Anthropometric status and cataract: the Salisbury Eye Evaluation project

Prevalence of refractive errors in population aged 50 years and over: The Gilan eye study

PURPOSE

To describe the prevalence of refractive error (RE) and its association with other environmental and health factors among population aged ≥50 years who lived in Gilan, Iran in 2014.

METHODS

In this population-based cross-sectional study, 3281 individuals aged ≥50 years living in Gilan for at least 6 months were enrolled. The prevalence of different types of REs including myopia (spherical equivalent (SE)≤-0.50D), high myopia (SE ≤ -6.00D), hyperopia (SE≥ + 0.50D), high hyperopia (SE≥ + 3.00D), astigmatism (cylinder < -0.50D) and high astigmatism (cylinder < -2.25D) were determined. Anisometropia was defined as the SE difference of ≥1.00D between the two eyes. Associated factors including age, body mass index (BMI) and education were also studied.

RESULTS

2587 eligible individuals (58% female subjects) with the mean age of 62.6 ± 8.8 years participated (87.6% response rate). The prevalence of myopia, hyperopia and astigmatism was 19.2%, 48.6% and 57.4%, respectively. 3.6% high hyperopia, 0.5% high myopia and 4.5% high astigmatism were identified. The positive simultaneous effects3 of older age (Odds Ratio (OR) = 3.14), nuclear (OR = 1.71) and posterior subcapsular (OR = 1.61) cataracts as well as the negative effects of higher levels of education (OR = 0.28) were obtained on myopia. Higher BMI was found as a risk factor for hyperopia (OR = 1.67), while older patients were less likely to be hyperopic (OR = 0.31).

CONCLUSION

Higher incidence of myopia and astigmatism was found in patients aged over 70 years. It was also found that patients at older ages who suffered with cataracts were at a higher risk of myopia, while elderly people with greater BMI were at a higher risk of hyperopia.

Voxel-Mirrored Homotopic Connectivity Is Altered in Meibomian Gland Dysfunction Patients That Are Morbidly Obese

Purpose: To investigate the altered functional connectivity (FC) of the cerebral hemispheres in patients with morbid obesity (MO) with meibomian gland dysfunction (MGD) by voxel-mirrored homotopic connectivity (VMHC). Methods: Patients and matched healthy controls (HCs) were recruited, and all subjects underwent functional resonance magnetic imaging (fMRI), and VMHC results were processed statistically to assess the differences in FC in different brain regions between the two groups. We further used ROC curves to evaluate the diagnostic value of these differences. We also used Pearson’s correlation analysis to explore the relationship between changes in VMHC values in specific brain regions, visual acuity, and Mini-Mental State Examination (MMSE) score. Conclusions: Patients with morbid obesity and MGD had abnormal FC in the cerebral hemispheres in several specific brain areas, which were mainly concentrated in pathways related to vision and perception and may correlate to some extent with the clinical presentations of the patients.

FACTORS ASSOCIATED WITH PREVALENT LENS OPACITIES IN CHINESE AMERICAN ADULTS: THE CHINESE AMERICAN EYE STUDY

PURPOSE

To identify risk factors associated with lens opacities in Chinese Americans.

METHODS

A cross-sectional population-based study of 4,582 Chinese Americans ≥50 years residing in Monterey Park, California. Participants completed a comprehensive clinical examination with lens assessment using the Lens Opacities Classification System II, with lens opacities defined by a grade ≥2 in either eye. Participants were considered to have nuclear-only, cortical-only, or posterior subcapsular (PSC)-only if that was the only type of opacity present in both eyes.

RESULTS

Cortical-only opacity was associated with older age, diabetes mellitus (OR 1.5, 95%CI 1.1-2.1), and family history of cataracts (OR 1.5, 95%CI 1.2-1.9). Nuclear-only opacity was associated with older age, diabetes mellitus (OR 1.4, 95%CI 1.1-1.9), greater waist-to-hip ratio (OR 1.2, 95%CI 1.1-1.4), and high-density lipoprotein (OR 1.1, 95%CI 1.02-1.2). Mixed-type opacities were associated with older age, greater waist-to-hip ratio (OR 1.3, 95%CI 1.1-1.6), and higher HbA1 c (OR 1.3, 95%CI 1.1-1.4). Taller height (OR 0.7, 95%CI 0.6-0.8), greater weight (OR 0.98, 95%CI 0.97-0.99), and higher diastolic pressure (OR 0.98, 95%CI 0.96-0.99) were protective.

CONCLUSION

CHES identified a strong, dose-response association between age and all types of prevalent lens opacities, which suggests an increasing cataract burden in Chinese Americans based on aging populations. CHES results demonstrate general consistency with previous population-based studies in regard to more sedentary lifestyle exposures (e.g., Westernized lifestyle) and prevalent cortical-only, nuclear-only, and mixed-type opacities, yet also identified further sedentary lifestyle exposures associated with prevalent lens opacities. Improved glycemic control and a more active lifestyle that minimizes factors contributing to metabolic syndrome may help reduce the burden of vision loss associated with lens opacities.

Intake of Vegetables and Fruits and the Risk of Cataract Incidence in a Japanese Population: The Japan Public Health Center-Based Prospective Study

Background

Although the consumption of vegetables and fruits is reported to influence the risk of cataract, no prospective study of this association from Asia has yet appeared. Here, we investigated the association between vegetable and fruit intake and cataract incidence in a large-scale population-based prospective cohort study in Japan.

Methods

This study included 32,387 men and 39,333 women aged 45–74 years who had no past history of cataract and had completed a dietary questionnaire of the Japan Public Health Center-based Prospective Cohort Study. The incidence of cataract was evaluated after 5-year follow-up. We used multiple logistic regression analyses to estimate the sex-specific odds ratios (ORs), with adjustment for confounding factors.

Results

We identified 1,836 incident cataracts in 594 men and 1,242 women. In men, the OR for cataract was decreased with higher intake of vegetables (OR_{Q5 vs Q1}, 0.77; 95% confidence interval [CI], 0.59–1.01; P_trend across quartile categories = 0.03) and cruciferous vegetables (OR_{Q5 vs Q1}, 0.74; 95% CI, 0.57–0.96; P_trend = 0.02). In contrast, the OR for cataract was increased with higher intake of vegetables among women (OR_{Q5 vs Q1}, 1.28; 95% CI, 1.06–1.53; P_trend = 0.01). Green and yellow vegetable and fruit intake were not associated with cataract in either sex.

Conclusions

This study suggests that vegetables may reduce the risk of cataract in men, but not in women.

The Relationship Between Serum 25-Hydroxyvitamin D Levels and Nuclear Cataract in the Carotenoid Age-Related Eye Study (CAREDS), an Ancillary Study of the Women's Health Initiative

PURPOSE

To investigate the relationship between serum 25-hydroxyvitamin D (25[OH]D) levels and nuclear cataract among participants of the Carotenoids in Age-Related Eye Disease Study (CAREDS), an ancillary study of the Women's Health Initiative (WHI) Observational Study (OS).

METHODS

Nuclear cataract was assessed from slit lamp photographs (2001-2004) taken 6 years after collecting serum analyzed for 25(OH)D levels at WHI baseline (1994-1998) in 1278 CAREDS participants age 50 to 79 years. Multivariate (age, iris color, smoking, pulse pressure) odds ratios (ORs) for nuclear cataract (nuclear opacities > level 4 or cataract extraction) by quintiles of serum 25(OH)D were estimated using logistic regression.

RESULTS

No significant association was observed between serum 25(OH)D and nuclear cataract among women of all ages (age-adjusted OR [95% confidence interval (CI)] 0.97 [0.65-1.45]). However, there was a significant age interaction (P for interaction = 0.04). There were no significant associations in the women 70 years or older. In women younger than 70 years, we observed an inverse association between serum 25(OH)D and nuclear cataract (multivariate adjusted ORs [95% CI] 0.54 [0.29-0.99] and 0.66 [0.36-1.20] for quintiles 4 and 5 vs. 1, respectively; P = 0.03). Further adjustment for 25(OH)D determinants (body mass index, vitamin D intake, and UVB exposure) attenuated this association.

CONCLUSIONS

Serum 25(OH)D levels were unrelated to nuclear opacities in this study sample. However, exploratory analyses suggest a protective association in women younger than 70 years. Further investigations of the relationship between vitamin D and nuclear lens opacities are warranted.

The Gender-Dependent Association between Obesity and Age-Related Cataracts in Middle-Aged Korean Adults

The aim of this study was to investigate the association of central and abdominal obesity with the prevalence of cataracts in a middle-aged Korean population. This retrospective cross-sectional study was based on the data collected from the Korea National Health and Nutrition Examination Survey 2008–2009, in which 4,914 subjects were examined. Ophthalmological examinations were performed to determine the presence of a nuclear, cortical, or posterior subcapsular cataract. Both general obesity (a body mass index ≥25 kg/m²) and abdominal obesity (a waist circumference ≥90 cm for men and ≥80 cm for women) were significantly associated with the occurrence of cataracts among middle-aged women [adjusted odds ratio (aOR), 1.32; 95% confidence interval (CI), 1.03–1.69; and aOR, 1.40; 95% CI, 1.06–1.85, respectively], while abdominal obesity was significantly inversely associated with the occurrence of cataracts among middle-aged men (aOR, 0.76; 95% CI, 0.58–1.01; and aOR, 0.66; 95% CI, 0.49–0.89, respectively). We report a difference in the association between obesity and the prevalence of cataracts based on gender.

Association between cataract and the degree of obesity

PURPOSE

To investigate the association between the degree of obesity and cataract.

METHODS

We examined 3248 subjects (1421 men and 1827 women) aged 50 years and older who did not have a previous cataract operation. Data were derived from the fourth Korea National Health and Nutrition Examination Survey (2009). Cataract was evaluated by using Lens Opacities Classification System III. Body mass index was categorized into four groups (underweight, <18.5 kg/m(2); normal weight, 18.5 to 22.9 kg/m(2); overweight, 23.0 to 24.9 kg/m(2); and obese, ≥25.0 kg/m(2)). Association between the degree of obesity and cataract was evaluated using logistic regression analyses with adjustments of age, the total pack-years of cigarettes smoked, the amount of pure alcohol (g) consumed per day, daily time spent in vigorous physical activity, diabetes mellitus, sunlight exposure, education level, and income.

RESULTS

Compared with the normal-weight group, the overweight group had significantly lower risk of any type of cataract (odds ratio, 0.70; 95% confidence interval, 0.50 to 0.97) in men and (odds ratio, 0.70; 95% confidence interval, 0.51 to 0.97) in women in the multiple logistic regression analyses. We could not find any unusual lifestyles or metabolic risks for explaining this low cataract prevalence in the overweight groups. However, nutrient intakes (e.g., vitamin B2, niacin, vitamin C, and vitamin A) were highest in the overweight group.

CONCLUSIONS

The overweight group had significantly lower risk of cataract formation than the normal-weight group in Korean population.

Cataract subtype risk factors identified from the Korea National Health and Nutrition Examination survey 2008-2010

Background

To assess the socio-demographic and health-related risk factors associated with cataract subtypes in Korea.

Methods

A total of 11,591 participants (aged ≥40 years) were selected from the Korean National Health and Nutrition Examination Survey between 2008 and 2010. The Korean Ophthalmologic Society conducted detailed ophthalmologic examinations on these participants based on the Lens Opacity Classification System III. Risk factors for developing any type of cataract, and its subtypes (nuclear, cortical, posterior subcapsular and mixed), were identified from univariate and multivariate logistic regression analysis.

Results

The prevalence of cataracts was 40.1% (95% CI, 37.8 − 42.3%) in participants over 40 years old. Older age, lower monthly household income, lower education, hypercholesterolemia, hypertension, and diabetes mellitus (DM) were independent risk factors for development of any cataract. Older age, lower monthly household income, lower education, hypercholesterolemia, and DM were independent risk factors for development of pure cortical cataracts. Older age, lower education, metabolic syndrome, and DM were independent risk factors for development of pure nuclear cataracts. Older age and DM were independent risk factors for development of pure posterior subcapsular cataracts. Older age, lower monthly household income, lower education, and DM were independent risk factors for development of mixed cataracts.

Conclusion

Although socioeconomic disparities are related to cataract development, this study identified several “modifiable” risk factors that may help to lower the incidence of cataracts and associated vision loss. Improved control of blood pressure, blood, glucose, and cholesterol may help to reduce the incidence of cataracts in the general Korean population.

Racial differences in lens opacity incidence and progression: the Salisbury Eye Evaluation (SEE) study

PURPOSE

To evaluate racial differences in nuclear and cortical lens opacity incidence and progression over a 2-year period in an older American population.

METHODS

Prospective population-based cohort study of a multiethnic population of 2520 people (26% African-American and 74% Caucasian), 65 to 84 years of age, living in Salisbury, Maryland. Data at baseline included race, education level, past steroid use, smoking status, alcohol status, sunlight exposure, and history of hypertension and diabetes. Lens photographs were taken at baseline and at 2-year follow-up and were graded using the Wilmer grading scheme. Multiple logistic regression models were used to examine the independent associations between race, as well as other risk factors, and incidence and progression of cortical and nuclear opacities.

RESULTS

AFRICAN-AMERICANS HAD LOWER RATES OF NUCLEAR OPACITY INCIDENCE (ODDS RATIO [OR]: 0.52; 95% Confidence Interval [CI]: 0.35-0.76) and nuclear opacity progression (OR: 0.60; 95% CI: 0.38-0.92) compared with Caucasians. African-Americans had higher rates of cortical opacity incidence (OR: 1.90; 95% CI: 1.21-2.98) and cortical opacity progression (OR: 1.72; 95% CI: 1.21-2.45) compared with Caucasians. Additionally, nuclear opacity incidence was associated with age, female sex, and current smoking status. Nuclear progression was associated with past smoking and current smoking. Cortical opacity incidence was associated with female sex, Ultraviolet-B exposure, and a history of diabetes. Cortical opacity progression was associated with current smoking status.

CONCLUSIONS

Differences by race in the type of cataract incidence and progression, even adjusting for personal and environmental risk factors, deserve further exploration.

Risk factors associated with incident cataracts and cataract surgery in the Age-related Eye Disease Study (AREDS): AREDS report number 32

OBJECTIVE

To investigate potential risk factors associated with incident nuclear, cortical, and posterior subcapsular (PSC) cataracts and cataract surgery in participants in the Age-Related Eye Disease Study (AREDS).

DESIGN

Clinic-based prospective cohort study.

PARTICIPANTS

Persons (n = 4425) 55 to 80 years of age enrolled in a controlled clinical trial of antioxidant vitamins and minerals, AREDS, for age-related macular degeneration and cataract.

METHODS

Lens photographs were graded centrally for nuclear, cortical, and PSC opacities using the AREDS system for classifying cataracts. Type-specific incident cataracts were defined as an increase in cataract grade from none or mild at baseline to a grade of moderate at follow-up, also with a grade of at least moderate at the final visit, or cataract surgery. Cox regression analyses were used to assess baseline risk factors associated with type-specific opacities and cataract surgery.

MAIN OUTCOME MEASURES

Moderate cataract was defined as a grade of 4.0 or more for nuclear opacity, 10% or more involvement within the full visible lens for cortical opacity, and 5% or more involvement of the central 5-mm circle of the lens for PSC opacity. These were graded on baseline and annual lens photographs.

RESULTS

A clinic-based cohort of 4425 persons 55 to 80 years of age at baseline was followed up for an average of 9.8±2.4 years. The following associations were found: increasing age with increased risk of all types of cataract and cataract surgery; males with increased risk of PSC and decreased risk of cortical cataracts; nonwhite persons with increased risk of cortical cataract; hyperopia with decreased risk of PSC, nuclear cataract, and cataract surgery; Centrum (Wyeth Consumer Healthcare, Madison, NJ) use with decreased risk of nuclear cataract; diabetes with increased risk of cortical, PSC cataract, and cataract surgery; higher educational level with decreased risk of cortical cataract; and smoking with increased risk of cortical cataract and cataract surgery. Estrogen replacement therapy in female participants increased the risk of cataract surgery.

CONCLUSIONS

These findings largely are consistent with the results of previous studies, providing further evidence for possible modifiable risk factors for age-related cataract.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Association of body mass index with risk of age-related cataracts in a middle-aged Japanese population: the JPHC Study

OBJECTIVES

Many epidemiological studies have demonstrated that body mass index (BMI) is associated with the risk of developing age-related cataracts. These reports have suggested that high and low BMIs can affect the onset or progression of age-related visual impairment. However, few prospective studies have examined this relationship in a general Asian population. Therefore, in this study, we investigated whether BMI was associated with an increased risk of age-related cataracts by performing a 5-year prospective population-based study in a middle-aged Japanese population.

METHODS

This 5-year population-based study included 35,365 men and 40,825 women (aged 45-74 years), who were recruited into the Japan Public Health Center (JPHC)-based Prospective Study and had not reported cataracts in a baseline survey. The self-reported diagnosis of age-related cataracts was used in the analysis of this study.

RESULTS

At follow up, 1,004 men (2.84%) and 1,807 women (4.43%) reported new diagnoses of age-related cataracts. The multivariate odds ratios (ORs) for those in the lowest and the highest BMI categories, compared with a BMI category of 21.0-22.9 as a reference point (OR, 1.00), were 1.29 [95% confidence interval (CI) 0.93-1.79] and 1.15 (95% CI 0.96-1.39) in men, and 1.23 (95% CI 0.97-1.55) and 1.19 (95% CI 1.04-1.36) in women.

CONCLUSIONS

Previous studies have suggested high BMI as a risk factor of age-related cataracts for Caucasian populations in developed countries while low BMI for populations living in developing countries. In contrast to those studies, the present large-cohort study showed a U-shaped association between BMI and the incidence of cataracts in Japanese men and women.

Risk for radiation-induced cataract for staff in interventional cardiology: is there reason for concern?

OBJECTIVES

To examine the prevalence of radiation-associated lens opacities among interventional cardiologists and nurses and correlate with occupational radiation exposure.

BACKGROUND

Interventional cardiology personnel are exposed to relatively high levels of X-rays and based on recent findings of radiation-associated lens opacities in other cohorts, they may be at risk for cataract without use of ocular radiation protection.

METHODS

Eyes of interventional cardiologists, nurses, and age- and sex-matched unexposed controls were screened by dilated slit lamp examination and posterior lens changes graded using a modified Merriam-Focht technique. Individual cumulative lens X-ray exposure was calculated from responses to a questionnaire and personal interview.

RESULTS

The prevalence of radiation-associated posterior lens opacities was 52% (29/56, 95% CI: 35-73) for interventional cardiologists, 45% (5/11, 95% CI: 15-100) for nurses, and 9% (2/22, 95% CI: 1-33) for controls. Relative risks of lens opacity was 5.7 (95% CI: 1.5-22) for interventional cardiologists and 5.0 (95% CI: 1.2-21) for nurses. Estimated cumulative ocular doses ranged from 0.01 to 43 Gy with mean and median values of 3.4 and 1.0 Gy, respectively. A strong dose-response relationship was found between occupational exposure and the prevalence of radiation-associated posterior lens changes.

CONCLUSIONS

These findings demonstrate a dose dependent increased risk of posterior lens opacities for interventional cardiologists and nurses when radiation protection tools are not used. While study of a larger cohort is needed to confirm these findings, the results suggest ocular radio-protection should be utilized.

The epidemiology of cataract: a study in Greece

PURPOSE

We conducted a case-control study to identify risk factors for cataract in the Mediterranean Greek population. Three hundred and fourteen cases and 314 frequency-matched controls of both genders, aged 45-85, attending the ophthalmology department of a major teaching hospital in Athens, Greece, were included in the study.

METHODS

Cases were medically diagnosed and classified. Controls were healthy visitors without cataract. A detailed questionnaire, covering demographic, socioeconomic, somatometric, lifestyle and medical history variables, provided data on possible risk factors for cataract. Analyses were conducted through multiple logistic regression.

MAIN OUTCOME MEASURES

Cataract overall and by type: nuclear, cortical and posterior subcapsular (PSC).

RESULTS

  Statistically significant increased risk for cataract overall was found for current (OR = 1.99, 95%CI: 1.23-3.23) and ex-smokers (OR = 1.64, 95%CI: 1.02-2.70), history of coronary heart disease (OR = 2.25, 95%CI: 1.43-3.55), family history of ophthalmologic diseases (OR = 1.51, 95%CI: 1.03-2.20) and higher sunlight exposure at the beach (OR = 2.26, 95%CI: 1.37-3.72) as well as at work (OR = 2.03, 95%CI: 1.32-3.12). Use of measures protecting against sunlight at the beach, i.e. hat (OR = 0.58, 95%CI: 0.39-0.85) and vision repair spectacles (OR = 0.44, 95% CI: 0.30-0.65), were associated with reduced risk. RESULTS for cataract overall were also evident for the nuclear type and in most circumstances for PSC type, but were only suggestive for the cortical type of cataract.

CONCLUSION

We identified certain possible risk factors for age-related cataract. In a Mediterranean Greek population, we found that smoking, use of cortisone drops, cardiovascular heart disease and sunlight exposure increase the risk for cataract, while use of hat and vision repair spectacles act protectively.

Healthy diets and the subsequent prevalence of nuclear cataract in women

OBJECTIVE

To assess the association between healthy diet scores and prevalence of nuclear cataract in women.

METHODS

The association between healthy diet scores, which reflect adherence to the US dietary guidelines, and prevalence of nuclear cataract determined 4 to 7 years later was assessed in a sample of Women's Health Initiative Observational Study participants (aged 50-79 years) residing in Iowa, Wisconsin, and Oregon. Scores on the 1995 Healthy Eating Index, which reflect adherence to 1990 guidelines, were assigned from responses to food frequency questionnaires at the Women's Health Initiative baseline (1994-1998). Presence of nuclear cataract was determined from slitlamp photographs and self-reports of cataract extractions were assessed from May 1, 2001, to January 31, 2004, in 1808 women participating in the Carotenoids in Age-Related Eye Disease Study.

RESULTS

Having a high 1995 Healthy Eating Index score was the strongest modifiable predictor of low prevalence of nuclear cataract among numerous risk factors investigated in this sample. The multivariate-adjusted odds ratio for high vs low quintile for diet score was 0.63 (95% confidence interval, 0.43-0.91). Higher prevalence of nuclear cataract was also associated with other modifiable factors (smoking and marked obesity) and nonmodifiable factors (having brown eyes, myopia, and high pulse pressure). Vitamin supplement use was not related to cataract.

CONCLUSION

These data add to the body of evidence suggesting that eating foods rich in a variety of vitamins and minerals may contribute to postponing the occurrence of the most common type of cataract in the United States.

Interrelationships between nutritional status, socioeconomic factors, and lifestyle in Indian cataract patients

OBJECTIVES

The etiology of cataracts in the Asian subcontinent is not well understood. The aim of this study was to understand the differences in nutritional and lifestyle-related etiology of cataract in a high-income group (HIG) and a low-income group (LIG).

RESEARCH METHODS

A cross-sectional survey was conducted on 140 cataract patients, aged 50-70 y, and 100 age- and sex-matched healthy controls. Socioeconomic information and habitual dietary intake were recorded by interview method. Cataract grading was given by ophthalmologists using a slit-lamp biomicroscope.

RESULTS

In HIG patients, there was a delay of 10 y in the onset of cataracts as compared to LIG patients. Sixty-seven percent of LIG patients were alcoholic and 80% had a family history of cataracts. Further, among LIG male patients, 45%-87% were uneducated and 80% were addicted to tobacco. The intake of animal foods and fried foods was significantly higher in all the patient groups than controls (P<0.001). The intake of vegetables, fruits, salads, and tea were higher in all the controls than patients (P<0.001). For HIG male patients, between alcoholics and non-alcoholics, significant differences were noted for antioxidant status and soluble to total proteins ratio of lens. Similar differences were seen between HIG male smokers and non-smokers. Multiple regression analysis of solubility and opacity of lens indicated influence of family size, sunlight exposure, and systolic blood pressure for predisposition of cataracts.

CONCLUSIONS

Along with high systolic blood pressure, waist:hip ratio, family size, sunlight exposure, and increased consumption of tobacco and alcohol were the risk factors for cataracts.

Relation of age-related cataract with obesity and obesity genes in an Asian population

Obesity shows an inconsistent association with cataract. Causality has not been established. Polymorphisms at the fat mass- and obesity-associated (FTO) locus are associated with obesity and offer an opportunity to examine the obesity-cataract association using a mendelian randomization approach. The authors conducted a population-based study among Singaporean Malay adults (2004-2006) in which nuclear, cortical, and posterior subcapsular (PSC) cataracts were assessed and defined by slit-lamp examination using Lens Opacity Classification System III. Obesity was defined as body mass index (weight (kg)/height (m)(2)) > or =30. The study included 3,000 subjects, of whom 1,339 (44.6%) had cataract (848 (28.3%) nuclear, 939 (31.3%) cortical, and 285 (9.5%) PSC). After multivariable adjustment for age, gender, diabetes, hypertension, smoking, and education, obesity was significantly associated with cortical (odds ratio (OR) = 1.31, 95% confidence interval (CI): 1.01, 1.71) and PSC (OR = 1.60, 95% CI: 1.10, 2.32) cataracts but not nuclear cataract. FTO single nucleotide polymorphisms known to be associated with obesity in this study population were not associated with cortical or PSC cataract but were associated with nuclear cataract (OR = 1.33, 95% CI: 1.11, 1.58), even in multivariate analyses controlling additionally for body mass index, diabetes, hypertension, and smoking (OR = 1.30, 95% CI: 1.08, 1.55). These results do not support a causal association between obesity and cortical or PSC cataract. The FTO gene may be involved in the pathogenesis of nuclear cataract.

Metabolic syndrome components in relation to risk of cataract extraction: a prospective cohort study of women

OBJECTIVE

To investigate the association between metabolic syndrome and some of its components with the incidence of cataract extraction.

DESIGN

Population-based prospective cohort study.

PARTICIPANTS

A total of 35,369 women, participating in the Swedish Mammography Cohort, aged 49 to 83 years, who completed a self-administered questionnaire about anthropometric measurements and lifestyle factors in 1997.

METHODS

The women were followed from September of 1997 to October of 2005. The cohort was matched with registers of cataract extraction in the study area.

MAIN OUTCOME MEASURES

Incident surgical extraction of age-related cataract.

RESULTS

We identified 4508 incident cases of cataract extractions during 98 months of follow-up. In multivariate analysis, women with a waist circumference >or=80 cm had an 8% increased risk of cataract extraction (rate ratio [RR], 1.08; 95% confidence interval [CI], 0.99-1.17). Women with diabetes had a 43% increased risk of cataract extraction (RR, 1.43; 95% CI, 1.10-1.86), and hypertension was associated with a 12% increased risk (RR, 1.12; 95% CI, 0.99-1.26). Women with all 3 components of the metabolic syndrome (waist >or=80 cm, diabetes, and hypertension) had a 68% increased risk of cataract extraction (RR, 1.68; 95% CI, 1.40-2.02) compared with women without any of these components. Among women aged less than 65 years at baseline with all 3 components of metabolic syndrome, the risk of cataract extraction was approximately 3-fold more (RR, 2.80; CI, 1.94-4.03).

CONCLUSIONS

Metabolic syndrome and its components, abdominal adiposity, diabetes, and hypertension, seem to be associated with an increased risk for cataract extraction, especially among women aged less than 65 years.

Obesity and eye diseases

The prevalence of obesity has reached epidemic proportions in many countries. Although its impact on overall health is well documented, less is known about the ocular manifestations of obesity. Among different eye diseases, obesity has been linked with age-related cataract, glaucoma, age-related maculopathy, and diabetic retinopathy. Numerous population-based and prospective studies support an association between obesity and risk of age-related cataract. However, the nature and strength of these associations, particularly with the different cataract subtypes, remains to be determined. There is strong evidence that obesity is associated with elevated intraocular pressure, but there is no convincing data to support a more direct association between obesity and glaucomatous optic neuropathy. Studies to date have not found a consistent pattern of association between obesity and risk of age-related maculopathy or diabetic retinopathy. Thus, although obesity may be a risk factor for many ocular conditions, the present literature is inadequate to establish any convincing associations. Furthermore, whether weight loss reduces the risk of eye diseases remains unresolved. Because of the potential public health impact of obesity, there is a greater need to understand its ocular effects.

Risk factors for cataract subtypes waterclefts and retrodots: two case–control studies

Waterclefts and retrodots are independently associated with visual impairment, yet a review identified no data on risk factors.

PURPOSE

To investigate risk factors for these two human lens cataract subtypes.

METHOD

Two nested case-control studies: The host study comprised 1078 subjects (55 years) attending the Somerset and Avon Eye Study (SAES). In total, 197 watercleft cases (Oxford grade 0.2 in either eye) and 199 retrodot cases (Oxford grade 1.0 in either eye) were individually age/gender matched to controls. Detailed ophthalmic and potential risk factor data were collected, including body mass index (BMI), smoking, alcohol, diabetes, hypertension, analgesics, vitamin supplementation, nutrition, sunlight exposure, dehydration, hormonal (women), blood lipids, glucose, urea, creatinine, uric acid, and vitamin levels.

RESULTS

For waterclefts, univariable analysis identified BMI, alcohol intake, vitamin status, sunlight, urea, creatinine, and uric acid as possible risk factors. Multivariable analysis identified two independent associations. Total number of 'any' analgesics in the previous year: adjusted P<0.01 (U-shaped risk profile, unadjusted high vs medium use (=reference) OR 2.39, 95% CI 1.35-4.26 with medium use vs none (=reference) OR 0.43, 95% CI 0.26-0.72); total sunlight: adjusted P=0.03 (unadjusted highest exposure vs lowest (=reference) OR 3.25, 95% CI 1.11-9.50). For retrodots, univariable analysis identified alcohol, HRT, and lipids. Multivariable analysis identified two independent associations. Mean number of alcohol units consumed per month, adjusted P=0.02 and HDL cholesterol levels, adjusted P=0.02 (unadjusted ORs NS both).

CONCLUSION

This is the first available published information on risk factors for the human cataractous lens features waterclefts and retrodots.

Relationships between ocular dimensions and adult stature among participants in the Reykjavik Eye Study

PURPOSE

To examine the relationships between adult stature, age and ocular dimensions in a large homogenous, white population.

METHODS

We used the national population census for Reykjavik to select a random sample of adults aged 50 years or older. A total of 846 persons were examined. Scheimpflug images were used to measure anterior chamber depth. Ultrasound was used to measure axial length, lens thickness and vitreous chamber depth. An autorefracto-keratometer was used to measure autorefractive and keratometric values, including the radius of the corneal curvature. Stereo fundus photographs were taken of the optic disc and measurements of the disc diameters were made using computer software.

RESULTS

Height correlated positively with axial length in the multivariate model (B = 0.020, 95% CI 0.006-0.034, p < 0.01). Both age and height showed significant correlations with vitreous chamber depth, where the correlation with age was negative (B = - 0.016, 95% CI - 0.006 to - 0.025, p < 0.005) and the correlation with height was positive (B = 0.019, 95% CI 0.005-0.034, p < 0.01). Height also showed a positive correlation with the radius of the corneal curvature (B = 0.008, 95% CI 0.004-0.011, p < 0.001). Anterior chamber depth had a negative correlation with age (B = - 0.013, 95% CI - 0.010 to - 0.016, p < 0.001), whereas lens thickness had a significant positive correlation with age (B = 0.019, 95% CI 0.016-0.023, p < 0.001). We found a significant negative correlation between axial length and refraction/spherical equivalent (r = - 0.595, p < 0.0001).

DISCUSSION

Our results indicate that there is a significant relationship between height and several ocular dimensions in this adult population and confirms a negative correlation between axial length and refraction.

Incidence and Progression of Lens Opacities

BACKGROUND

Hormone replacement therapy (HRT) is associated in cross-sectional studies with a decreased prevalence of lens opacities. We explored the associations of HRT and reproductive factors with the incidence and progression of lens opacities over a 2-year period.

METHODS

Data were derived from 1458 women ages 65 years and older from the Salisbury Eye Evaluation population-based prospective cohort study in Salisbury, MD, 1993-1997.

RESULTS

HRT was not associated with incident nuclear, cortical, or posterior subcapsular opacities, or with progression of nuclear or cortical opacification. Women who had an early menopause had a higher risk of nuclear progression, whereas those who had a later menopause had a lower risk (linear trend P = 0.013). Other variables related to reproduction, such as oral contraceptive use, age at menarche, number of births, and history of hysterectomy, were not associated with any of the outcomes.

CONCLUSIONS

These data suggest no evidence of protection against the incidence or progression of lens opacities with HRT.

Weight status, abdominal adiposity, diabetes, and early age-related lens opacities

BACKGROUND

The association between weight status and the risk of lens opacities has received little attention.

OBJECTIVE

We examined the cross-sectional relations of body mass index (BMI; in kg/m(2)), waist circumference, and diabetes with the presence of age-related lens opacities.

DESIGN

Eye examinations were conducted in 466 Boston-area women aged 53-73 y who were without previously diagnosed cataracts and were part of the Nurses' Health Study cohort. Weight, height, waist, and hip measurements were obtained by self-report. Lens status was evaluated by using the Lens Opacification Classification System III (LOCS III). BMI and waist circumference were used as measures of overweight and abdominal adiposity, respectively. Nuclear, cortical, and posterior subcapsular (PSC) opacities were defined as LOCS III scores > or = 2.5, > or = 1.0, and > or = 0.5, respectively. Diabetes was defined as a history of type 2 diabetes or as a fasting plasma glucose concentration > or = 7.0 mmol/L.

RESULTS

Women with diabetes were significantly more likely to have PSC opacities [odds ratio (OR): 4.1; 95% CI: 1.8, 9.4] than were women with fasting plasma glucose concentrations < 6.1 mmol/L. Women with a BMI > or = 30 had a higher prevalence of PSC opacities than did women with a BMI < 25 (OR: 2.5; 1.2, 5.2), and women with a waist circumference > or = 89 cm had a higher prevalence of PSC opacities than did those with a waist circumference < 80 cm (OR: 2.3; 1.0, 5.2). Diabetes and measures of adiposity were unrelated to the prevalence of cortical and nuclear opacities.

CONCLUSIONS

Diabetes is a strong risk factor for PSC opacities, and overweight and abdominal adiposity may be risk factors for PSC opacities.

Risk factors for nuclear, cortical and posterior subcapsular cataracts in the Chinese population of Singapore: the Tanjong Pagar Survey

AIM

To describe risk factors for nuclear, cortical, and posterior subcapsular (PSC) cataracts in Chinese Singaporeans.

METHODS

A population based cross sectional study was carried out on ethnic Chinese men and women aged 40-81 years. A stratified, clustered, disproportionate (more weights to older people), random sampling procedure was used to initially select 2000 Chinese names of those aged 40-79 years from the 1996 electoral register in the Tanjong Pagar district in Singapore. Eligible subjects (n = 1717) were invited for a standardised ocular examination and interview at a centralised clinic, following which an abbreviated examination was conducted for non-respondents in their homes. Cataract was graded clinically using to the Lens Opacity Classification System (LOCS) III system. The main outcome measures were adjusted odds ratio for risk factors for specific cataract types (nuclear, cortical and PSC), any cataract and cataract surgery, examined in multiple logistic regression models.

RESULTS

Out of the 1232 (71.8%) examined, 1206 (70.2%) provided lens data for this analysis. Increasing age was associated with all cataract types, any cataract, and cataract surgery. There was no significant sex difference in presence of any cataract, specific cataract types or cataract surgery. After controlling for age, sex, and other factors, diabetes was associated with cortical cataract (3.1; 95% CI: 1.6 to 6.1), PSC cataract (2.2; 95% CI 1.2 to 4.1), any cataract (2.0; 95% CI: 0.9 to 4.5), and cataract surgery (2.3; 95% CI: 1.3 to 4.1). Lower body mass index was associated with cortical cataract (1.8; 95% CI: 1.1 to 2.9; lowest versus highest quintile) and any cataract (2.3; 95% CI: 1.3 to 4.0). Current cigarette smoking was associated with nuclear cataract (1.7, 95% CI: 1.0 to 2.9; more than 10 cigarettes per day versus none). A non-professional occupation was associated with nuclear cataract (2.9; 95% CI: 1.5 to 5.8; for production or machine operators and 2.6; 95% CI: 1.2 to 5.5; for labourers or agricultural workers, both versus professionals). Lower education was associated with nuclear cataract (2.3; 95% CI: 1.0 to 5.2, none versus tertiary), while lower household income was associated with PSC cataract (4.7, 95% CI: 1.1 to 20.0; income <S$2000 versus >S$4000).

CONCLUSIONS

Age related cataracts are associated with a variety of risk factors among Chinese people in Singapore, similar to those reported in European, Indian, and African derived populations. These data support common aetiological mechanisms for age related cataracts, irrespective of ethnic origin.

Risk factors for incident nuclear opacities

PURPOSE

To evaluate risk factors for the 4-year incidence of nuclear opacities.

DESIGN

Population-based cohort study (85% participation at 4-year follow-up).

PARTICIPANTS

Two thousand six hundred nine black participants of the Barbados Eye Studies, without any nuclear opacities at baseline.

METHODS

Participants completed a standardized protocol at baseline and follow-up, including ophthalmic and other measurements, an interview, slit-lamp lens grading, fundus photography, and an ophthalmologic examination. Factors associated with the incidence of nuclear opacities (Lens Opacities Classification System II N > or = 2) were evaluated by logistic regression.

MAIN OUTCOME MEASURE

Relative risks (RR) with 95% confidence intervals (95% CI).

RESULTS

The 4-year incidence of nuclear opacities was 9.2% (241 of 2609) and increased greatly with age. Women were at significantly greater risk (RR = 1.8), as were persons with darker iris color (RR = 4.9), myopia (RR = 2.8), history of diabetes (RR = 1.6), leaner body mass (RR = 0.95 for each unit increase in body mass index [kg/m(2)]), and intraocular pressure (IOP)-lowering treatment (RR = 2.7), mainly with topical beta-blockers. Treated participants had a threefold RR of nuclear opacities (RR = 3.2; 95% CI, 1.6, 6.5) compared with those untreated and with IOP < or =21 mmHg. Among participants with IOP >21 mmHg, those receiving treatment (n = 33) had a fivefold RR (RR = 5.0; 95% CI, 1.7, 15.1) versus those who were untreated. The RR was similar for treated persons with and without open-angle glaucoma (RR = 3.1; 95% CI, 1.3, 7.4 and RR = 2.8; 95% CI, 0.9, 8.6 respectively) but was lower in persons with newly detected (and thus untreated) glaucoma at baseline (RR = 1.2; 95% CI, 0.6, 2.6) compared with those without open-angle glaucoma or treatment.

CONCLUSIONS

The 4-year risk of nuclear opacities increased with age, female gender, darker iris color, myopia, diabetes, and leaner body mass, indicating similarities with other populations. The use of topical IOP-lowering medications tripled the RR of nuclear opacities in this study, an association that requires verification from clinical trials.

Risk factors associated with age-related nuclear and cortical cataract : a case-control study in the Age-Related Eye Disease Study, AREDS Report No. 5

OBJECTIVE

To investigate possible risk factors for age-related nuclear and cortical cataracts in participants in the Age-Related Eye Disease Study (AREDS).

DESIGN

Case-control study.

PARTICIPANTS

Of the 4757 persons enrolled in AREDS, 4477 age 60 to 80 years are included in the study.

MAIN OUTCOME MEASURES

Slit-lamp lens photographs were used to classify participants into one of three nuclear opacity groups (moderate nuclear, mild nuclear, and controls), ignoring cortical opacities. Retroillumination lens photographs were used to classify participants into one of three cortical opacity groups (moderate cortical, mild cortical, and controls), ignoring nuclear opacities.

RESULTS

Persons with moderate nuclear opacities were more likely to be female, nonwhite, and smokers and to have large drusen. Moderate nuclear opacities were less common in persons with higher educational status, a history of diabetes, and among those taking nonsteroidal antiinflammatory drugs. Moderate cortical opacities were associated with dark iris color, large drusen, weight change, and, at a borderline level of significance, higher levels of sunlight exposure and use of thyroid hormones. Moderate cortical opacities were less common in persons with higher educational status.

CONCLUSION

Consistent findings have now been reported across many studies for gender, educational status, sunlight exposure, and smoking. Our findings that use of nonsteroidal antiinflammatory drugs is inversely associated with nuclear cataract and that dark iris color and use of thyroid hormones may increase cortical cataract risk are less well substantiated and require further investigation.

Relations of body fat distribution and height with cataract in men

BACKGROUND

Cataract is the leading cause of blindness worldwide. Body mass index (BMI; in kg/m(2)) is a risk factor for cataract, but other anthropometric measurements may also be important.

OBJECTIVE

We tested relations of alternative measures of body size, including height and waist-to-hip ratio (WHR), as well as BMI, with cataract.

DESIGN

This was a prospective follow-up study. We analyzed data from 20271 participants in the Physicians' Health Study who did not have cataract at baseline and for whom there was complete information on weight, height, and other risk factors. For analyses concerning WHR, we excluded 3121 additional men for whom we did not have these measurements, assessed at the ninth year of follow-up. The main outcome measures were incident cataract and cataract surgery.

RESULTS

Among the 17150 men for whom there were complete data, we confirmed an incident cataract in 1727 during an average of 14 y of follow-up. In proportional hazards regression models that adjusted for many known or suspected risk factors, higher BMI [rate ratio (RR) = 1.25 for >/=27.8 compared with <22, P: for trend = 0. 03], height (RR = 1.23 for >/=184 cm compared with </=170 cm, P: for trend = 0.02), and WHR (RR = 1.31 for top compared with bottom quintile, P: for trend = 0.003) were each independently associated with incident cataract.

CONCLUSIONS

In addition to BMI, both height and abdominal adiposity are independent risk factors for cataract. These relations are biologically plausible and, if causal, suggest that prevention of obesity and beneficial lifestyle changes resulting in weight loss and reduction of central obesity would lessen the incidence and costs of cataract.