Relation of ocular trauma to cortical, nuclear, and posterior subcapsular cataracts: the Beaver Dam Eye Study

BACKGROUND: The consequences of minor ocular trauma in the general population are unclear. The relation of self reported ocular trauma to cortical, nuclear, and posterior subcapsular cataracts is described in a defined population. METHODS: Population based, cross sectional study involving all people aged 43 to 86 years, living in Beaver Dam, Wisconsin (n=4926). Ocular trauma was ascertained by interview and cataract was graded from lens photographs. The relation of ocular trauma to cortical, nuclear, and posterior subcapsular cataracts was examined. RESULTS: People with a history of ocular trauma were more likely to have cortical (odds ratio (OR): 1.5; 95% confidence interval (CI): 1.0 to 2.2) and posterior subcapsular (OR: 1.7; 95% CI: 1.0 to 3.1) cataracts, compared to people without a history of trauma. These associations were stronger for people with previous trauma caused by a blunt object (OR: 3.3; 95% CI: 1.6 to 6.9 for cortical cataract, and OR: 4.1; 95% CI: 1.5 to 10.8 for posterior subcapsular cataracts). However, in analyses comparing the frequencies of cataract between traumatised and non-traumatised eyes among people with unilateral ocular trauma, the ocular trauma association for cortical cataract was no longer present, although the association for posterior subcapsular cataract persisted (OR: 2.4; 95% CI: 0.8 to 7.8). CONCLUSION: The data provide evidence of a possible association between self reported ocular trauma and posterior subcapsular cataract.     

Refractive errors and incident cataracts: the Beaver Dam Eye Study

PURPOSE: To describe the relation between refractive errors and incident age-related cataracts in a predominantly white US population. METHODS: All persons aged 43 to 84 years of age in Beaver Dam, Wisconsin, were invited for a baseline examination from 1988 through 1990 and a follow-up examination 5 years later from 1993 through 1995. At both examinations, participants had refraction and photographic assessment of cataract, according to a standardized protocol. Myopia was defined as a spherical equivalent of -1.0 diopters (D) or less, hyperopia as +1.0 D or more. The relations between refractive errors at baseline and cataract at baseline (prevalent cataract), 5-year incident cataract, and incident cataract surgery were analyzed by using generalized estimating equations. RESULTS: When age and gender were controlled for, myopia was related to prevalent nuclear cataract (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.23-2.27), but not to cortical and posterior subcapsular cataracts. Myopia was not related to 5-year incident nuclear, cortical, and posterior subcapsular cataracts, but was related to incident cataract surgery (OR 1.89; CI 1.18-3.04). Hyperopia was related to incident nuclear (OR 1.56; CI 1.25-1.95) and possibly cortical (OR 1.25; CI 0.96-1.63) cataracts, but not to posterior subcapsular cataract or cataract surgery. After further adjustment for diabetes, smoking, and education, the association between myopia and incident cataract surgery was attenuated (OR 1.60; CI 0.96-2.64), but the associations between hyperopia and incident nuclear and cortical cataracts were unchanged. CONCLUSIONS: These data support the cross-sectional association between myopia and nuclear cataract seen in other population-based studies, but provide no evidence of a relationship between myopia and 5-year incident cataract. Hyperopia may be related weakly to incident nuclear and cortical cataract.     

A dose–response meta-analysis of dietary lutein and zeaxanthin intake in relation to risk of age-related cataract

Background

Lutein and zeaxanthin are thought to have beneficial effects on protecting the lens against cataract formation, but findings from epidemiologic studies have been inconsistent. We aimed to conduct a meta-analysis of prospective cohort studies to examine the association between dietary lutein and zeaxanthin intake and risk of age-related cataract (ARC).

Methods

We systematically searched MEDLINE, EMBASE, Web of Science, and Cochrane Library databases up to March 2013. Reference lists from retrieved articles were also reviewed. The adjusted relative risks (RRs) from each study were extracted to calculate a pooled estimate with its 95 % confidence interval (CI). The dose–response relationships were assessed by using generalized least-squares trend estimation.

Results

Six prospective cohort studies were identified involving 4,416 cases and 41,999 participants. For the comparison between the highest and the lowest categories of dietary lutein and zeaxanthin intake, significant inverse association were found for nuclear cataract (RR: 0.75; 95 % CI: 0.65, 0.85), but not for cortical cataract (RR: 0.85; 95 % CI: 0.53, 1.17) and for posterior subcapsular cataract (RR: 0.77; 95 % CI: 0.40, 1.13). Dose–response analysis showed that every 300 μg/d increment in dietary lutein and zeaxanthin intake was associated with a 3 %, 1 %, or 3 % reduction in the risk of nuclear cataract (RR: 0.97; 95 % CI: 0.94, 0.99), cortical cataract (RR: 0.99; 95 % CI: 0.95, 1.02), or posterior subcapsular cataract (RR: 0.97; 95 % CI: 0.93, 1.01) respectively.

Conclusions

Dietary lutein and zeaxanthin intake is associated with a reduced risk of ARC, especially nuclear cataract in a dose–response manner, indicating a beneficial effect of lutein and zeaxanthin in ARC prevention.     

Age-related cataract in a randomized trial of beta-carotene in women

PURPOSE: To examine the development of age-related cataract in a trial of beta-carotene supplementation in women. METHODS: The Women's Health Study is a randomized, double-masked, placebo-controlled trial originally designed to test the balance of benefits and risks of beta-carotene (50 mg on alternate days), vitamin E, and aspirin in the primary prevention of cancer and cardiovascular disease among 39,876 female health professionals aged 45 years or older. The beta-carotene component of the trial was terminated early after a median treatment duration of 2.1 years. Main outcome measures were visually-significant cataract and cataract extraction, based on self-report confirmed by medical record review. RESULTS: There were 129 cataracts in the beta-carotene group and 133 in the placebo group (relative risk [RR] = 0.95, 95% CI 0.75-1.21). For cataract extraction, there were 94 cases in the beta-carotene group and 89 cases in the placebo group (RR = 1.04, 95% CI 0.78-1.39). Subgroup analyses suggested a possible beneficial effect of beta-carotene in smokers. CONCLUSIONS: These randomized trial data from a large population of apparently healthy female health professionals indicate that two years of beta-carotene treatment has no large beneficial or harmful effect on the development of cataract during the treatment period.     

Age-related cataract in a randomized trial of beta-carotene in women

purpose To examine the development of age-related cataract in a trial of beta-carotene supplementation in women. methods The Women's Health Study is a randomized, double-masked, placebo-controlled trial originally designed to test the balance of benefits and risks of beta-carotene (50 mg on alternate days), vitamin E, and aspirin in the primary prevention of cancer and cardiovascular disease among 39,876 female health professionals aged 45 years or older. The beta-carotene component of the trial was terminated early after a median treatment duration of 2.1 years. Main outcome measures were visually-significant cataract and cataract extraction, based on self-report confirmed by medical record review. results There were 129 cataracts in the beta-carotene group and 133 in the placebo group (relative risk [RR] = 0.95, 95% CI 0.75-1.21). For cataract extraction, there were 94 cases in the beta-carotene group and 89 cases in the placebo group (RR = 1.04, 95% CI 0.78-1.39). Subgroup analyses suggested a possible beneficial effect of beta-carotene in smokers. conclusions These randomized trial data from a large population of apparently healthy female health professionals indicate that two years of beta-carotene treatment has no large beneficial or harmful effect on the development of cataract during the treatment period.     

Drug use and five-year incidence of age-related cataracts: The Beaver Dam Eye Study

OBJECTIVE: To evaluate incident cataract after a 5-year interval with respect to medication use. DESIGN: Population-based incidence study. MAIN OUTCOME: Incident cataract judged from standard photographs. SETTING: Study subjects were adults 43 to 86 years of age in 1988 to 1990 and again in 1993 to 1995. All participants were examined and interviewed, and photographs were taken. All procedures and grading were done by protocols at both examinations. All medications in current use, prescribed as well as over-the-counter, were brought to the examination site, and the names were recorded at that time. RESULTS: There were 678 drug preparations (active ingredients) being used at the baseline examination. Significantly lower incidences of nuclear cataracts 5 years later occurred in those who took thiazide diuretics (odds ratio [OR] = 0.79, 95% confidence interval [CI] 0.63, 1.00) and aspirin (OR = 0.76, 95% CI 0.61, 0.95) at the baseline examination. There were significantly more incident cortical cataracts in those taking oral steroids (OR = 2.59, 95% CI 1.45, 4.62), amitriptyline (OR = 2.03, 95% CI 1.09, 3.79), oral hypoglycemic agents (OR 2.06, 95% CI 1.23, 3.44), and insulin (OR = 3.38, 95% CI 1.61, 7.08). There were significantly more incident posterior subcapsular cataracts in those taking potassium-sparing diuretics (OR = 2.13, 95% CI 1.42, 3.18) and oral hypoglycemic agents (OR = 2.89, 95% CI 1.57, 5.33). Considering past use with never and current use did not alter the patterns of associations. We were not able to separate the effects of antihypertensive or diuretic agents from that of hypertension. However, hypoglycemic agents were no longer associated with any cataract type after stratifying by diabetes status. CONCLUSIONS: Although many different medications were being used at the baseline examination in the Beaver Dam Eye Study cohort, few were associated with incident cataract. However, with the high frequency of use of medications and the possibility that effects of current exposure may occur in the future, it is reasonable to follow this and other older cohorts for the development of cataract.     

Risk factors for age related cataract in a rural population of southern India: the Aravind Comprehensive Eye Study

AIM: To determine risk factors for lens opacities and age related cataract in an older rural population of southern India. METHODS: A cross sectional population based study of 5150 people aged 40 years and above from 50 clusters from three districts in southern India. The lens was graded and classified after dilation using LOCS III system at the slit lamp for cataract. Definite cataract was defined as nuclear opalescence >/=3.0 and/or cortical cataract >/=3.0 and/or PSC >/=2.0. RESULTS: Definite cataracts were found in 2449 (47.5%) of 5150 subjects and the prevalence of cataract increased with age. The age adjusted prevalence of cataract was significantly lower in males (p = 0.0002). Demographic risk factors-increasing age and illiteracy-were common for the three subtypes of cataract; females were more likely to have cortical cataracts and nuclear cataracts. Additionally, nuclear cataracts were associated with moderate smoking (OR:1.28, 95% CI:1.01 to 1.64), lean body mass indices (OR: 1.37, 95% CI: 1.17 to 1.59) and higher waist to hip ratios (OR: 0.67, 95% CI: 0.54 to 0.82); cortical cataracts with hypertension (OR: 1.39 95% CI:1.11 to 1.72), pseudoexfoliation (OR:1.53,95% CI:1.17 to 2.01), and moderate to heavy smoking; and posterior subcapsular cataracts with diabetes (OR:1.55, 95% CI:1.12 to 2.15), lean body mass (OR:1.32, 95% CI:1.11 to 1.57), and high waist to hip ratios (OR: 0.77, 95% CI: 0.62 to 0.94). CONCLUSIONS: Risk factors for age related cataract in this population do not appear to be different from those reported in other populations. Further studies are required to identify the reason for the high prevalence of age related cataract and to understand better the role of each risk factor for cataractogenesis in this population.     

Glutathione-S-transferase M1 and T1 genetic polymorphisms and the risk of cataract development: a study in the Turkish population

In this study, we aimed to determine the effects of genetic polymorphisms of glutathione-S-transferase M1 (GSTM1) and glutathione-S-transferase T1 (GSTT1) on risk of developing different subtypes of age-related cataract in the Turkish population. Using a multiplex polymerase chain reaction (PCR), GSTM1 and GSTT1 gene polymorphisms were analyzed in 195 patients with age-related cataract (75 patients with cortical, 53 with nuclear, 37 with posterior subcapsular, and 30 with mixed type) and in 136 patients of an otherwise healthy control group of similar age. GSTM1 null genotype had a significant association with the development of cataract in female subjects (p < 0.0029; OR, 2.98; 95% CI, 1.41-6.34). This relationship in female subjects was only in nuclear and mixed types cataract cases (p < 0.002; OR, 4.58; 95% CI, 1.67-12.78 and p < 0.03, respectively). There was also a statistically significant association between the combination of GSTM1-null and GSTT1-positive genotypes and the risk of cataract development in female subjects (p = 0.01; OR = 2.87; 95% CI = 1.25-6.69). Stratification by the subtypes revealed that this association was only in nuclear type cataract (p = 0.001; OR, 3.92; 95% CI, 1.34-11.71). GSTM1-null genotype or combination of the GSTM1-null and GSTT1-positive genotypes in females may be associated with increased risk of cataract development in the Turkish population.     

Assessment of cataracts from photographs in the Beaver Dam Eye Study

Presence and severity of age-related cataract was determined in adults 43 to 84 years of age in Beaver Dam, Wisconsin. Duplicate photograph gradings for nuclear sclerosis (n = 1160), cortical opacities (n = 1159), and posterior subcapsular cataract (n = 1137) were performed. There are five levels of nuclear sclerosis. Exact agreement occurred in 64.7% of the cases; agreement within one category in 99.8%. For cortical opacities, graders estimate involved area in nine segments of the lens. When the continuous scale is divided into 12 categories of severity, exact agreement varied between 73.5 and 82.4%; for agreement within one category, rates varied between 84.6 and 89.9%. For posterior subcapsular cataracts, exact agreement for involvement of the central circle occurred in 95.0% and agreement within one category occurred in 97.7%. Intraobserver comparisons disclosed similar concordance. These grading schemes are semiquantitative, reproducible, and can be performed for the large numbers of photographs from population-based studies.     

Plasma antioxidant vitamins and carotenoids and age-related cataract.

OBJECTIVE: To investigate the relationships between plasma concentrations of antioxidant vitamins and carotenoids and nuclear, cortical, and posterior subcapsular cataracts in a group of elderly men and women. DESIGN: Cross-sectional survey. PARTICIPANTS: Three hundred seventy-two men and women, aged 66 to 75 years, born and still living in Sheffield, England. METHODS: The Lens Opacities Classification System (LOCS) III was used to grade nuclear, cortical, and posterior subcapsular lens opacities. Fasting blood samples were taken to assess plasma concentrations of vitamin C, vitamin E, alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin. MAIN OUTCOME MEASURES: Logistic regression analyses of the associations between plasma vitamin concentrations and cataract subtype, adjusting for age, gender, and other risk factors. RESULTS: After adjustment for age, gender, and other risk factors, risk of nuclear cataract was lowest in people with the highest plasma concentrations of alpha-carotene (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.3-0.9, P for trend 0.006) or beta-carotene (OR, 0.7; 95% CI, 0.4-1.4, P for trend 0.033). Risk of cortical cataract was lowest in people with the highest plasma concentrations of lycopene (OR, 0.4; 95% CI, 0.2-0.8, P for trend 0.003), and risk of posterior subcapsular cataract was lowest in those with higher concentrations of lutein (OR, 0.5; 95% CI, 0.2-1.0, P for trend 0.012). High plasma concentrations of vitamin C, vitamin E, or the carotenoids zeaxanthin and beta-cryptoxanthin were not associated with decreased risk. CONCLUSIONS: These findings suggest that a diet rich in carotenoids may protect against cataract development, but because they are based on observational data, they need to be confirmed in randomized controlled trials.     

Vitamin E supplementation and cataract: randomized controlled trial

OBJECTIVE: To determine whether treatment with vitamin E (500 IU daily) reduces either the incidence or rate of progression of age-related cataracts. DESIGN: A prospective, randomized, double-masked, placebo-controlled clinical trial entitled the Vitamin E, Cataract and Age-Related Maculopathy Trial. PARTICIPANTS: Of 1906 screened volunteers, 1193 eligible subjects with early or no cataract, aged 55 to 80 years, were enrolled and followed up for 4 years. INTERVENTION: Subjects were assigned randomly to receive either 500 IU of natural vitamin E in soybean oil encapsulated in gelatin or a placebo with an identical appearance. MAIN OUTCOME MEASURES: The incidence and progression rates of age-related cataract were assessed annually with both clinical lens opacity gradings and computerized analysis of Scheimpflug and retroillumination digital lens images obtained with a Nidek EAS-1000 lens camera. The analysis was undertaken using data from the eye with the more advanced opacity for each type of cataract separately and for any cataract changes in each individual. RESULTS: Overall, 87% of the study population completed the 4 years of follow-up, with 74% of the vitamin E group and 76% of the placebo group continuing on their randomized treatment allocation throughout this time. For cortical cataract, the 4-year cumulative incidence rate was 4.5% among those randomized to vitamin E and 4.8% among those randomized to placebo (P = 0.87). For nuclear cataract, the corresponding rates were 12.9% and 12.1% (P = 0.77). For posterior subcapsular cataract, the rates were 1.7% and 3.5% (P = 0.08), whereas for any of these forms of cataract, they were 17.1% and 16.7%, respectively. Progression of cortical cataract was seen in 16.7% of the vitamin E group and 18.4% of the placebo group (P = 0.76). Corresponding rates for nuclear cataract were 11.4% and 11.9% (P = 0.84), whereas those of any cataract were 16.5% and 16.7%, respectively. There was no difference in the rate of cataract extraction between the 2 groups (P = 0.87). Lens characteristics of the participants withdrawn from the randomized medications were not different from those who continued. CONCLUSIONS: Vitamin E given for 4 years at a dose of 500 IU daily did not reduce the incidence of or progression of nuclear, cortical, or posterior subcapsular cataracts. These findings do not support the use of vitamin E to prevent the development or to slow the progression of age-related cataracts.     

Polymorphic glutathione S-transferases as genetic risk factors for senile cortical cataract in Estonians

PURPOSE: To investigate the possible association between glutathione S-transferase GSTM1, GSTM3, GSTT1, and GSTP1 polymorphism and the occurrence of age-related cataracts in Estonian patients. METHODS: Patients with cortical (155), nuclear (77), posterior subcapsular (120), mixed type (151) of senile cataract and control individuals (202) were phenotyped for GSTM1 and GSTT1 by enzyme-linked immunosorbent assay and genotyped for GSTM3 and GSTP1 by polymerase chain reaction. RESULTS: The frequency of the GSTM1-positive phenotype was significantly higher in the cortical cataract group (60.6%) than in the controls (45.0%) with odds ratio of 1.88 (95% CI, 1.23-2.94; P = 0.004). The cortical cataract risk associated with the GSTM1-positive phenotype was increased in carriers of the combined GSTM1-positive/GSTT1-positive phenotype (OR = 1.99; 95% CI, 1.30-3.11; P = 0.002) and the GSTM1-positive/GSTM3 AA genotype (OR = 2.28; 95% CI, 1.51-3.73; P < 0.001). The highest risk of cortical cataract was observed in patients having all three susceptible genotypes (OR = 2.56; 95% CI, 1.59-4.11; P < 0.001). Also, a significant interaction between the presence of the GSTP1* A allele and cortical cataract was found with prevalence of the GSTP1* A allele among the cortical cataract cases compared with the controls. Ninety-five percent of subjects with cortical cataract had the GSTP1 (AA, AB, or AC) genotype, whereas in controls 87% of persons had a genotype with GSTP1*A allele (OR = 3.1; 95% CI, 1.31-7.35; P = 0.007). In contrast to the GSTP1*A allele, the presence of the GSTP1*B allele in one or two copies leads to decreased cortical cataract risk (OR = 0.09 for GSTP1 BB genotype). CONCLUSIONS. The GSTM1-positive phenotype as well as the presence of the GSTP1*A allele may be a genetic risk factor for development of cortical cataract.     

Diabetes, cardiovascular disease, selected cardiovascular disease risk factors, and the 5-year incidence of age-related cataract and progression of lens opacities: the beaver dam eye study

PURPOSE: To describe the relationships of diabetes mellitus, cardiovascular disease, and selected cardiovascular disease risk factors to cumulative incidence of age-related cataract and to progression of lens opacities over a 5-year interval.METHODS: A follow-up examination of the Beaver Dam Eye Study cohort was performed 5 years after the baseline evaluation. Ages at the census prior to baseline ranged from 43 to 84 years of age. Protocols for examination, lens photography, and grading were the same for both examinations.RESULTS: Age at baseline was the most significant characteristic associated with incidence of nuclear, cortical, and posterior subcapsular cataract in those without diabetes (P < .001) for all cataracts. The positive association of age with cataract was found for nuclear and cortical cataract in the worse eye (P ≤ .04) but not posterior subcapsular cataract in those with diabetes. Progression of nuclear sclerosis was common, occurring in about 70% of subjects when considering either eye. Incident cortical and posterior subcapsular cataracts (P ≤ .001 for worse eye for each lesion) and progression of cortical and posterior subcapsular opacities were more common in those with diabetes (P ≤ .001 for either eye for each lesion). Increased glycated hemoglobin level was associated with increased risk of nuclear and cortical cataracts in those with diabetes. Relationships of risk factors to posterior subcapsular cataracts, especially among those with diabetes, were often in the expected direction but lacked significance possibly due to small samples.CONCLUSIONS: Diabetes mellitus is associated with incidence over 5 years of cortical and posterior subcapsular cataract and with progression of more minor cortical and posterior subcapsular lens opacities. These changes may be related to level of glycemia. Cardiovascular disease and its risk factors have little effect on incidence of any age-related cataract.     

Effect of cataract on frequency doubling perimetry in the screening mode

PURPOSE: To determine the effect of cataract on frequency doubling perimetry in the screening mode. METHODS: Frequency doubling technology perimetry in the C-20-5 screening mode was performed prospectively on 34 patients with otherwise healthy eyes before and after phacoemulsification. Cataracts were scored using the LOCS III classification, and the number of missed points (at any level of severity) on the screening field was compared before and after surgery. RESULTS: Nine patients missed at least one point pre-operatively and had no misses post-operatively. Those patients with posterior subcapsular (PSC) cataract were significantly more likely to miss points on the screening frequency doubling technology perimetry than those without posterior subcapsular cataracts (P < 0.001; Fisher exact test). In addition, the degree of posterior subcapsular cataract strongly correlated with the number of missed points pre-operatively (r = 0.97). The degree of nuclear sclerotic cataract did not correlate strongly with the number of missed points (r = 0.26), but the correlation was slightly stronger in the presence of cortical cataract (r = 0.36). CONCLUSION: Advanced age-related cataracts may cause false positive results on the screening frequency doubling technology, and the presence of even mild posterior subcapsular cataract may be a cause of false positive results and should be taken into consideration when interpreting the screening frequency doubling technology perimetry results.     

Importance of vitreous liquefaction in age-related cataract

PURPOSE: Vitrectomy is associated with the rapid progression of nuclear cataracts. This study was conducted to test the hypothesis that age-related liquefaction of the vitreous gel may also be associated with lens opacification. METHODS: Lenses from eye bank eyes were graded for nuclear, cortical, and posterior subcapsular opacities, and the amount of liquid vitreous was measured. RESULTS: Nuclear sclerosis (NS) grade, percent liquefaction, and age all correlated highly (P < 0.0001). After adjustment was made for age, the correlation between NS and percent liquefaction was 0.37 (P < 0.0001), and the correlation between age and NS after adjustment for liquefaction was 0.57 (P < 0.0001). After the eyes were stratified into age groups, the correlation between NS and percent liquefaction was found to be highest in eyes from donors aged 51 to 70. Cortical and posterior subcapsular opacities increased with age, but scores for these cataract types did not significantly correlate with vitreous liquefaction. CONCLUSIONS: Loss of vitreous gel during aging increases the risk of nuclear cataracts. Preservation or replacement of the vitreous gel may protect patients from nuclear cataract.     

Incident cataract after a five-year interval and lifestyle factors: The Beaver Dam Eye Study

CONTEXT: A population-based study to investigate risk factors for age-related eye disease was begun in 1987 in a representative American community. Incidence of cataract was subsequently evaluated. SPECIFIC OBJECTIVES: To examine the relationships of cigarette smoking, alcohol, and caffeine intakes to incidence of age-related cataracts five years later. DESIGN: Observational epidemiologic incidence study of an adult population. PARTICIPANTS AND INTERVENTION: Adults 43-84 years of age were identified during a census in 1987-1988, and examined at baseline (1988-1990) and after a five-year interval (1993-1995). MAIN OUTCOME MEASURE: Standardized protocols were used at the baseline and follow-up evaluations for exposures and for objective identification of cataracts. RESULTS: Cumulative incidence of nuclear cataract in right eyes was about 12%, cortical cataract about 8%, and posterior subcapsular cataract about 3%. In multivariable analyses of the general estimating equations type, there were significant associations between nuclear cataract and: pack-years smoked (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.01, 1.09 per 10 pack-years); and current alcohol intake (OR 1.01, 95% CI 1.00, 1.02 per 10 grams ethanol/week). Cigarette smokers were more likely to have had cataract surgery in the interval between baseline and follow-up examinations. CONCLUSIONS: Cigarette smoking and alcohol consumption were associated with modestly increased risks of incident nuclear cataract over a five-year interval.     

The epidemiology of acute endophthalmitis after cataract surgery in an Asian population

OBJECTIVE: To describe the incidence, risk factors, and clinical outcome of acute endophthalmitis after cataract extraction in a multiethnic Asian population. DESIGN: Prospective case series. PARTICIPANTS: All patients with cataract extractions performed at the Singapore National Eye Center from 1996 to 2001. METHODS: Data on patients with acute endophthalmitis cases presenting within 6 weeks after cataract surgery were prospectively collected in a standardized format. MAIN OUTCOME MEASURES: Acute endophthalmitis after cataract surgery. RESULTS: During the study period, 44 803 cataract operations (25 476 phacoemulsification and 19 327 extracapsular cataract extractions) were performed. There were 34 cases of acute endophthalmitis (average annual incidence of 0.076%), 21 of which were culture positive (average annual incidence of 0.040%). In multivariate analysis, risk of endophthalmitis was associated with phacoemulsification technique (relative risk [RR], 1.9; 95% confidence interval [CI], 0.9, 3.9; P = 0.10 for all endophthalmitis cases; RR, 3.1; 95% CI, 1.1, 9.4; P = 0.04 for culture-positive endophthalmitis cases) and the occurrence of intraoperative posterior capsule rupture (RR, 8.0; 95% CI, 3.1, 20.7; P<0.001 for all endophthalmitis cases; RR, 11.0; 95% CI, 3.7, 23.9; P<0.001 for culture-positive endophthalmitis cases). After a median follow-up of 234 days, half of the eyes achieved a final best-corrected visual acuity of 20/40. Predictors of this visual acuity included baseline acuity of counting fingers or better, culture-negative endophthalmitis, or infection caused by coagulase-negative Staphylococcus. CONCLUSION: The incidence of acute endophthalmitis after cataract extraction in Singapore is consistent with rates reported elsewhere. The phacoemulsification technique is associated with a higher risk of acute culture-positive endophthalmitis compared with extracapsular cataract extraction. Intraoperative posterior capsule rupture is associated with an 8- to 11-fold higher risk of acute endophthalmitis, suggesting that these eyes should be closely monitored for signs of infection in the immediate postoperative period.     

Incidence of age-related cataract over a 10-year interval: the Beaver Dam Eye Study

OBJECTIVE OR PURPOSE: To describe the cumulative incidence of age-related cataracts and cataract surgery over a 10-year interval. DESIGN: Prospective epidemiologic study. PARTICIPANTS: Persons 43 to 86 years of age participating in the Beaver Dam Eye Study (n = 4926 at baseline, 2764 for baseline, 5-year and 10-year follow-ups). METHODS: Questionnaires and examinations were performed according to standardized protocols in a clinic setting in the town of Beaver Dam, Wisconsin. Lens photographs were obtained with specially modified cameras and were graded according to codified rules by trained graders. MAIN OUTCOME MEASURES: Nuclear, cortical, and posterior subcapsular cataracts and cataract surgery. RESULTS: In right eyes, incident nuclear cataract occurred in 19.4%, cortical cataract in 17.4%, posterior subcapsular cataract in 6.1%, and cataract surgery in 10.8%. Incidence increased for all end points with age. Women had significantly higher incidences of nuclear cataract and cataract surgery than men. Time trends seem to be influencing the incidence of cataract surgery. CONCLUSIONS: Age-related cataracts are common events in aging. Age-specific cataract surgery incidence seems to be increasing.     

Refractive errors,axial ocular dimensions,and age-related cataracts: the Tanjong Pagar survey

PURPOSE: To describe the relationship of refractive errors and axial ocular dimensions and age-related cataract. METHODS: Population-based, cross-sectional survey of ocular diseases among Chinese men and women aged 40 to 81 years (n = 1232) living in the Tanjong Pagar district in Singapore. As part of the examination, refraction and corneal curvature were determined with an autorefractor, with refraction further refined subjectively. Ocular dimensions, including axial length, anterior chamber depth, lens thickness, and vitreous chamber depth, were measured with an A-mode ultrasound device. Lens opacity was graded clinically according to the Lens Opacity Classification System (LOCS) III system. Refraction, biometry, and cataract data on right (n = 989) and left (n = 995) eyes were analyzed separately. RESULTS: In analyses controlling for age, gender, education, diabetes, and cigarette smoking, nuclear cataract was associated with myopia (-1.35 D vs. -0.11 D, P < 0.001, comparing right eyes with and without nuclear cataract), but not with any specific biometric component. Cortical cataract was associated with thinner lenses (4.67 mm vs. 4.79 mm, P = 0.001, comparing right eyes with and without cortical cataract), but not with refraction and other biometric components. Posterior subcapsular cataract was associated with myopia (-1.80 D vs. -0.39 D, P < 0.001, comparing right eyes with and without posterior subcapsular cataract), deeper anterior chamber (3.00 mm vs. 2.89 mm, P = 0.02), thinner lens (4.62 mm vs. 4.77 mm, P = 0.001), and longer vitreous chamber (15.78 mm vs. 15.57 mm, P = 0.09), but not with overall axial length and corneal curvature. Adjustment for vitreous chamber depth attenuated the association between posterior subcapsular cataract and myopia by 65.5%, but did not substantially change the association between nuclear cataract and myopia. CONCLUSIONS: These population-based data support the associations between nuclear and posterior subcapsular cataracts and myopia reported in previous studies. Posterior subcapsular cataract is also associated with deeper anterior chamber, thinner lens, and longer vitreous chamber, with vitreous chamber depth explaining most of the association between posterior subcapsular cataract and myopia.     

Cardiovascular disease,vascular risk factors and the incidence of cataract and cataract surgery: The Blue Mountains Eye Study

PURPOSE To assess whether an association exists between cardiovascular disease, vascular risk factors and incident cataract and cataract surgery. METHODS The Blue Mountains Eye Study examined 3654 participants =49 years of age during 1992–4, then 2335 survivors (75.1%) after five years. Trained interviewers administered a vascular history questionnaire; height, weight and blood pressure were measured. Lens photographs from both examinations were graded for presence of cortical, nuclear or posterior subcapsular cataract. RESULTS Obesity (body mass index =30kg/m 2 ) was significantly associated with increased incidence of both cortical [odds ratio (OR) 1.6, 95% confidence interval (CI) 1.2–2.2] and posterior subcapsular cataract (OR 2.1, CI 1.2–3.7). Hypertensive participants using medication and aged less than 65 years at baseline had a higher incidence of posterior subcapsular cataract (OR 3.4, 95% CI 1.3–8.4) than normotensive subjects. A history of angina was associated with higher cataract surgery incidence (OR 2.1, 95% CI 1.3–3.5). CONCLUSIONS These longitudinal data provide some evidence supporting a relationship between cardiovascular disease, vascular risk factors and incident cataract and cataract surgery. The findings confirm a number of associations previously documented in cross-sectional data.