 1996 in urban and rural Victoria and New South Wales. Age-standardised prevalence of low vision (visual acuity < 6/12) and blindness (visual acuity < 6/60) (both measured in the best eye, with spectacles if usually worn for distance vision), and their causes for the Australian population for 2000 to 2024, projected from Australian Bureau of Statistics population data. In 2004, 480,300 Australians were estimated to have low vision, including 50,600 with blindness. The most common causes of low vision were undercorrected refractive error (62%), cataract (14%) and age-related macular degeneration (10%). The latter was responsible for almost half of all cases of blindness. The numbers of people with low vision and blindness are projected to almost double by 2024. Vision loss in Australia is a much bigger problem than is usually recognised; 76% of low vision is caused by uncorrected refractive error or cataract, both readily treatable. However, the prevention and treatment of macular degeneration poses a major challenge.

Utilization of eye care services by Victorians likely to benefit from eye care

To assess the utilization of eye care services by Australians most likely to benefit from eye assessment. The Melbourne Visual Impairment Project was a population-based study that collected demographic, health and vision-related information including use of eye care services. A standardized detailed ophthalmic examination was performed. Utilization of eye care services by those who might most benefit from eye care was assessed and compared to the general population. These participants include those with undiagnosed glaucoma, unoperated visually significant cataract, undercorrected refractive error, diabetes mellitus, age-related macular degeneration and visual acuity < 6/12. Sociodemographic characteristics were assessed for their influence on eye care utilization among these participants. A total of 4744 urban and rural residents participated (86% of those eligible) and 4612 (83% of total eligible) of these had a complete data set for the use of eye care services and were included. There were 933 participants (20.2%) who did not report eye assessment in the previous 5 years, and 891 participants (19.3%) had one or more aforementioned conditions potentially benefiting from eye care. Of these, between 34.4% and 59.4% reported no examination in the previous year and between 9% and 25% reported no examination within the previous 5 years. These participants were more likely to seek eye care within the short term (1 year) if they had a family history of eye disease, otherwise a noticed change in vision was the main influence in the longer term (2-5 years). Male participants, younger participants and those whose main spoken language was not English were less likely to seek eye care in the longer term. In Victoria 19% of those >40 years of age have potentially unmanaged eye disease including glaucoma, unoperated visually significant cataract, undercorrected refractive error, age-related macular degeneration, diabetes mellitus or visual acuity < 6/12. A substantial proportion of these report no eye assessment in the previous 1, 2 or 5 years or ever before. Younger age, male sex and main language other than English make assessment less likely. Many may have these conditions despite having had a recent eye assessment.

Incidence and Progression of Cataract in the Melbourne Visual Impairment Project

Incidence and Progression of Cataract in the Melbourne Visual Impairment Project

Five-year incidence of bilateral cause-specific visual impairment in the Melbourne Visual Impairment Project.

To describe the age-, gender-, and cause-specific 5-year incidence of bilateral visual impairment in participants in the Melbourne Visual Impairment Project, Victoria, Australia. Participants aged 40 years and older were recruited from Melbourne, Victoria, Australia, by random cluster sampling. The mean age of the 3271 (83% of the eligible) participants was 59 +/- 12 (SD) years. Of the participants, 54% were female. The initial baseline study (1992-1994) was followed by a 5-year incidence study (1997-1999). At both time points of the study, participants underwent a standardized testing procedure. Distance and near vision was tested using logarithm of the minimum angle of resolution (logMAR) charts, followed by refraction if needed. Visual fields were assessed by the 24-2 Humphrey field test (FastPac, Humphrey Field Analyzer; Carl Zeiss Meditec, Dublin, CA). Also, intraocular pressure, ocular motility, dilated ophthalmoscopy, and photography of the lens and the fundus were conducted. Furthermore, an interview included demographic characteristics, history of eye disease, medical history, and medication use. For classification of visual impairment, both visual acuity (VA) and visual fields (VF) examination results were used. Four levels of bilateral presenting visual impairment were defined: mild (VA, <20/40-20/60, and/or VF, homonymous hemianopia), moderate (VA, <20/60-20/200, and/or VF, constriction <20 degrees to 10 degrees from fixation), severe (VA, <20/200-10/200, and/or VF, constriction <10 degrees to 5 degrees from fixation), and profound (VA, <10/200, and/or VF, constriction <5 degrees from fixation). For all participants found to be visually impaired, the major cause was identified. Of the 3040 people eligible to attend follow-up 2594 (85%) participated. Data were available for 2530 (98%) participants. In 105 participants (4.22%; 95% confidence limit 2.58-5.85) some degree of visual impairment developed. The main causes were undercorrected refractive error (59%), age-related macular degeneration, cataract and neuro-ophthalmic disorders (7% each), glaucoma (3%), and diabetic retinopathy (1%). The main cause of severe and profound visual impairment was age-related macular degeneration (37%). Undercorrected refractive error was the primary cause of new cases of visual impairment in this population. Further research is needed to understand the origin of this and to develop appropriate prevention measures. Age-related macular degeneration is the primary cause of severe or profound vision loss in Australia. This disease requires further investigation for effective cure and preventive strategies.

Iris colour, ethnic origin and progression of age‐related macular degeneration

To investigate the relationship between iris colour, ethnic origin and the progression of age-related macular degeneration (AMD). Participants were recruited from the population-based Melbourne Visual Impairment Project or the prospective, randomized, double-masked Vitamin E, Cataract and Age-Related Macular Degeneration study. From these two cohorts, 171 participants aged between 52 and 93 years who were identified as having early AMD features at their baseline examination (1992-1995) were followed for an average of 6.8 years (until 2001) to determine the progression rate of early AMD. The participants' iris colour was categorized as light, intermediate or dark. Ethnic origin was categorized as Anglo-Saxon or non-Anglo-Saxon, according to the participants' grandparents' country of birth. In total, 53 (31%) of the 171 participants showed signs of AMD progression. Participants with light iris colour had twofold the risk of AMD progression of those with dark or intermediate iris colours, although the age-adjusted and multivariate-adjusted associations were not significant (both P = 0.13). Age-adjusted and multivariate comparisons of Anglo-Saxon ethnic origin to non-Anglo-Saxon ethnic origin showed a noticeable but non-significant association with progression of AMD (P= 0.22 and P= 0.14, respectively). Individuals with light iris colour or of Anglo-Saxon ethnic origin had a strong tendency to greater progression of AMD. A larger sample is required to confirm these clinically important, but statistically non-significant, associations.

Five‐year incidence of diabetic retinopathy in the Melbourne Visual Impairment Project

The purpose of the present paper was to describe the 5-year incidence and progression of diabetic retinopathy in the Melbourne Visual Impairment Project (VIP) cohort. Baseline examinations were conducted from 1992 to 1994 and follow-up data were collected 5 years later. Data collected during the baseline and follow-up studies included medical history (including previous diagnosis of diabetes mellitus) and dilated fundus examination. Two 30 degrees stereoscopic fundus photographs were taken with a Topcon TRC fundus camera, one centred on the optic disc and the other centred on the fovea. Photographs from participants who reported having diabetes were graded for diabetic retinopathy based on an extension of the Modified Airlie House Classification. Grouping of participant data into retinopathy grades was based on the results of the worst eye. The follow-up survey included 82% (n = 121) of those with diabetes at baseline. Prevalence of any retinopathy was 35.7% and macular oedema was 13% at follow up. Diabetic retinopathy was newly detected in 8/73 (5-year incidence = 11.0%, 95% confidence interval (CI) = 3.8-18.1). Disease progression was seen in 9/31 participants (29.0%, 95%CI = 14.9-47.8) who had diabetic retinopathy at baseline. The 5-year incidence of proliferative diabetic retinopathy in people without proliferative diabetic retinopathy at baseline was 2.9% (3/104, 95%CI = 0-6.4). The 5-year incidence of macular oedema in people who did not have macular oedema at baseline was 8.0% (8/100, 95%CI = 2.7-13.3). All people with proliferative diabetic retinopathy at baseline had received laser treatment by the follow-up survey. Twenty-four per cent of people without diabetic retinopathy reported never having had a dilated fundus examination (excluding the VIP examinations). The 5-year incidence of diabetic retinopathy was 11% in the Melbourne Visual Impairment Project. Most people with proliferative diabetic retinopathy or macular oedema are receiving treatment. However, many people with diabetes are not having regular dilated fundus examinations.

Incidence and progression of cataract in the Melbourne Visual Impairment Project

PurposeTo determine the 5-year incidence and progression of cataract and cataract surgery in the Melbourne Visual Impairment Project. DesignProspective cohort study. MethodsDemographic information including race, sex, age, and education level was collected at baseline. Cortical cataract was defined as 4/16 or greater opacity; progression was defined as a more than 2/16 increase. Nuclear cataract was defined as Wilmer standard grade 2 or higher; progression was defined as more than 0.5 increase. Posterior subcapsular (PSC) cataract was defined as opacity 1 mm2 or greater; progression was defined as greater than 1 mm2 increase. ResultsOf the 3,040 participants eligible to attend follow-up examinations, 2,594 (85% of those eligible) participated. The mean age of participants at follow-up was 62.5 years, and 55% were female. The percentage of patients who had at least one lens extracted over 5 years increased from 0.5% of those aged 40 to 49 years at baseline to 35.7% of those aged 80 years or more at baseline. The overall incidence of the three types of cataract was as follows: cortical 7.7% (95% confidence limits [CL] = 5.8–9.8), nuclear 16.4% (95% CL = 12.1–20.8), and PSC 7% (95% CL = 5.3–8.7). The overall progression of cataract was cortical 14.3% (95% CL = 10.2–18.3), nuclear 19.3% (95% CL = 15.9–22.7), and PSC 20% (95% CL = 8.7–31.1). The incidence and progression rates increased significantly by age, but the rates were not significantly different by sex. ConclusionsThese cataract incidence data confirm the public health importance of cataract in Australia. The data also support the need to plan both primary prevention program and adequate surgical services to meet the anticipated increase in demand with the aging population.

Projected prevalence of age-related cataract and cataract surgery in Australia for the years 2001 and 2021: pooled data from two population-based surveys.

This study aimed to estimate the number of Australians over 50 with cataract in the years 2001 and 2021. Data from two population-based studies were pooled: the Blue Mountains Eye Study and Melbourne Visual Impairment Project and Australian Bureau of Statistics population projections were used. Similar definitions for the three cataract types were used in the two studies (nuclear >/= grade 4, posterior sub-capsular >/= 1 mm, cortical >/= 10% lens area or >/= 25% circumference). Combining the three types and prior surgery, it was estimated that in 2001, 1.7 million Australians had clinically significant cataract in either eye and 320,000 had previously undergone cataract surgery. It was estimated that the number of persons with cataract will rise to 2.7 million by 2021 (over 500,000 will have had cataract surgery). The number of Australians with cataract will grow by two-thirds during the next 20 years, reflecting continued population ageing. Health care delivery systems will need to develop methods to handle this increased workload.

The Risks of Everyday Life: Predictors of falls in the Melbourne Visual Impairment Project

To assess factors associated with falls in the past month, including visual acuity and other vision-related variables. A household census was used to recruit permanent residents aged 40 years and older for baseline examinations of the Melbourne Visual Impairment Project conducted from 1992-94. At the five-year follow-up examinations, returning participants were asked to recall all falls that they had ever experienced and also how many falls they had experienced in the past month. Falls history was divided into those that occurred at home and away from home. Standardised examination of visual acuity was performed. Of the original cohort of 3,271, 231 (7.1%) were reported to have died, leaving 3,040 eligible. Of these, 2,594 (85%) were examined, 51 (2%) had moved interstate or overseas, 83 (3%) could not be traced, and 312 (10%) refused to participate. A history of having ever fallen at home was reported by 466 (20%) participants, and 406 (17.3%) reported having fallen away from home at least once. Five per cent of the cohort (129/2,343) had fallen in the previous month. Factors significantly related to falls at home in the past month in a multivariate logistic regression model included age (OR=1.56 for 10-year age groups) and nuclear cataract (OR=2.87). Irrespective of visual acuity, cataract is major risk factor for falls at home. Interventions aimed at decreasing the incidence of falls in the community should include assessment of both visual acuity and cataract status and referral for treatment if functional impairment is evident.

Cataract in the 21st Century: lessons from previous epidemiologic research

Background: Cataract surgery is currently the most commonly performed ophthalmic procedure in Australia. The purpose of this paper is to review Australian data on cataract prevalence and risk factors and to project potential future demand for cataract services.Methods: Age‐ and gender‐specific cataract prevalence data from the Melbourne Visual Impairment Project (VIP) and the Blue Mountains Eye Study (BMES) were applied to population estimates from the Australian Bureau of Statistics. Published cataract risk factor data from the two studies were reviewed.Results: Although the projected number of cataracts varies substantially based on the definition used, the relative number of cataracts will double over the next 50 years due to the aging of the population. Risk factors for cortical cataract identified in both the VIP and the BMES included female gender, sunlight exposure and myopia. Concord‐ ant findings for nuclear cataract included female gender, brown irides, cigarette smoking and myopia. The only risk factor for posterior subcapsular cataract (PSC) that was identified in both studies was myopia. Some of the discrepant findings between the two studies included alcohol intake, diabetes and medication use.Discussion: These data suggest that supply and demand for cataract surgery must be considered and managed to maintain the current level of cataract surgery delivery as the number of people with cataract increases at a proportionately greater rate than the total population. The supply of cataract surgical services could be increased through an increase in the number of ophthalmologists, an increase in the efficiency with which cataract surgical services are delivered, or improved technology. The demand for cataract surgery could be decreased through the implementation of effective primary prevention strategies, although successful strategies are currently unknown and/or untested. Given our current state of knowledge about cataract, it seems most feasible immediately to alter the health service delivery side of the equation to reduce the public health burden of cataract.

Vision impairment predicts 5 year mortality

AIMTo describe predictors of mortality in the 5 year follow up of the Melbourne Visual Impairment Project (VIP) cohort.METHODSThe Melbourne VIP was a population based study of the distribution and...

Projected number of Australians with glaucoma in 2000 and 2030.

Accurate Australian glaucoma prevalence has been provided by two population-based studies: the Blue Mountains Eye Study (BMES) and the Melbourne Visual Impairment Project (MVIP). Both stud es defined glaucoma as the presence of matching optic disc cupp ng with rim thinning and g aucomatous field defects demonstrated on automated perimetry Combining 'definite' and 'probable' rates, the glaucoma prevalence in persons aged 50 and over, age-standardized for the 2000 projected Australian population, was 2.70% (BMES) and 3.13% (MVIP), including rates for 'definite' glaucoma of 2.12% (BMES) and 2.50% (MVIP). The number of Australians aged 50 and over in the year 2000 with g aucoma could be estimated as from 144 000 persons (BMES) to 167 000 persons (MVIP). Assuming similar age-specific rates, the number of Austral ans aged 50 and over in the year 2030 wth glaucoma could be estimated as from 307 000 persons (BMES) to 337 000 persons (MVIP). Ocular hypertens on (OH) was defined as present in subjects without glaucoma wth intraocular pressure (IOP) of more than 21 mmHg, including treated subjects with 'normal' examination IOP The age-standardized OH prevalence was 5.15% (BMES), which projects to 275000 Australians with OH in 2000, increasing to 513000 in 2030.