Vision impairment predicts 5 year mortality.

AIM: To describe predictors of mortality in the 5 year follow up of the Melbourne Visual Impairment Project (VIP) cohort. METHODS: The Melbourne VIP was a population based study of the distribution and determinants of age related eye disease in a cluster random sample of Melbourne residents aged 40 years and older. Baseline examinations were conducted between 1992 and 1994. In 1997, 5 year follow up examinations of the original cohort commenced. Causes of death were obtained from the National Death Index for all reported deaths. RESULTS: Of the original 3271 participants, 231 (7.1%) were reported to have died in the intervening 5 years. Of the remaining 3040 participants eligible to return for follow up examinations, 2594 (85% of eligible) did participate, 51 (2%) had moved interstate or overseas, 83 (3%) could not be traced, and 312 (10%) refused to participate. Best corrected visual acuity <6/12 (OR=2.34) was associated with a significantly increased risk of mortality, as were increasing age (OR=1.09), male sex (OR=1.62), increased duration of cigarette smoking (OR=2.06 for smoking >30 years), increased duration of hypertension (OR=1.51 for duration >10 years), and arthritis (OR=1.42). CONCLUSIONS: Even mild visual impairment increases the risk of death more than twofold. Further research is needed to determine why decreased visual acuity is associated with increased risk of mortality.

Attributable risk estimates for cataract to prioritize medical and public health action.

PURPOSE: Cataract is the most common cause of blindness in the world. The purpose of this study was to estimate the population attributable risk associated with identified risk factors for cortical, nuclear, and posterior subcapsular (PSC) cataract in a representative sample of the Victorian population aged 40 years and older. METHODS: Cluster, stratified sampling was used and participants were recruited through a household census. At locally established test sites, standardized clinical examinations were performed to assess cataract and personal interviews were conducted to quantify potential risk factors. Multivariate logistic regression was used to determine the independent risk factors associated with the three types of cataract, and the population attributable risk was calculated. RESULTS: A total of 3271 (83% of eligible) of the urban residents and 1473 (92%) rural residents participated. The urban residents ranged in age from 40 to 98 years (mean, 59 years), and 1511 (46%) were men. The rural residents ranged in age from 40 to 103 years (mean, 60 years), and 701 (48%) were men. The overall prevalence of cortical cataract was 12.1% (95% CL 10.5, 13.8), nuclear cataract 12.6% (95% CL 9.61, 15.7), and PSC cataract 4.93% (95% CL 3.68, 6.17). Significant risk factors for cortical cataract included age, female gender, diabetes for greater than 5 years, gout for greater than 20 years, arthritis, myopia, average annual ocular UV-B exposure, and family history of cataract (parents or siblings). Significant risk factors for nuclear cataract included age, female gender, rural residence, age-related maculopathy, diabetes for greater than 5 years, smoker for greater than 30 years, and myopia. The significant risk factors for PSC cataract were age, rural residence, thiazide diuretic use, and myopia. Of the modifiable risk factors, ocular UV-B exposure explains 10% of the cortical cataract in the community, and cigarette smoking accounts for 17% of the nuclear cataract. CONCLUSIONS: Because of the near universal exposure to UV-B in the environment, ocular protection has one of the highest modifiable attributable risks for cortical cataract and would therefore be an ideal target for public health intervention. Quit smoking campaigns can be expanded to incorporate information about the excess cataract in the community associated with long-term smoking. Nonmodifiable risk factors such as age, gender, and long-term medication use have implications for the timely referral and treatment for those at higher risk of cataract.

Association of presbyopic correction with changes in visual fields.

The purpose of this study was to investigate the effect of presbyopic correction on changes in visual fields caused by an alteration in outflow of aqueous humour Visual fields were compared before and after introduction of presbyopic correction in participants of the Melbourne Visual Impairment Project. Height and slope of the 'Hill of Vision' were assessed by calculating median thresholds in the four sets of three eccentric points. Analysis of 101 eyes in the study group and 101 eyes in the control group shows higher decrease of the 'Hill of Vision' height in the group of participants who started wearing presbyopic correction, than in the group without presbyopic correction (P = 0.02). Intraocular pressure measured irrespectively of participant's accommodative activity was not significantly different between the two groups at both time points. These data suggest that the use of presbyopic correction is associated with changes in the visual field.

Operated and unoperated cataract in Australia.

PURPOSE: To quantify the prevalence of cataract, the outcomes of cataract surgery and the factors related to unoperated cataract in Australia. METHODS: Participants were recruited from the Visual Impairment Project: a cluster, stratified sample of more than 5,000 Victorians aged 40 years and over. At examination sites interviews, clinical examinations and lens photography were performed. Cataract was defined in participants who had: had previous cataract surgery, cortical cataract greater than 4/16, nuclear greater than Wilmer standard 2, or posterior subcapsular greater than 1 mm2. RESULTS: The participant group comprised 3,271 Melbourne residents, 403 Melbourne nursing home residents and 1,473 rural residents. The weighted rate of any cataract in Victoria was 21.5%. The overall weighted rate of prior cataract surgery was 3.79%. Two hundred and forty-nine eyes had had prior cataract surgery. Of these 249 procedures, 49 (20%) were aphakic, 6 (2.4%) had anterior chamber intraocular lenses and 194 (78%) had posterior chamber intraocular lenses. Two hundred and eleven of these operated eyes (85%) had best-corrected visual acuity of 6/12 or better, the legal requirement for a driver's license. Twenty-seven (11%) had visual acuity of less than 6/18 (moderate vision impairment). Complications of cataract surgery caused reduced vision in four of the 27 eyes (15%), or 1.9% of operated eyes. Three of these four eyes had undergone intracapsular cataract extraction and the fourth eye had an opaque posterior capsule. No one had bilateral vision impairment as a result of cataract surgery. Surprisingly, no particular demographic factors (such as age, gender, rural residence, occupation, employment status, health insurance status, ethnicity) were related to the presence of unoperated cataract. CONCLUSIONS: Although the overall prevalence of cataract is quite high, no particular subgroup is systematically underserviced in terms of cataract surgery. Overall, the results of cataract surgery are very good, with the majority of eyes achieving driving vision following cataract extraction.

The prevalence of age-related maculopathy: the visual impairment project.

PURPOSE: To determine the prevalence of age-related maculopathy (ARM) lesions in residents of the state of Victoria, Australia. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Total of 5147 residential and institutionalized persons aged 40 years and older, living in Victoria. METHODS: Participants were recruited through a cluster, stratified, random sampling from nine urban clusters and four rural clusters. The presence of ARM lesions was graded from color stereo fundus photographs as well as slit-lamp stereo biomicroscopy according to the International Classification and Grading System. MAIN OUTCOME MEASURES: The presence of ARM lesions. RESULTS: The mean age of participants was 60.2 years, and 55% were females. Gradable fundus photographs were available for at least one eye in 4345 (92%) of the participants. The weighted prevalence of neovascular age-related macular degeneration (AMD) was 0.39% (95% confidence limits [CL] = 0.20, 0.58), atrophic AMD was 0. 27% (95% CL = 0.04, 0.50), and total AMD was 0.68% (95% CL = 0.30, 1. 1). Prevalence of AMD was strongly related to age (P < 0.001). Prevalence of early ARM was 15.1% (95% CL = 13.7, 16.4). Large drusen, 125 micrometer or more, were present in 6.3% of the participants. There was a higher prevalence of soft distinct drusen (7.5%) than soft indistinct drusen (4.3%). Retinal pigmentary abnormalities were present in 8.2% (95% CL = 7.2, 9.2). The prevalence of large drusen, soft drusen, and pigmentary abnormalities increased with age (P < 0. 001). Prevalence of retinal pigmentary abnormalities increased with increasing drusen size (P < 0.001). Soft indistinct drusen were more common in women aged 70 years or older (P < 0.001). Bilaterality of any ARM was strongly age related, and women appeared to have a higher risk of both bilateral early ARM and AMD. CONCLUSIONS: These data provide age- and gender-specific prevalence of ARM and its component lesions in an ethnically diverse Australian population. Early ARM and AMD prevalence rates increased sharply from ages 70 and 80 years, respectively, in all ethnic groups. These higher rates will continue to increase the importance of AMD as our population ages.

Vision impairment predicts five-year mortality.

PURPOSE: To describe predictors of mortality in the 5-year follow-up of the Melbourne Visual Impairment Project (VIP) cohort. METHODS: The Melbourne VIP was a population-based study of the distribution and determinants of age-related eye disease in a cluster random sample of Melbourne residents aged 40 years and older. Baseline examinations were conducted between 1992 and 1994. In 1997, 5-year follow-up examinations of the original cohort commenced. Causes of death were obtained from the National Death Index for all reported deaths. RESULTS: Of the original 3,271 participants, 231 (7.1%) were reported to have died in the intervening 5 years. Of the remaining 3,040 participants eligible to return for follow-up examinations, 2,594 (85% of eligible) did participate, 51 (2%) had moved interstate or overseas, 83 (3%) could not be traced, and 312 (10%) refused to participate. Best corrected visual acuity < 6/12 and cortical cataract were associated with a significantly increased risk of mortality, as were increasing age, male sex, increased duration of cigarette smoking, increased duration of hypertension, and arthritis. CONCLUSIONS: Even mild visual impairment increases the risk of death more than twofold.