Cataract, Visual Impairment and Long-Term Mortality in a Rural Cohort in India: The Andhra Pradesh Eye Disease Study

A large-scale prevalence survey of blindness and visual impairment (The Andhra Pradesh Eye Diseases Study [APEDS1]) was conducted between 1996-2000 on 10,293 individuals of all ages in three rural and one urban clusters in Andhra Pradesh, Southern India. More than a decade later (June 2009-March 2010), APEDS1 participants in rural clusters were traced (termed APEDS2) to determine ocular risk factors for mortality in this longitudinal cohort.  Mortality hazard ratio (HR) analysis was performed for those aged >30 years at APEDS1, using Cox proportional hazard regression models to identify associations between ocular exposures and risk of mortality. Blindness and visual impairment (VI) were defined using Indian definitions. 799/4,188 (19.1%) participants had died and 308 (7.3%) had migrated. Mortality was higher in males than females (p<0.001). In multivariable analysis, after adjusting for age, gender, diabetes, hypertension, body mass index, smoking and education status the mortality HR was 1.9 (95% CI: 1.5-2.5) for blindness; 1.4 (95% CI: 1.2-1.7) for VI; 1.8 (95% CI: 1.4-2.3) for pure nuclear cataract, 1.5 (95% CI: 1.1-2.1) for pure cortical cataract; 1.96 (95% CI: 1.6-2.4) for mixed cataract, 2.0 (95% CI: 1.4-2.9) for history of cataract surgery, and 1.58 (95% CI: 1.3-1.9) for any cataract. When all these factors were included in the model, the HRs were attenuated, being 1.5 (95% CI: 1.1-2.0) for blindness and 1.2 (95% CI: 0.9-1.5) for VI. For lens type, the HRs were as follows: pure nuclear cataract, 1.6 (95% CI: 1.3-2.1); pure cortical cataract, 1.5 (95% CI: 1.1-2.1); mixed cataract, 1.8 (95% CI: 1.4-2.2), and history of previous cataract surgery, 1.8 (95% CI: 1.3-2.6).  All types of cataract, history of cataract surgery and VI had an increased risk of mortality that further suggests that these could be potential markers of ageing.

Related papers:

title: Visual acuity and mortality in a chinese population. The Tanjong Pagar Study.
abstract: To examine the relationship between visual acuity and mortality in a Chinese population.



Population-based cohort study.



Chinese persons in Singapore ages 40 to 79 years at baseline examination.



The Tanjong Pagar Study in Singapore examined 1232 persons (response rate, 71.8%) at the baseline examination in 1997 and 1998. Participants had measurements of presenting and best-corrected visual acuity (VA) using standardized protocols. Mortality data were obtained from the National Death Registry, which linked subjects who had died since the baseline examination. Cause of death was determined from the International Classification of Diseases 9 codes. Analysis was performed on 1225 (99.4%) participants with VA data.



All-cause mortality.



By December 31, 2004 (median follow-up, 6.8 years), 126 persons had died. Participants with presenting VA in the better eye worse than 20/40 (logarithm of the minimum angle of resolution [logMAR] score, 0.3) had a significantly higher mortality rate (hazard ratio [HR], 2.9; 95% confidence interval [CI], 1.4-6.3, adjusting for age, gender, hypertension, diabetes, smoking, heart attack, stroke, and income) as compared with participants with VA of 20/20 (logMAR, 0.0). Associations were similar for best-corrected VA in the better eye (HR, 2.7; 95% CI, 1.4-5.5). Among clinic participants with logMAR VA measurements, each 1-line difference in presenting VA (logMAR gain, 0.10) was associated with a 4-fold increased risk of mortality (HR, 4.4; 95% CI, 1.9-10.2).



In this Chinese population in Singapore, visual impairment was associated independently with an increased risk of mortality.

title: Age-related eye disease and survival. The Beaver Dam Eye Study.
abstract: To investigate the relationship of cataract, age-related maculopathy, glaucoma, and visual impairment to survival in the population-based Beaver Dam Eye Study.



In this population-based study, visual acuity was measured with use of standardized protocols. At baseline, stereoscopic color fundus photographs and color slit-lamp and retroillumination photographs were graded in a masked fashion to determine the presence of age-related maculopathy and cataract, respectively. Deaths were ascertained by contacting family members, daily review of obituaries, and use of vital status records.



Subjects aged 43 through 84 years who lived in Beaver Dam, Wis, were identified and examined between 1988 and 1990.



From the time of the baseline examination until a median of 4 years later, 9.5% (467/4926) of the population had died. After correcting for age and sex, poorer survival was associated with more severe nuclear sclerosis (5-year survival of 88.9% for the most severe compared with 94.1% for the least severe stage) and visual impairment (5-year survival of 87.5% for impaired compared with 91.8% for unimpaired vision). However, after controlling for systemic factors, only more severe nuclear sclerosis in people without diabetes was significantly associated with poorer survival (hazard ratio per level of severity, 1.19; 95% confidence interval, 1.00 to 1.40).



These data suggest that after controlling for age and sex, nuclear sclerotic cataract severity, cataract surgery, and visual impairment are risk indicators for poorer survival. Cortical cataract, posterior subcapsular cataract, glaucoma, and age-related maculopathy were unrelated to poorer survival.

title: Visual Impairment and Mortality in a Rural Adult Population (The Southern Harbin Eye Study)
abstract: To evaluate the association between visual acuity (VA) and 4-year mortality in an older population-based cohort.  Five thousand and fifty-seven persons aged 50 to 96 years (91.0% of the eligible population) residents of the Southern Harbin, Heilongjiang Provence, China participated in the study. At baseline (2006), the main ocular diseases were diagnosed from a basic ocular examination including presenting and best-corrected VA. Of the 5,057 participants in the baseline survey, those who died after the study were identified and the death certificate was checked. The physicians in charge of the health of the village population were asked for the presumed cause of death. The rate of death was determined in the follow-up survey in 2010. We evaluated the association of visual impairment (VI) and mortality using multiple logistic regression.  Between the baseline examination and the censoring cutpoint study, a total of 214 subjects (4.2%) were dead. Females with VI were less likely to have died relative to male gender with VI (P < 0.05). Compared with participants who reported better presenting VA (VA ≥ 20/60), the risk of mortality was significantly higher for those reporting moderate VI (20/400 ≤ VA < 20/60) (Odds Ratio [OR], 2.1; 95% confidence interval [CI],1–4.1) and those reporting severe VI (VA < 20/400) (OR,3.6; 95% CI, 2.0–6.6). Similar associations were obtained for best-corrected VA in the better eye (OR, 3.1; 95% CI: 1.5–6.4 and 3.9; 95%CI: 2.1–7.2, respectively).  In this Chinese population-based cohort we found that visual impairment predicted a significantly elevated mortality.

title: Vision impairment predicts 5 year mortality
abstract: To describe predictors of mortality in the 5 year follow up of the Melbourne Visual Impairment Project (VIP) cohort.  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.  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).  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.

title: Increase in mortality associated with blindness in rural Africa.
abstract: Forty-seven persons were identified with visual impairment (visual acuity of 6/60 or less in their better eye) during a population-based survey in 1986 of eye disease in three villages in central Tanzania. Four years later, 41 (87%) of them and 70 (82%) of 84 age-, sex-, and village-matched controls with normal functional vision (visual acuity 6/18 or better in the better eye) were traced, and those who were still alive were re-examined. The remainder were reported to be alive but had moved to other villages. Deaths among those aged 40-79 years amounted to 10 among the 37 visually impaired and 7 among the 70 sighted controls. This gave an excess mortality rate (odds ratio) of 3.33 times (1.03-11.04, 95% Cl) among the visually impaired compared to their age-matched controls. The excess mortality rate for visually impaired women was 4.11 (0.72-25.5) and 2.71 (0.50-15.2) for visually impaired men. Nine out of 25 with vision of less than 3/60 in their better eye had died. The higher mortality rate among the visually impaired suggests that, in this environment, blindness is not only associated with considerable disability but is also associated with a shortened life expectancy, especially for women.

title: Cause-specific visual impairment and mortality: results from a population-based study of older people in the United Kingdom.
abstract: To assess the association between mortality and cause-specific visual impairment in older people.



Visual acuity and causes of visual impairment were collected in 13 569 participants 75 years and older participating in a randomized trial of health screening. Participants were followed up for mortality for a median of 6.1 years.



Compared with those with 6/6 (or 20/20 Snellen) or better visual acuity, the age- and sex-adjusted rate ratio for visually impaired people (binocular visual acuity <6/18 or <20/60 Snellen) was 1.60 (95% confidence interval, 1.47-1.74), which was markedly attenuated (rate ratio, 1.17; 95% confidence interval, 1.07-1.27) after adjustment for confounding factors. People whose visual impairment was due to cataract or age-related macular degeneration had excess risks of all-cause and cardiovascular mortality, which disappeared after adjustment. People with refractive error remained at small risk, despite adjustment, probably owing to residual confounding from factors associated with minimal use of eye services rather than underlying eye disease. There were no associations with cancer mortality.



Associations reported for visual impairment and mortality or for specific causes of visual impairment reflect confounding by comorbidities, risk factors, and other factors related to susceptibility to death rather than an independent biological association of vision problems or specific eye diseases.

title: Visual impairment, age-related cataract, and mortality.
abstract: To explore associations between visual impairment, cataract, and mortality in older persons after adjusting for other factors associated with mortality.



A population cohort of 3654 persons aged 49 years or older (82.4% of eligible residents in the Blue Mountains region, west of Sydney, Australia), were examined at the Blue Mountains Eye Study baseline period (1992-1994) and followed up 5 years later (1997-1999). Australian National Death Index data were used to confirm persons who had died since baseline. Associations between mortality and presence of visual impairment and cataract at baseline were assessed using the Cox proportional hazards regression model, controlling for age, sex, demographic and socioeconomic status, medical history, and health risk behaviors.



By June 30, 1999, 604 participants (16.5%) had died. The age- and sex-standardized 7-year cumulative mortality rate was 26% among persons with any visual impairment and 16% in persons without visual impairment. After adjusting for factors found significantly associated with mortality, including age, male sex, low self-rated health, low socioeconomic status, systemic medical conditions, and negative health risk behaviors, the presence at baseline of any visual impairment was independently associated with increased mortality risk (risk ratio [RR], 1.7; 95% confidence interval, 1.2-2.3). The presence of age-related cataract, either nuclear (RR, 1.5), cortical (RR, 1.3), or posterior subcapsular cataract (RR, 1.5), was also significantly associated with increased mortality risk. These associations remained statistically significant when visual impairment and each type of cataract were included simultaneously in the multivariate Cox model.



Visual impairment and age-related cataract may be independent risk factors for increased mortality in older persons.

title: Mortality and ocular diseases: the Beijing Eye Study.
abstract: To examine the relationship between mortality and major ocular diseases.



Population-based study.



At baseline in 2001, the Beijing Eye Study examined 4439 subjects with an age of 40 years or more. The mean age was 56.2+/-10.6 years (range, 40-101 years). In 2006, all study participants were invited for a follow-up examination.



The participants underwent a detailed ophthalmic examination and answered questions regarding their socioeconomic background. Rate of mortality was determined in the follow-up survey of 2006.



Factors associated with mortality.



Of the 4439 subjects examined in the 2001, 3251 (73.2%) subjects returned for the follow-up examination, whereas 143 (3.2%) subjects had died and 1045 (23.5%) subjects were alive but did not agree to be reexamined. In binary logistic regression analysis, mortality was significantly associated with the systemic parameters of higher age (P<0.001; odds ratio [OR], 1.07), male gender (P = 0.01; OR, 0.55), lower level of education (P<0.001; OR, 0.65), smoking status (P = 0.023; OR, 1.25), and with the ocular parameters of level of diabetic-like retinopathy (P = 0.036; OR, 1.02), presence of angle-closure glaucoma (P = 0.013; OR, 3.74), and presence of nonglaucomatous optic nerve damage (P = 0.027; OR, 3.41). Presence of retinal vein occlusions was associated marginally with mortality (P = 0.059; OR, 2.59). Mortality was not significantly associated with best-corrected visual acuity (P = 0.14) in multivariate analysis, nor with age-related macular degeneration, open-angle glaucoma, trachoma, any type of cataract, visual field defects, intraocular pressure, or refractive error.



If socioeconomic parameters, age, gender, and smoking status were taken into account, ocular parameters associated with an increased mortality were diabetic-like retinopathy, angle-closure glaucoma, and nonglaucomatous optic nerve damage. Retinal vein occlusions were marginally associated. Other major ocular disorders such as any form of cataract, open-angle glaucoma, age-related macular degeneration, trachoma, pterygia, and high myopia or high hyperopia were not significantly related to mortality.

title: Lens opacities and mortality : the Barbados Eye Studies.
abstract: To evaluate the association between cataract and mortality in a black population by type of opacity, which has not been documented previously.



Population-based cohort study.



The Barbados Incidence Study of Eye Diseases reexamined the Barbados Eye Study cohort, identified through a simple random sample of predominantly black Barbadian-born citizens, aged 40 to 84 years. Of those eligible, 85% (3427 participants) had a 4-year follow-up visit.



Baseline and follow-up visits included an interview, blood pressure and other measurements, and a detailed ophthalmologic examination with slit-lamp lens gradings (Lens Opacities Classification System [LOCS] II protocol). Mortality at follow-up was verified from Ministry of Health records.



Lens opacities were defined by a LOCS II score of 2 or more. Opacity types were classified in two ways: (1) single (cortical-only, nuclear-only, and posterior subcapsular-only) and mixed opacities; and (2) any cortical, any nuclear, or any posterior subcapsular opacities. Information on dates and causes of death was obtained from death certificates.



Cardiovascular disease was the principal cause of death in black participants (3.6%), followed by malignant neoplasms (1.4%). The cumulative 4-year mortality varied with lens types, increasing from 3.2% for those without cataract to 6.0% for cortical-only, 8.8% for nuclear-only, and 20.9% for mixed opacities. Persons with mixed opacities had a 1.6-fold increase in mortality, while controlling for other factors (age, male gender, diabetes, hypertension, obesity, cigarette smoking, cardiovascular disease, and family history of diabetes) in Cox proportional-hazards regression analyses. Persons with any nuclear opacities also had increased mortality (death rate ratio, 1.5). The death rate ratios increased with age, but peaked at age 60 to 69 years. Coexisting diabetes further increased mortality: people with mixed opacities and diabetes had a 2.7-fold increased risk of death. A trend toward increased mortality from neoplasms was observed for individuals with mixed opacities or with any nuclear opacities.



Participants with mixed opacities or any nuclear opacities had increased 4-year mortality rates, with diabetes acting as an effect modifier. This study is the first to identify a relationship between type of cataract and mortality in an African-descent population.

title: Association between lens opacities and mortality in the Priverno Eye Study
abstract: BackgroundLens opacities are associated with a higher risk of death, although there are some discrepancies regarding the specific types of cataract representing risk. The purpose of the present study was to further investigate the relationships between different types of lens opacity and patient survival.MethodsIn 1987, 860 residents of Priverno, Italy, aged 45–69 years underwent an ophthalmologic examination. Based on patient histories and the findings of the slit-lamp examination, each of the 860 patients was classified according to the type of opacity (pure cortical, pure nuclear, pure posterior subcapsular, mixed, and surgical aphakia). The survivors of the original cohort were re-examined in 1994. Death and survival rates were computed by the Kaplan–Meier method. Associations between mortality and significant factors were included in a stepwise Cox proportional-hazards regression model.ResultsForty-four members of the original cohort had died during the 7-year follow-up. Age-adjusted survival curves based on Kaplan–Meier estimates showed significantly lower survival in those whose baseline examinations had revealed pure nuclear opacity (log rank test: P=0.020) and aphakia (log rank test: P<0.001). When adjusted for other mortality risk factors (age, sex, diabetes, cardiovascular diseases), the hazard ratio was 4.32 for pure nuclear opacity (95% CI 1.13–16.4) and 18.3 for aphakia (95% CI 3.21–104.0).ConclusionsThe analysis of the Priverno data seems to confirm an association between lower survival and cataracts, particularly those confined to the lens nucleus and those that had already prompted surgery.

title: Lens changes and survival in a population-based study.
abstract: The Framingham Heart Study was begun in 1948 to study factors associated with cardiovascular disease. Participants have been reexamined approximately every two years. From 1973 to 1975, the Framingham Eye Study examined the eyes of available Heart Study participants. We used information about nearly 2000 persons from these population-based studies to investigate the relation of lens changes to survival. Follow-up ranged from five to eight years; 312 persons (16 per cent) died. Proportional-hazards regression analyses indicated an overall association of lens changes and decreased survival (P = 0.01), but detailed investigation showed (1) no association of lens changes and decreased survival among persons without diabetes (P = 0.29) and (2) a significant association of lens changes and decreased survival among persons with diabetes (P = 0.001). Diabetic persons with lens changes had an estimated death rate more than twice that of diabetics without lens changes. The duration of diabetes and degree of retinopathy were not associated with survival in this group, most of whom had adult-onset diabetes of short duration. We conclude that lens changes are earlier predictors of death in diabetics than these more traditional variables.

title: Increased mortality in women with cataract: a population based follow up of the North London Eye Study
abstract: In diabetics, cataract is associated with higher risk of death. In non-diabetics the data are conflicting, but some indicate an association between one type of cataract (nuclear) and increased mortality. The aim of this study was to estimate and compare age and sex specific mortality for elderly people with and without cataract in a population based cohort.  A random sample drawn from a defined population of elderly people (age 65 and older) registered with 17 general practice groups in north London formed the study cohort and were followed up for 4 years. The age and sex specific mortality from various causes was estimated and compared in those with and without cataract.  In non-diabetics (n=1318), cataract (lens opacity at baseline) was significantly associated with higher mortality in women. The age standardised death rate per 1000 was 39.8 and 24.8 in women with and without cataract, respectively (age adjusted hazard ratio 1.7, confidence limits 1.1 to 2.7, p=0.032). This was not the case in non-diabetic men (hazard ratio 0.9, confidence limits 0.6 to 1.5, p=0.782). The excess mortality in women with cataract was consistent for cardiovascular, respiratory, and other non-cancer causes of death. There was no association between cataract and mortality from cancer.  This study has shown, for the first time, that cataract is associated with higher mortality in women but not in men, among the non-diabetic population. This sex effect suggests that women may be exposed to risk factors that increase both the risk of cataract and mortality, and that men may have little or no exposure to these “sex specific” factors. Possible risk factors that warrant further investigation may be those associated with some pregnancy and childbearing experience.

title: Mixed lens opacities and subsequent mortality.
abstract: Previous studies have found an association between cataract or lens opacity and increased risk of mortality. Further work on determining explanatory factors for this association is needed.



To determine, in a population-based cohort of older persons, the 2-year risk of death associated with different types of lens opacities; whether an association of mortality and lens opacity is explained by confounding risk factors such as smoking, diabetes, age, race, and sex, which are known to be related to opacity and mortality; whether lens opacity is a marker for health status; and whether there are differences in cause-specific mortality for persons with and without lens opacity.



Two-year mortality rate.



The Salisbury Eye Evaluation Project consists of a random sample of 2520 residents of Salisbury, Md, aged 65 to 84 years. At baseline, lens photographs were taken to document nuclear, cortical, posterior subcapsular cataract, and mixed opacities. Data on education, smoking, alcohol use, hypertension, diabetes and other comorbid conditions, handgrip strength, and body mass index were also collected. Two-year follow-up was conducted for mortality and cause of death.



Nuclear opacity, particularly severe nuclear opacity, and mixed opacities with nuclear were significant predictors of mortality independent of body mass index, comorbid conditions, smoking, age, race, and sex (mixed nuclear: odds ratio, 2.23; 95% confidence interval, 1.26-3.95).



Lens opacity status is an independent predictor of 2-year mortality, an association that could not be explained by potential confounders.

title: Baseline cataract type and 10-year mortality in the Italian-American Case-Control Study of age-related cataract.
abstract: Age-related cataract is reported to be associated with increased risk of death. The authors investigated the association of presence and type of cataract with mortality in the participants of the Italian-American Case-Control Cataract Study (Parma, Italy, 1987-1989), which included 1,008 persons aged 45-79 years who had age-related cataract and 469 who had clear lenses. Slit-lamp and retroillumination lens photographs were taken at baseline and graded with the Lens Opacities Classification System II. During 10 years of follow-up (range, 8.9-11.8 years; 11,318 person-years), the authors collected information on 1,429 participants and documented 339 deaths. After adjustment for age, sex, and other mortality risk factors, mixed cataracts with a nuclear/posterior subcapsular component were significantly associated with higher risk of death by Cox proportional hazards regression analyses. Hazard ratios were 2.26 (95% confidence interval (CI): 1.07, 4.76) for nuclear/posterior subcapsular and 1.62 (95% CI: 1.01, 2.61) for cortical/nuclear/posterior subcapsular opacities. In multivariate analysis, mixed types of opacity (any) were associated with increased mortality for malignancy (hazard ratio = 1.81, 95% CI: 1.04, 3.15) and "other" causes (hazard ratio = 2.29, 95% CI: 1.07, 4.92). These findings are compatible with the hypothesis that mixed types of cataract with a nuclear/posterior subcapsular component are indicators of accelerated aging.

title: Frailty, morbidity and survival.
abstract: Frailty, as a reflection of decreased physical reserve rather than disability, is assessed by various functional tests rather than by specific disease burden. We investigated association of measures of frailty to disease outcomes and survival in a population-based study of Midwestern adults. The markers of frailty we evaluated were: time to walk a measured course (gait-time), handgrip strength, peak respiratory flow rate, ability to stand from a sitting position without using arms, and best corrected visual acuity. A history of cardiovascular disease, cancer, and hypertension were obtained. Data were collected at the third examination (1998--2000) of the Beaver Dam Eye Study cohort (n=2962). Follow-up for mortality occurred up to 412 years after the 1998--2000 examinations. Markers of frailty were significantly associated with age. Values in the highest quartile (slowest) of gait-time, lowest quartile of peak expiratory flow rate, lowest quartile of handgrip strength, inability to stand from sitting in one try (those not in a wheelchair), and visual impairment were combined in an index to denote a general description of frailty. The range of the index was 0 (no frailty) to 5 (maximum frailty). Greater frailty was significantly associated with cardiovascular disease and hypertension. Frailty was associated with poorer survival over an interval of 412 years after adjusting for age, sex, hypertension, diabetes, and cardiovascular disease. Greater frailty was associated with greater likelihood of concurrent medical conditions and with decreased survival.

title: Performance-based and self-assessed measures of visual function as related to history of falls, hip fractures, and measured gait time. The Beaver Dam Eye Study.
abstract: The purpose of the study is to report relationships between visual function parameters and falls, hip fractures, and gait time in adults.



Population-based study.



The 3722 persons who participated in the 5-year follow-up of the Beaver Dam Eye Study cohort.



The visual functions measured at the examination were best-corrected visual acuity, current binocular acuity, near acuity, contrast sensitivity, and visual threshold to light. Information on falls and hip fractures was obtained by structured interview. Gait time was measured by standardized protocol.



History of falls and hip fractures increased with age, as did time to walk a measured course. Falls were more commonly reported for all persons who had poorer visual function, although not all relationships were significant in persons less than 60 years of age. In persons 60 years of age and older, hip fractures after the age of 40 were significantly related to all measures of visual function. Time to walk a measured course was significantly related to all measures of visual function.



These data indicate a consistent relationship between falls, fractures, gait time, and visual functions. Longitudinal data are necessary to accurately determine temporal relationships and to determine the likelihood of a causal association. In the interim, these data suggest that improving visual function may have benefits such as decreased traumatic events and improved mobility.

title: The eye as a model of ageing in translational research – Molecular, epigenetic and clinical aspects
abstract: The eye and visual system are valuable in many areas of translational research such as stem cell therapy, transplantation research and gene therapy. Changes in many ocular tissues can be measured directly, easily and objectively in vivo (e.g. lens transparency; retinal blood vessel calibre; corneal endothelial cell counts) and so the eye may also be a uniquely useful site as a model of ageing. This review details cellular, molecular and epigenetic mechanisms related to ageing within the eye, and describes ocular parameters that can be directly measured clinically and which might be of value in ageing research as the translational "window to the rest of the body". The eye is likely to provide a valuable model for validating biomarkers of ageing at molecular, epigenetic, cellular and clinical levels. A research agenda to definitively establish the relationship between biomarkers of ageing and ocular parameters is proposed.

title: Depression predicts mortality and hospitalization in patients with myocardial infarction complicated by heart failure.
abstract: To evaluate whether depressive symptoms are independently predictive of mortality and hospitalization among patients with acute myocardial infarction (AMI) complicated by heart failure.



The EPHESUS trial enrolled patients with AMI complicated by heart failure. Patients from Canada, the UK, and the United States completed a Medical Outcomes Study-Depression questionnaire at baseline in addition to a comprehensive clinical examination. Cox proportional hazards regression was used to determine the relationship between depressive symptoms and outcomes, including 2-year all-cause mortality and cardiovascular death or hospitalization, adjusting for baseline clinical variables.



Overall, 143 of 634 patients (22.6%) had significant depressive symptoms at baseline (Medical Outcomes Study-Depression score > or = 0.06). Depressed patients had higher 2-year mortality (29% vs 18%; P = .004) and cardiovascular death or hospitalization (42% vs 33%; P = .016). After risk adjustment, depressive symptoms remained significantly associated with mortality (hazard ratio 1.75, 95% CI 1.15-2.68, P = .01) and cardiovascular death or hospitalization (hazard ratio 1.41, 95% CI 1.03-1.93, P = .03). Results were consistent across demographic and clinical subgroups.



Depression is an independent predictor of all-cause mortality and cardiovascular death or hospitalization after AMI complicated by heart failure. Although many factors may mediate outcomes in patients with AMI, studies are warranted to evaluate whether a depression intervention can improve survival and/or reduce hospitalizations.

title: Impact of visual impairment on use of community support services by elderly persons: the Blue Mountains Eye Study.
abstract: To estimate the impact of visual impairment in older Australians on the use of community support services.



In the Blue Mountains Eye Study, 3654 people aged 49 or older were examined- 82.4% of eligible residents in an area west of Sydney, Australia. Presenting and best-corrected visual acuities were measured using a LogMAR chart. Subjects were categorized as having visual impairment if their better eye read 40 or fewer letters (20/40 or worse). Interview data included marital and other socioeconomic status measures, living status (alone or with spouse or other person), use of community support services, reliance on regular help from nonspouse family members or friends, and perceived ability to go out alone.



After adjusting for age, gender, education, living status, walking disability, and health-related factors, for each one-line (five-letter) decrease in best-corrected visual acuity, there was a corresponding increase in reliance on community support services (odds ratio [OR], 1.17; 95% confidence interval, [CI] 1.07-1.28) or combined community and family support (OR 1.22; 95% CI, 1.12-1.32). Visually impaired persons were three times as likely to use regular support services provided by the municipality (OR 3.1; 95% CI, 1.8-5.1). A similar increased reliance on regular help from community, nonspouse family members, or friends was found. Visually impaired persons were also much more likely to state that they thought they were unable to go out alone (OR 6.2; 95% CI, 2.6-14.3). The findings were similar when presenting visual acuity was used to define visual impairment or after subjects with walking disabilities were excluded. Visual impairment seemed to have a greater effect on use of community support services in women than in men.



After adjustment was made for confounding factors, visual impairment was found to affect significantly and negatively the independence of elderly people, particularly older women. Presenting visual acuity closely approximated best-corrected visual acuity in its impact on the use of community support services.

title: Design of a population-based study of visual impairment in India: The Andhra Pradesh Eye Disease Study.
abstract: Reliable population-based epidemiologic data regarding vision and ocular morbidity, as well as those about the perceptions of people regarding visual impairment and eye care, are lacking for the most part in the developing world including India. These data are the basis on which effective eye care services can be developed. To meet this need we designed the Andhra Pradesh Eye Disease Study, a population-based epidemiology study of 10,000 people in the Indian state of Andhra Pradesh. The design of this study is described in this paper. Various options for the sample size, study areas, sampling procedure, and recruitment of subjects were considered. A sample size of 10,000 people, 5,000 each in the < or = 30 and > 30 years age groups, was determined to obtain reasonable confidence in estimating the prevalence of diseases and odds ratios for risk factors of interest. A multistage sampling strategy was chosen for the study which was assumed to give a design effect of 1.5 for the estimates. One urban area, Hyderabad, and three rural areas, West Godavari, Adilabad and Mahbubnagar districts, were selected in Andhra Pradesh. Interview instruments were developed to obtain detailed information about demographic data, diet, ocular and systemic history, risk factors for eye diseases, visual function, quality of life, barriers to eye care, and knowledge about eye diseases. A detailed examination procedure was devised to obtain a broad range of normative and abnormal data related to eyes and vision. A protocol was developed for doing automated visual fields, slitlamp and fundus photography. Computer databases were made in FoxPro for data entry and subsequent analysis with SPSS. Pilot studies were done to test the instruments, procedures, and logistics of the study in urban and rural areas. Information from the Andhra Pradesh Eye Disease Study is expected to help in planning and implementation of effective long-term preventive, curative, and rehabilitative eye care services in Andhra Pradesh.

title: Blindness in the Indian state of Andhra Pradesh.
abstract: To determine the current prevalence and causes of blindness in the Indian state of Andhra Pradesh to assess if blindness has decreased since the last survey of 1986-1989.



A population-based epidemiology study, using a stratified, random, cluster, systematic sampling strategy, was conducted in the state of Andhra Pradesh in India. Participants of all ages (n = 10,293), 87.3% of the 11,786 eligible, from 94 clusters in one urban and three rural areas representative of the population of Andhra Pradesh, underwent interview and a detailed dilated ocular evaluation by trained professionals. Blindness was defined as presenting distance visual acuity < 6/60 or central visual field < 20(o) in the better eye.



Two hundred seventy-five participants were blind, a prevalence of 1.84% (95% confidence interval, 1.49%-2.19%) when adjusted for the age, sex, and urban-rural distribution of the population in 2000. The causes of this blindness were easily treatable in 60.3% (cataract, 44%; refractive error, 16.3%). Preventable corneal disease, glaucoma, complications of cataract surgery, and amblyopia caused another 19% of the blindness. Blindness was more likely with increasing age and decreasing socioeconomic status, and in female subjects and in rural areas. Among the 76 million population of Andhra Pradesh, 714,400 are estimated to have cataract-related blindness (615,600 cataract, 53,200 cataract surgery-related complications, 45,600 aphakia), and 228,000 refractive error-related blindness (159,600 myopia, 22,800 hyperopia, 45,600 refractive error-related amblyopia). If 95% of the cataract and refractive error blindness in Andhra Pradesh had been treated effectively, 3.4 and 7.4 million blind-person-years, respectively, could have been prevented. If 90% of the blindness due to preventable corneal disease and glaucoma had been prevented, another 2.7 million blind-person-years could have been prevented.



The prevalence of blindness in this Indian state has increased from 1.5% in the late 1980s to 1.84% currently, as against the target of the National Program for Control of Blindness to reduce the prevalence to 0.3% by 2000. The number of people with cataract-related blindness has not reduced even with the eye care policy focus on cataract. Reduction of blindness in India will require strategies that are more effective than those that have been pursued so far.

title: The Lens Opacities Classification System III. The Longitudinal Study of Cataract Study Group.
abstract: To develop the Lens Opacities Classification System III (LOCS III) to overcome the limitations inherent in lens classification using LOCS II. These limitations include unequal intervals between standards, only one standard for color grading, use of integer grading, and wide 95% tolerance limits.



The LOCS III contains an expanded set of standards that were selected from the Longitudinal Study of Cataract slide library at the Center for Clinical Cataract Research, Boston, Mass. It consists of six slit-lamp images for grading nuclear color (NC) and nuclear opalescence (NO), five retroillumination images for grading cortical cataract (C), and five retroillumination images for grading posterior subcapsular (P) cataract. Cataract severity is graded on a decimal scale, and the standards have regularly spaced intervals on a decimal scale. The 95% tolerance limits are reduced from 2.0 for each class with LOCS II to 0.7 for nuclear opalescence, 0.7 for nuclear color, 0.5 for cortical cataract, and 1.0 for posterior subcapsular cataract with the LOCS III, with excellent interobserver agreement.



The LOCS III is an improved LOCS system for grading slit-lamp and retroillumination images of age-related cataract.

title: Is current eye-care-policy focus almost exclusively on cataract adequate to deal with blindness in India?
abstract: India's National Programme for Control of Blindness focuses almost exclusively on cataract, based on a national survey done in the 1980s which reported that cataract caused 80% of the blindness in India. No current population-based data on the causes of blindness in India are available. We assessed the rate and causes of blindness in an urban population in southern India.



We selected 2954 participants by stratified, random, cluster, systematic sampling from Hyderabad city. Eligible participants were interviewed and given a detailed ocular assessment, including visual acuity, refraction, slitlamp biomicroscopy, applanation intraocular pressure, gonioscopy, dilatation, grading of cataract, stereoscopic fundus assessment, and automated-threshold visual fields.



2522 participants, including 1399 aged 30 years or more, were assessed. 49 participants (all aged > or =30 years) were blind (presenting distance visual acuity <6/60 or central visual field <200 in the better eye). The rate of blindness among those aged 30 years or more, adjusted for age and sex, was 3.08% ([95% CI 1.95-4.21]). Causes included cataract (29.7%), retinal disease (17.1%), corneal disease (15.4%), refractive error (12.5%), glaucoma (12.1%), and optic atrophy (11.0%). 15.7% of the blindness caused by visual-field constriction would have been missed without visual-field examination. Also without visual-field and detailed dilated-fundus assessments, blindness attributed to cataract would have been overestimated by up to 75.8%. If the use of cataract surgery in this urban population was half that found in this study, which simulates the situation in rural India, cataract would have caused 51.8% (39.4-64.2) of blindness, significantly less than the 80% accepted by current policy.



Much of the blindness in this Indian population was due to non-cataract causes. The previous national survey did not include detailed dilated-fundus assessment and visual-field examination which could have led to overestimation of cataract as a cause of blindness in India. Policy-makers in India should encourage well-designed population-based epidemiological studies from which to develop a comprehensive long-term policy on blindness in addition to dealing with cataract.

title: Burden of moderate visual impairment in an urban population in southern India.
abstract: To assess the prevalence and causes of moderate visual impairment in an urban population in southern India.



Population-based, cross-sectional study.



A total of 2522 (85.4% of the eligible) persons of all ages, including 1399 persons 30 years of age or older, from 24 clusters representative of the population of Hyderabad city.



The eligible subjects underwent a detailed ocular evaluation, including logarithm of the minimum angle of resolution (logMAR) visual acuity, refraction, slit-lamp biomicroscopy, applanation tonometry, gonioscopy, cataract grading, and stereoscopic dilated fundus evaluation. Automated threshold visual fields and slit-lamp and fundus photography were done when indicated by standardized criteria.



Moderate visual impairment was defined as presenting distance visual acuity less than 20/40 to 20/200 or visual field loss by predefined standardized conservative criteria in the better eye.



In addition to the 1% prevalence of blindness in this sample reported earlier, moderate visual impairment was present in 303 subjects, an age-gender-adjusted prevalence of 7.2% (95% confidence interval [CI], 4.5%-9.9%; design effect, 2.7). The major cause of moderate visual impairment was refractive error (59.4%, 95% CI, 52.3%-66.5%) followed by cataract (25.3%, 95% CI, 19%-31.6%). Multivariate analysis showed that the prevalence of moderate visual impairment was significantly higher in those 40 years of age or older (odds ratio, 10.9; 95% CI, 8-15) and females (odds ratio, 1.89; 95% CI, 1.41-2.53) and lower in those belonging to the highest socioeconomic status (odds ratio, 0.27; 95% CI, 0.14-0.51). However, because of the pyramidal age distribution of the population, 38.1% of the total moderate visual impairment was present in those younger than 40 years of age. The proportion of moderate visual impairment caused by refractive error was higher in the younger than in the older age groups (P < 0.0001).



Projecting the results to the 26.5% urban population of India, there would be 18.4 million (95% CI, 11.5-25.2 million) persons with moderate visual impairment in urban India alone. Refractive error was the major cause of moderate visual impairment in the population studied. The absolute proportion of moderate visual impairment in those younger than 40 years of age was considerable. The eyecare policy of India, apart from dealing with blindness, should address the issue of the relatively easily treatable uncorrected refractive error as the cause of moderate visual impairment in an estimated 10.9 million persons in urban India.

title: Smoking and its association with cataract: results of the Andhra Pradesh eye disease study from India.
abstract: To investigate the associations between tobacco smoking and various forms of cataracts among the people of a state in India.



A population-based cross-sectional epidemiologic study was conducted in the south Indian state of Andhra Pradesh (AP). A total of 10,293 subjects of all ages from one urban and three rural areas, representative of the population of AP, were interviewed, and each underwent a detailed dilated ocular evaluation by trained professionals. Data were analyzed for 7416 (72%) of the subjects aged >15 years.



Increasing age was significantly associated with all cataract types and history of prior cataract surgery and/or total cataract. In multivariate analyses, after adjusting for all demographic factors and for history of smoking, females, illiterate persons, and those belonging to the extreme lower socioeconomic status group were found to have a significantly higher prevalence of any cataract, adjusted odds ratio (OR)=1.60 (95% confidence interval [CI]: 1.24-1.96), 1.46 (95% CI: 1.17-1.70), and 1.92 (95% CI: 1.14-3.24), respectively. After adjustment, cigarette and cigar smokers had a significantly higher prevalence of any cataract, adjusted OR=1.51 (95% CI: 1.10-2.06) and 1.44 (95% CI: 1.12-1.84), respectively, compared with those who had never smoked ("never-smokers"). A significantly higher prevalence of nuclear, cortical cataract, and history of prior cataract surgery and/ or total cataract was found among cigarette smokers. A dose-response relationship was seen with respect to cigarette and cigar smoking. After adjustment, compared with never-smokers, cigarette smokers who smoked heavily (>14 "pack-years" of smoking) had a significantly higher prevalence of nuclear cataract (OR=1.65; 95% CI: 1.10-2.59), cortical cataract (OR=2.11; 95% CI: 1.38-3.24), and history of prior cataract surgery and/or total cataract (OR=2.10; 95% CI: 1.05-4.22). Nuclear cataract was significantly higher in cigar smokers (adjusted OR=1.55; 95% CI: 1.16-2.01) and in cigar smokers who smoked heavily (>21 person-years of smoking; OR=1.50; 95% CI: 1.10-1.95), compared with never-smokers.



Consistent with other studies, tobacco smoking was strongly associated with a higher prevalence of nuclear and cortical cataracts and history of prior cataract surgery in this population. These findings suggest yet another need to educate the community on the importance of cessation of tobacco smoking and perhaps incorporating an antismoking message into school health programs.

title: Risk factors for diabetic retinopathy: Findings from The Andhra Pradesh Eye Disease Study
abstract: To assess prevalence, potential risk factors and population attributable risk percentage (PAR%) for diabetic retinopathy (DR) in the Indian state of Andhra Pradesh.  A population-based study, using a stratified, random, cluster, systematic sampling strategy, was conducted in the state of Andhra Pradesh in India during 1996 and 2000. Participants from 94 clusters in one urban and three rural areas representative of the population of Andhra Pradesh, underwent a detailed interview and a comprehensive dilated ocular evaluation by trained professionals. DR was defined according to the international classification and grading system. For subjects more than or equal to 30 years of age, we explored associations of DR with potential risk factors using bivariable and multivariable analyses. Population attributable risk percent was calculated using Levin’s formula.  Diabetic retinopathy was present in 39 of 5586 subjects, an age-gender-area-adjusted prevalence of 0.72% (95% confidence interval (CI): 0.49%–0.93%) among subjects aged ≥ 30 years old, and 0.27% (95% CI: 0.17%–0.37%) for all ages. Most of the DR was either mild (51.3%) or moderate (35.9%) non-proliferative type; one subject (2.6%) had proliferative retinopathy. Multivariable analysis showed that increasing age, adjusted odds ratio (OR); 4.04 (95% CI: 1.88–8.68), middle and upper socioeconomic status group (OR); 2.34 (95% CI: 1.16–4.73), hypertension (OR); 3.48 (95% CI: 1.50–8.11) and duration of diabetes ≥ 15 years (OR); 8.62 (95% CI: 2.63–28.29) were significantly associated with increasing risk of DR. The PAR % for hypertension was 50%; it was 10% for cigarette smokers.  Extrapolating the prevalence of diabetic retinopathy in our sample to the Indian population suggests that there may be an estimated 2.77 million people with DR, approximately 0.07 million people with severe DR. As the population demographics change towards aging, this number is likely to increase further. Health care programs in India need to examine strategies to prevent diabetes and DR, as well as create the infrastructure required to manage this condition.

title: Cataract and survival in an elderly nondiabetic population.
abstract: Follow-up ranging between 6 and 8 years of the survival of a cohort of 473 elderly nondiabetic subjects randomly selected from a small English town showed an age- and sex-adjusted association between nuclear cataract at the time of baseline examination and decreased survival (P = .002). Comparing those with and without nuclear cataract, the adjusted relative hazard for death was 1.52 (95% confidence interval, 1.15 to 1.99). This effect remained virtually unchanged when also adjusted for whether the subject reported ever having been a smoker.

title: Genetic and environmental factors in age-related nuclear cataracts in monozygotic and dizygotic twins.
abstract: Age-related cataracts are a major public health problem. The relative importance of genes and environment in the causation of nuclear cataracts, the most common form of age-related cataracts, is not known.



We studied 506 pairs of female twins (226 monozygotic and 280 dizygotic) who were 50 to 79 years old (mean, 62). The amount of nuclear cataract in the right and left eyes was determined objectively by analysis of Scheimpflug lens photographs (yielding three measures) and subjectively with use of the Oxford Clinical Cataract Classification and Grading System (yielding one measure). All eight measures (four in each eye) were subsequently combined in one summary measure of nuclear cataract for each woman. A univariate maximum-likelihood model was used to estimate the variance of the genetic and environmental contributions to each of the measures.



The different measures of cataract formation were highly correlated (correlation coefficients, 0.71 to 0.94). The mean scores were similar for the right and left eyes and for monozygotic and dizygotic twins. Quantitative genetic modeling of each of the nuclear-cataract scores invariably resulted in a best-fitting model that involved additive genetic effects, unique environmental effects, and age. The common environmental and dominant genetic effects could be removed from the models without significant loss of fit. The overall heritability in the combined nuclear-cataract score (the proportion of the variance explained by genetic factors) was 48 percent (95 percent confidence interval, 42 to 54 percent); age accounted for 38 percent of the variance (95 percent confidence interval, 31 to 44 percent) and unique environmental effects for 14 percent (95 percent confidence interval, 12 to 18 percent).



Genetic effects are important even in such a clearly age-related disease as nuclear cataract, explaining almost 50 percent of the variation in the severity of this disease.

title: Ultraviolet light exposure and lens opacities: the Beaver Dam Eye Study.
abstract: Exposure to sunlight may be a risk factor for the development of cataract. The relationships between exposure to sunlight and to the ultraviolet-B (UVB) component of light and the prevalence of lens opacities were examined in the Beaver Dam Eye Study.



Persons 43 to 84 years of age residing in Beaver Dam, Wisconsin, were examined using standardized photographic assessments of lens opacities. A questionnaire about medical history and exposure to light was administered.



After adjusting for other risk factors, men who had higher levels of average annual ambient UVB light were 1.36 times more likely to have more severe cortical opacities than men with lower levels. However, UVB exposure was not found to be associated with nuclear sclerosis or posterior subcapsular opacities in men. Moreover, no associations with UVB exposure were found for women, who were less likely to be exposed to UVB.



Exposure to UVB light may be associated with the severity of cortical opacities in men. However, the lack of an association in women, the group more likely to have cortical opacities, suggests that other factors may be more important in the pathogenesis of lens opacities.

title: Effect of ultraviolet radiation on cataract formation.
abstract: To investigate the relation of ultraviolet radiation and cataract formation, we undertook an epidemiologic survey of 838 watermen (mean age, 53 years) who worked on Chesapeake Bay. The annual ocular exposure was calculated from the age of 16 for each waterman by combining a detailed occupational history with laboratory and field measurements of sun exposure. Cataracts were graded by ophthalmologic examination for both type and severity. Some degree of cortical cataract was found in 111 of the watermen (13 percent), and some degree of nuclear cataract in 229 (27 percent). Logistic regression analysis showed that high cumulative levels of ultraviolet B exposure significantly increased the risk of cortical cataract (regression coefficient, 0.70; P = 0.04). A doubling of cumulative exposure increased the risk of cortical cataract by a factor of 1.60 (95 percent confidence interval, 1.01 to 2.64). Those whose annual average exposure was in the upper quartile had a risk increased by 3.30 (confidence interval, 0.90 to 9.97) as compared with those in the lowest quartile. Analysis using a serially additive expected-dose model showed that watermen with cortical lens opacities had a 21 percent higher average annual exposure to ultraviolet B (t-test, 2.23; P = 0.03). No association was found between nuclear cataracts and ultraviolet B exposure or between cataracts and ultraviolet A exposure. We conclude that there is an association between exposure to ultraviolet B radiation and cataract formation, which supports the need for ocular protection from ultraviolet B.

title: DEHYDRATIONAL CRISES FROM SEVERE DIARRHOEA OR HEATSTROKE AND RISK OF CATARACT
abstract: The first of a series of epidemiological studies in progress in India has shown a strong association between risk of cataract and remembered episodes of dehydrational crises from severe cholera-like diarrhoeal disease. The findings suggest that severe diarrhoea is a major risk factor in early development of cataract and might account for about 36% of cases in the study area.

title: Increased mortality rates after cataract surgery. A statistical analysis.
abstract: One hundred ninety-three patients 50 to 89 years of age had cataract surgery between January 1, 1979, and December 31, 1980, at West Virginia University Medical Center, Morgantown. In comparison with 182 patients who elected one of three other surgical procedures, cataract surgery patients had a significantly higher mortality rate (P = 0.0005) than control group patients, according to life-table analysis estimates adjusted for age and sex. Patients with adult onset diabetes mellitus had slight increased survival and did not alter relative mortality. The authors' results support the hypothesis that senile cataracts may reflect systemic factors in addition to localized ocular disease.

title: Increased mortality among elderly patients undergoing cataract extraction.
abstract: One hundred sixty-seven patients aged 50 years or more had cataracts extracted between Jan 1, 1979, and Dec 31, 1979, at the New England Medical Center, Boston. In comparison with 824 patients who elected one of six other surgical procedures, when data were stratified according to age and sex, patients undergoing cataract extraction had nearly twice the mortality of the reference patients. Analysis indicated diabetic patients did not significantly alter the relative mortality. Our results support the concept that senile cataracts reflect systemic phenomena rather than only local ocular disease.

title: Prospective study of cataract extraction and risk of coronary heart disease in women.
abstract: Oxidative damage to proteins in the human lens is believed to be important in the etiology of age-related cataract. Because free radical-mediated oxidative damage to lipoproteins may accelerate atherosclerosis, the authors hypothesized that the development of cataract might be a marker for such damage and therefore might be associated with future risk of coronary heart disease (CHD). The authors followed 60,657 women aged 45--63 years and without known coronary disease, stroke, or cancer in 1984. During 10 years of follow-up (674,283 person-years), the authors documented 887 incident cases of CHD and 2,322 deaths. After adjustment for age, smoking, and other coronary risk factors, cataract extraction was significantly associated with higher risk of CHD (relative risk (RR) = 1.88, 95% confidence interval (CI): 1.41, 2.50) for total CHD, 2.44 (95% CI: 1.54, 3.89) for fatal CHD, and 1.63 (95% CI: 1.14, 2.34) for nonfatal myocardial infarction). The positive association between cataract extraction and total CHD was stronger among women with a history of diabetes (RR = 2.80, 95% CI: 1.77, 4.42) than among those without reported diabetes (RR = 1.51, 95 percent CI: 1.04, 2.18). In multivariate analyses, cataract extraction was associated with significantly increased overall mortality (RR = 1.37, 95 percent CI: 1.13, 1.66), which was entirely explained by the increased mortality from cardiovascular disease (RR = 1.84, 95% CI: 1.29, 2.64). These findings are compatible with current hypotheses relating oxidative damage and tissue aging to the development of cataract and CHD.

title: Mortality and causes of mortality among cataract-extracted patients. A 10-year follow-up.
abstract: The purpose of this study was to compare the mortality among patients undergoing intracapsular cataract extraction to the mortality in a gender-and age-identical Danish reference population, and to compare the patients' primary causes of death to those in the general population.



We reviewed medical records of patients undergoing ICCE from January 1st 1984 to December 31st 1986 at the Department of Ophthalmology, Aalborg Hospital, Denmark. Information on the deaths of these patients was obtained from the Danish National Population Register. Information on mortality in Denmark was obtained from published statistics.



We found an increased mortality among the patients with cataract with an SMR (standard mortality rate) of 1.12 (95% confidence interval 1.02-1.23). The slightly increased mortality was observed for both men and women and for all examined causes of death.



The slightly increased mortality among patients with cataract may indicate a general deterioration of health for these patients.

title: Mortality rates after cataract extraction.
abstract: Senile cataract may be a marker of generalized tissue aging. We examined this hypothesis using population-based linked health data. We hypothesized that any such association would diminish with increased use of cataract surgery. Mortality rates of those 50-95 years of age undergoing cataract surgery in British Columbia during either 1985 or 1989 were compared with the provincial population of comparable age who did not undergo cataract surgery during the study period. The 1985 cohort included 8,262 patients undergoing surgery and a comparison population of 804,303, and the 1989 cohort included 11,952 patients and a comparison population of 839,393. Using Cox regression, for the 1985 cohort, the hazard ratios for dying during follow-up were 3.2 for males 50-54.9 years of age [95% confidence limits (CL) = 2.0, 5.0] and 3.3 for females (95% CL = 1.9, 5.7). Hazard ratios for older age groups decreased with age. We also fit an additive risk model that produced excess mortalities that were less age dependent. In the 1985 analysis, these ranged from +7.1 per 1,000 (95% CL = +0.44, +13.76) to +20.3 (95% CL = +13.24, +27.36) for males and -17.5 (95% CL = -28.28, -6.72) to +2.0 (95% CL = -2.12, +6.12) for females. Findings for the 1989 analyses were similar, indicating that the association between cataracts and generalized aging remained constant despite a large increase in the use of cataract surgery.

title: Cataract patients in a defined Swedish population 1986-90: VII Inpatient and outpatient standardised mortality ratios.
abstract: Cataract surgery has at times been said to correlate with an increased death risk. We have therefore analysed the standardised death ratio in a population based cohort of patients that had undergone cataract surgery. Data for all patients undergoing cataract surgery from 1986 up to and including 1990 in the Lund Health Care District were prospectively recorded, and 5120 were retrieved for analysis. Death dates and primary death diagnoses for each patient were obtained from the Swedish Bureau of Census up to and including 1991. Standardised mortality ratios were calculated for all patients, subdivided into a number of categories: inpatients, outpatients, sex, age < 75 years, age > or = 75 years, patients with heart and circulatory diseases, with malignant tumours, and with diabetes. The cut off age was set at 74 because this divided the patients into two approximately equal groups. Using time dependent survival regression, the relative risk for dying were estimated for sex, age, and for postoperative YAG laser capsulotomy, and also for diabetic patients and patients with rheumatoid arthritis. Inpatients almost always show an increased standardised mortality ratio compared with outpatients. Young patients and diabetic patients also showed an increased standardised mortality ratio, compared with the normal population, but not older patients, who constitute the majority. Cardiovascular death diagnoses were overrepresented among the young. Cataract surgery is correlated with an increased standardised mortality ratio only in young patients and in patients with certain complicating diseases like diabetes and cardiovascular diseases.

title: National five-year mortality after inpatient cataract extraction.
abstract: We assessed the five-year mortality in all United States Medicare beneficiaries aged 65 to 79 years who underwent inpatient cataract extraction in 1984. The risk of dying within five years after cataract extraction was compared to the five-year mortality risk of the same aged persons in the United States population. Patients with cataracts who were younger than 75 years had significantly higher age-specific rates of mortality than would be predicted from United States life tables (P less than .001). For example, at the age of 65 years, patients with cataracts had 1.34 times the risk of the United States population (95% confidence interval = 1.29 to 1.41). This risk progressively declined until the age of 75 years, at which age there is little difference between the patients with cataracts and the United States population, except for the oldest women with cataracts (at the age of 79 years, relative risk = .90; 95% confidence interval = .82 to .99). Although selection factors may account for the excess mortality observed among these individuals, these data do support previous analyses that suggest an association between senile cataract and increased risk of mortality.