Associations between plasma levels of vitamins and cataract in the Italian-American Clinical Trial of Nutritional Supplements and Age-Related Cataract (CTNS): CTNS Report #2

PURPOSE: To investigate the association at baseline between plasma levels of selected vitamins and the presence and type of cataract in the participants in The Italian-American Trial of Nutritional Supplements and Age-related Cataract. METHODS: At baseline, the participants (1020, 710 with "early cataract" and 310 with "no cataract," 55-75 years of age) received an ocular examination, photographic lens grading, and measurement of plasma levels of vitamins A, C, E, beta-carotene, and of red blood cell glutathione reductase activity. RESULTS: In multiple logistic models adjusted for potential confounders, high vitamin C levels were associated with a protective effect on nuclear (N) [OR: 0.54; 95% CI: 0.30, 0.97] and posterior subcapsular (PSC) cataract (OR: 0.37; 95% CI: 0.15, 0.93). High vitamin E levels were associated with increased prevalence of cortical cataract (C) (OR: 1.99; 95% CI: 1.02-3.90), PSC (OR: 3.27; 95% CI: 1.34, 7.96) and of any cataract (OR: 1.86; 95% CI: 1.08, 3.18). Conclusions: In agreement with some earlier studies, we found higher plasma levels of vitamin C to be associated with reduced prevalence of N and PSC cataracts. The finding of an increased prevalence of some types of cataract with higher levels of vitamin E was unexpected, has not been previously reported, and could be due to unadjusted confounding.     

Serum 25-hydroxyvitamin D and Age-Related Cataract

Purpose: Cataract and insufficient vitamin D intake are both increasing worldwide concerns, yet little is known about the relationship between serum 25-hydroxyvitamin D (25(OH)D) levels and age-related cataract. We performed this study to determine the association between serum 25(OH)D levels and age-related cataract in adults.

Methods: Study participants comprised 16,086 adults aged 40 years or older who had never been diagnosed with or undergone surgery for cataract using Korean National Health and Nutrition Examination Survey data from 2008 to 2012. Participants were assessed to have cataract when diagnosed with cortical, nuclear, anterior subcapsular, posterior subcapsular, or mixed cataract. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the magnitude and significance of the association between serum 25(OH)D levels and cataract in multivariable logistic regression models.

Results: The OR for nuclear cataract with the highest quintile of serum 25(OH)D levels was 0.86 (95% CI 0.75–0.99) compared to the lowest quintile. A linear trend across quintiles was significant. Natural log-transformed serum 25(OH)D levels were also significantly associated with nuclear cataract (OR 0.84, 95% CI 0.75–0.95). The opulation-attributable fraction of nuclear cataract due to serum 25(OH)D insufficiency (<30 ng/mL) was 8.8% (p = 0.048).

Conclusions: Serum 25(OH)D levels were inversely associated with the risk of nuclear cataract. Prospective studies investigating the effects of serum 25(OH)D levels on the development of nuclear cataract are needed to confirm our findings.     

Prevalence of Lens Opacities in Asian Malays

Purpose: To describe the prevalence of lens opacities and cataract surgery in an older Malay population in Singapore.

Methods: The Singapore Malay Eye Study is a population-based cross-sectional study of 3280 (78.7% response rate) Malay adults aged 40–80 years. Participants underwent a standardized clinical eye examination. Digital slit-lamp and retroillumination photographs were taken of both eyes of each participant and graded for age-related nuclear, cortical and posterior subcapsular (PSC) cataract, following the Wisconsin Cataract Grading System. Other lens opacities, including retrodots and vacuoles, were also graded. Information on medical and lifestyle factors was collected using questionnaires. The study sample was directly age-standardized to the Malay population in Singapore using the 2000 Singapore population census.

Results: A total of 3054 (97.7%) and 3113 (99.6%) participants had gradable Topcon slit lamp and Neitz photographs, respectively. The overall age-adjusted prevalence of any cataract was 29.1%, and that of nuclear, cortical and PSC cataract were 12.9% (95% confidence interval, CI, 11.2–13.1%), 21.2% (95% CI 19.8–22.7%) and 9.7% (95% CI 8.8–10.8%), respectively. Age-adjusted prevalence of cataract surgery was 4.7% (95% CI 4.2–5.4%). Prevalence of all three cataract types and cataract surgery increased with age. Age-adjusted prevalence for retrodots and vacuoles were 19.7% (95% CI 18.3–21.1%) and 64.3% (95% CI 61.1–67.6%), respectively. Retrodots were found to be associated with prevalence of all three cataract types, while vacuoles were associated with cortical and PSC cataract prevalence.

Conclusion: Lens opacities were common in this urban Malay population. Retrodots and vacuoles were found to be associated with age-related cataract.     

Lens retrodots and vacuoles and their associations with the prevalence and incidence of age-related cataract

Aim

To assess the prevalence of retrodots and vacuoles and their associations with the prevalence and long-term incidence of age-related cataract in an older Australian cohort.

Methods

Of 3654 baseline participants of the Blue Mountains Eye Study aged 49+ years (1992–1994), 2335 and 1952 were re-examined after 5 and 10 years, respectively. Lens photographs were graded for cataract, retrodots, and vacuoles. Eye-specific data were used to assess the associations between retrodots or vacuoles at baseline and the prevalence and 10-year incidence of nuclear, cortical, and posterior subcapsular (PSC) cataract and cataract surgery.

Results

At baseline, retrodots were present in 142 persons (4%) and vacuoles in 1333 persons (40%). Prevalence of both lens features increased with increasing age (Pfor trend <0.0001). After adjusting for age and gender, vacuoles were associated with prevalent PSC cataract at baseline (odds ratio (OR), 1.60, 95% confidence interval (CI), 1.25–2.05). After adjusting for age, gender, smoking, hypertension, diabetes, education, and use of inhaled/oral steroids, baseline retrodots were associated with an increased incidence of cataract surgery (OR 2.90, 95% CI 1.71–4.91), while 3+ vacuoles at baseline were associated with an increased risk of PSC cataract (OR 3.56, 95% CI 2.13–5.95) and cataract surgery (OR 1.84, 95% CI 1.22–2.77).

Discussion

Lens retrodots and vacuoles were found to be positively associated with 10-year incidence of cataract surgery, and vacuoles associated with PSC cataract, a finding suggestive of shared risk factors or pathogenesis between these two lens features and the development of PSC cataract.     

Association between metabolic syndrome and age-related cataract

AIM: To determine the effect of metabolic syndrome on age-related cataract formation.METHODS: We analyzed data for 2852 subjects [41.8% men and 58.2% women; mean (±SD) age, 52.9±13.9y], taken from the Korea National Health and Nutrition Examination Survey 2008. Metabolic syndrome was diagnosed by criteria proposed by the Joint Interim Societies. Cataract was diagnosed by using the Lens Opacities Classification System III. The association between metabolic syndrome and cataract was determined using age-adjusted and multivariable logistic regression analyses. RESULTS:In multivariable analyses, men with metabolic syndrome had a 64% increased risk of nuclear cataract [odds ratio (OR), 1.64; 95% confidence interval (CI), 1.12-2.39]. Women with metabolic syndrome had a 56% increased risk of cortical cataract (OR, 1.56; 95% CI, 1.06-2.30). Men and women with metabolic syndrome had a 46% (OR, 1.46; 95% CI, 1.01-2.12) and 49% (OR, 1.49; 95% CI, 1.07-2.08) increased risk of any cataract, respectively. The prevalence of nuclear and any cataract significantly increased with an increasing number of disturbed metabolic components in men, and prevalence of all types of cataracts increased in women. Men using hypoglycemic medication had an increased risk of nuclear (OR, 2.62; 95% CI, 1.41-4.86) and any (OR, 2.27; 95% CI, 1.14-4.51) cataract, and women using antidyslipidemia medication had an increased risk of cortical (OR, 2.18; 95% CI, 1.12-4.24) and any (OR, 2.21; 95% CI, 1.14-4.26) cataract.CONCLUSION: Metabolic syndrome and its components, such as abdominal obesity, high blood pressure, and impaired fasting glucose, are associated with age-related cataract formation in the Korean population.     

Association between Cataract and Keratinocytic Skin Cancers or Melanoma: Speculating on the Common Role of Sun and Ultraviolet Radiation Exposures

Purpose: Cataract and sun-related skin conditions are proxies to lifetime UV exposure. We examined the association between them using real-world data from an unselected Israeli population.

Methods: Computerized data was obtained from an Israeli health maintenance organization regarding cases of sun-related skin pathologies and cataract diagnosed between 2006 and 2011 in 686,260 members aged 40 or above.

Results: Sun-related skin disorders were found in 9.3% of the study population, more commonly among the elderly, and those who reside in areas of higher socioeconomic status. Cataract was diagnosed in 13.1% of the study population, with highest prevalence (47%) among squamous cell carcinoma patients, who were the oldest group. Multivariable analysis adjusting for age, sex, residential district, birth region, smoking, and chronic comorbidities showed no statistically significant association between melanoma and cataract (OR = 1.06; 95% CI: 0.91–1.22). Basal cell carcinoma, squamous cell carcinomas, and actinic keratosis were associated with increased likelihood of prevalent cataract with adjusted odds ratios (95% CI) of 1.14 (1.08–1.20), 1.11 (1.01–1.19), and 1.16 (1.13–1.19), respectively. When stratified by gender, the association between actinic keratosis and cataract was stronger in women than in men, particularly in patients under 65 years.

Conclusions: The association between the prevalence of skin cancers and the prevalence of cataract enhances the conclusion that cataract is related to UVR exposure.     

Prevalence and associations of cataract in a rural Chinese adult population: the Handan Eye Study

Background

Cataract remains the leading cause of blindness and visual impairment in the world and in China. However, data on the prevalence of cataract based on standardized lens grading protocols from mainland China are limited. This paper estimated the age- and gender-specific prevalence and risk factor for cataract

Methods

In a population-based Chinese sample, participants underwent a comprehensive ophthalmic examination, including assessment of cortical, nuclear, posterior subcapsular (PSC) and mixed lens opacities from slit-lamp grading using the Lens Opacities Classification System III.

Results

Of the 7,557 eligible subjects, 6,830 took part in the study (90.4?% response rate), and 6,544 participants (95.8?%, mean age 52.0?±?11.8 years) had lens data for analyses. The prevalence of any cataract surgery in at least one eye was 0.8?% (95?% confidence interval [CI], 0.62, 1.06), with similar rates between men and women. The overall prevalence of any cataract or cataract surgery was 20.8?% (95?% CI, 19.8, 21.8), higher in women than in men after adjusting for age (23.6?% vs 17.6?%; OR: 1.78; 95?% CI: 1.54–2.07). When distinct lens opacity was categorized in each eye as cortical, nuclear, PSC or mixed, based on one randomly selected eye, cortical cataract was the most common distinct subtype (12.3?%), followed by mixed (3.2?%), nuclear (1.7?%), and PSC (0.2?%) cataract. The prevalence of all lens opacities increased with age (P?<?0.001). After excluding other causes for visual impairment, the proportion of people with best corrected visual acuity <20/60 was 21?% among those with PSC, and 12?% among those with mixed opacities in the better-seeing eye. In multivariable logistic regression models, myopia was associated with all cataract types, while higher fasting plasma glucose and diabetes were only associated with PSC cataract.

Conclusions

Cataract affects 20?% of the population aged 30 years and older living in rural China, with cortical cataract the most common subtype. Risk factors for cataract include myopia and diabetes.     

Cataract and its surgery in Papua New Guinea

PURPOSE: To determine the prevalence of visually significant cataract, unoperated blinding cataract, and cataract surgery for those aged 50 years and over in Papua New Guinea. Also, to determine the characteristics, rate, coverage and outcome of cataract surgery, and barriers to its uptake. METHODS: Using the World Health Organization Rapid Assessment of Cataract Surgical Services protocol, a population-based cross-sectional survey was conducted in 2005. By two-stage cluster random sampling, 39 clusters of 30 people were selected. Each eye with a presenting visual acuity worse than 6/18 and/or a history of cataract surgery was examined. RESULTS: Of the 1191 people enumerated, 98.6% were examined. The 50 years and older age-gender-adjusted prevalence of cataract-induced vision impairment (presenting acuity less than 6/18 in the better eye) was 7.4% (95% confidence interval [CI]: 6.4, 10.2, design effect [deff] = 1.3). That for cataract-caused functional blindness (presenting acuity less than 6/60 in the better eye) was 6.4% (95% CI: 5.1, 7.3, deff = 1.1). The latter was not associated with gender (P = 0.6). For the sample, Cataract Surgical Coverage at 6/60 was 34.5% for Eyes and 45.3% for Persons. The Cataract Surgical Rate for Papua New Guinea was less than 500 per million population per year. The age-gender-adjusted prevalence of those having had cataract surgery was 8.3% (95% CI: 6.6, 9.8, deff = 1.3). Vision outcomes of surgery did not meet World Health Organization guidelines. Lack of awareness was the most common reason for not seeking and undergoing surgery. CONCLUSION: Increasing the quantity and quality of cataract surgery need to be priorities for Papua New Guinea eye care services.     

Cataract surgery reduces subjective visual disability

Purpose: The present study examines the impact of cataract on visual disability (VD) and how cataract surgery alters VD. Methods: Fifty-six patients were assessed pre- and at 3 months post-cataract surgery. Cataract severity was measured with the Lens Opacities Classification System ill (LOCS III). Visual disability was assessed by questionnaire. The relationship between LOCS III scores and total VD score was examined with linear regression. Repeated measures analysis of variance was used to determine whether the pre- and postoperative VD scores were different. Results : The VD score was found to relate more closely to the LOCS III score in the least affected eye than in the most affected eye. The VD score is related to nuclear opacity (P=0.01), and posterior subcapsular cataract (PSC; P=0.0004), but not to cortical cataract (P=0.51) (r²= 0.43). The VD score is significantly greater before surgery (mean ±SD) 1.81 +0.67) than after (1.19 ± 0.21; P± 0.001). Conclusions: Nuclear and PSC cataracts cause more visual disability than cortical cataracts. Visual disability is significantly reduced by cataract surgery.     

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.     

Cataract and its surgery in Fiji

Background: To characterize cataract and its surgery among adults aged ≥40 years in Fiji. Design: Population‐based cross‐sectional survey using multistage cluster random sampling. Participants: 1381 (= 73.0% participation); eight provinces on Viti Levu. Methods: Interview‐based questionnaire; visual acuity measured; autorefraction; dilated ocular examination. Main Outcome Measures: Prevalence; predictors; surgical outcomes. Results: Being Indian (P = 0.001), elderly (P < 0.001), and previous/current smoker (P = 0.036) were predictive of at least one unoperated vision‐impairing or operated cataract. Gender (P = 0.062) and diabetes (P = 0.384) were not. Unoperated cataract (predominantly nucleosclerosis) was the second most frequent (25.0%) cause of low vision (<6/18, ≥6/60) and commonest (71.1%) of blindness (<6/60). Ethnicity‐gender‐age‐domicile adjusted and extrapolating to the Fiji population aged ≥40 years, prevalence of cataract‐induced low vision and blindness were each 1.7% (95% confidence interval [CI] 1.0–2.4%). At least one eye of 4.6% and both of 1.8% participants had surgery (86.4% extracapsular). Gender (P = 0.213), age (P = 0.472) and rural/urban domicile (P = 0.895) were not predictors of surgery among those who required it in at least one eye. After intraocular lens surgery: 50.7% had pupillary posterior capsular opacification; mean spherical equivalent was ?1.37 ± 1.95D (range, ?6.38 to +2.25D); mean cylindrical error was 2.31 ± 1.75D (range, 0.0 to 8.75D); ≥N8 for 39.5%; ≥6/18 for 56.6%; <6/60 for 19.7%, with 2.6% no light perception. Ethnicity‐gender‐age‐domicile adjusted and extrapolating to the Fiji population aged ≥40 years, Cataract Surgical Coverage (Person) was 47.5% (95%CI 29.2–65.8%) at <6/18, and 65.2% (95%CI 37.8–92.6%) at <6/60. Conclusions: Fiji cataract services and outcomes compare favourably with those of neighbouring Papua New Guinea and Timor Leste.     

Cataract in indigenous Australians: the National Indigenous Eye Health Survey

Background: To determine the prevalence of vision loss due to cataract in indigenous Australians. Methods: A national, stratified, random cluster sample was selected in 30 communities across Australia. Data collection was undertaken in 2008. Adults 40 years and older were examined using a standardized protocol that included a questionnaire. The presence of visually significant cataract was assessed. Results: Response rates were good and 1189 indigenous adults were examined and overall recruitment was 72%. Low vision (<6/12–6/60) due to cataract occurred in 2.52% (1.63–3.41%) and blindness (<6/60) in 0.59% (95% CI: 0.24–1.21%). The cataract coverage rate (proportion of those with visually significant cataract who had been operated on) was 65.3% (95% CI: 55.0–74.6%). Projections suggest that there are 3234 indigenous adults with vision loss from cataract. Conclusions: Cataract remains a major cause of vision loss in Aboriginal and Torres Strait Islander peoples. There were no significant regional or state differences in the prevalence of cataract or of cataract surgical coverage, which suggests that increased cataract surgery services are required across the country to address cataract in indigenous Australians.     

Reasons for Refusing Cataract Surgery in Illiterate Individuals in a Tribal Area of Andhra Pradesh,India

Purpose: To assess the reasons for refusing cataract surgery in illiterate individuals in a tribal area of India.

Methods: A prospective study evaluated 1046 subjects who had undergone screening in eye camps and included 398 of 492 referred subjects with cataract who refused to seek cataract surgery. Subjects were assessed to elicit general and specific reasons for non-compliance. Multiple logistic regression analysis was applied to determine the associations; p?Results: Overall, 83% (329/398) of subjects reported that they could manage with their current vision. The five most common reasons they did not proceed with cataract surgery were: fear of losing current vision, work priority, lack of support systems, a dependency due to old age, and expenses required after surgery. Odds of seeking treatment were lower among unemployed subjects (odds ratio, OR, 0.4, 95% confidence interval, CI, 0.19–0.86; p?=?0.01) and in patients with family income <1000 Indian rupees per month (OR 0.5, 95% CI 0.34–0.94; p?=?0.02), and higher among those unilaterally blind (OR 10.8, 95% CI 3.3–35.6; p?≤?0.01).

Conclusion: In a tribal setting, 83% of individuals referred for cataract surgery did not proceed with surgery. Reasons given for non-compliance were not directly related to the surgery but focused on valid day-to-day difficulties anticipated to increase following surgery. Beyond accessibility and cost of surgery, other social and infrastructural factors need to be addressed to increase the uptake of cataract surgery.     

Relationship between dietary macronutrient intake and the risk of age-related cataract in middle-aged and elderly patients in northeast China

AIM: To examine the association between dietary macronutrient intake and the risk of age-related cataract (ARC) in middle-aged and elderly men.METHODS:A hospital-based case-control study was conducted from December 2009 to November 2011. Cases (n=360) were patients with cataract aged 45-85 years old, and controls (n=360) were patients who had been admitted to the same hospital for diseases not related with cataract. All subjects were interviewed using a structured interviewer-administrated questionnaire that included information on socio-demographic characteristics, lifestyle habits and detailed medical history, simultaneously, the dietary intakes of nutrients were collected via a valid semi-quantitative food frequency questionnaire (FFQ). The odds ratios (OR) and corresponding 95% confidence intervals (CI) of three types of ARC were estimated using multiple logistic regression models.RESULTS: After adjusting for multiple potential confounders, total dietary intake of carbohydrate was positively associated with cortical cataract, compared to controls in the lowest quartile, and the OR for cases in the highest quartile of intake was 2.471 (95%CI:1.348-6.043, P=0.027). Higher dietary intakes of protein were protective for posterior subcapsular cataract (PSC) (OR=0.528, 95%CI:0.148-0.869, P=0.023). Dietary fat intake was not associated with any type of cataract, however, participants in the highest quartile of polyunsaturated fatty acids intake had 2.7 times the risk of nuclear cataract as did those in the lowest quartile (OR=2.742, 95%CI:1.790-4.200, P=0.033).CONCLUSION: A high intake of carbohydrate and polyunsaturated fatty acid may increase the odds of cortical and nuclear cataract, respectively, whereas high intake of protein, especially animal protein, may protect against PSC cataract. It is possible that dietary changes of target population may reduce the risk of ARC.     

Rapid Assessment of Avoidable Blindness and Cataract Surgical Services in Kilimanjaro Region,Tanzania

Purpose: To estimate the prevalence and causes of avoidable blindness and visual impairment in persons 50 years of age and older, and to assess the impact of cataract surgical services.

Methods: In this cross-sectional population-based survey, 72 clusters of 50 people 50 years and older were selected by probability proportionate to size sampling. Households within clusters were selected through compact segment sampling. Participants underwent an ophthalmic examination in their homes, including measurement of visual acuity (VA) with a tumbling-E chart and diagnosis of the principal cause of visual impairment. Patients who had been operated on were questioned about details of their cataract surgery.

Results: Three thousand six hundred eligible subjects were selected, of whom 3,436 (95.5%) were examined. The prevalence of bilateral blindness (presenting VA < 3/60) was 2.4% (95% confidence interval [CI], 1.9%–2.9%); prevalence of severe visual impairment was 0.99% (95% CI, 0.98%–0.99%); and prevalence of visual impairment (VA of <?6/18 and ≥ 6/60) was 5.4% (95% CI, 4.6%–6.2%) in the sample. Unoperated cataract accounted for 52.4% of blindness and 70.6% of severe visual impairment. Cataract surgical coverage among people at 3/60 was 68.9%. Overall, 58.6% and 69.6% of the 191 eyes that had undergone cataract surgery had VA greater than or equal to 6/18 with available correction and best correction respectively.

Conclusions: The prevalence of blindness in this population in Kilimanjaro Region was low, reflecting high cataract surgical coverage from an outreach program. Even with high cataract surgical coverage, cataract remains the leading cause of vision loss and an emphasis on quality is needed.     

Prevalence and Visual Risk Factors for Falls in Bilateral Cataract Patients in Ho Chi Minh City,Vietnam

Abstract

Purpose: To determine the prevalence of falls in the 12 months prior to cataract surgery and examine the associations between visual and other risk factors and falls among older bilateral cataract patients in Vietnam.

Methods: Data collected from 413 patients in the week before scheduled cataract surgery included a questionnaire and three objective visual tests.

Results: The outcome of interest was self-reported falls in the previous 12 months. A total of 13% (n?=?53) of bilateral cataract patients reported 60 falls within the previous 12 months. After adjusting for age, sex, race, employment status, comorbidities, medication usage, refractive management, living status and the three objective visual tests in the worse eye, women (odds ratio, OR, 4.64, 95% confidence interval, CI, 1.85–11.66), and those who lived alone (OR 4.51, 95% CI 1.44–14.14) were at increased risk of a fall. Those who reported a comorbidity were at decreased risk of a fall (OR 0.43, 95% CI 0.19–0.95). Contrast sensitivity (OR 0.31, 95% CI 0.10–0.95) was the only significant visual test associated with a fall. These results were similar for the better eye, except the presence of a comorbidity was not significant (OR 0.45, 95% CI 0.20–1.02). Again, contrast sensitivity was the only significant visual factor associated with a fall (OR 0.15, 95% CI 0.04–0.53).

Conclusion: Bilateral cataract patients in Vietnam are potentially at high risk of falls and in need of falls prevention interventions. It may also be important for ophthalmologists and health professionals to consider contrast sensitivity measures when prioritizing cataract patients for surgery and assessing their risk of falls.     

Fasting blood glucose levels and the long‐term incidence and progression of cataract – the Blue Mountains Eye Study

Purpose: To assess the associations between fasting blood glucose and the long‐term incidence and progression of cataract. Methods: A total of 3654 persons aged 49+ years were examined at baseline with fasting blood glucose measured, and 2454 re‐examined after 5 and/or 10 years. Lens photographs from each visit were used to assess cataract incidence and progression. Associations between baseline fasting blood glucose and incidence and progression of cortical, nuclear and posterior subcapsular (PSC) cataract were assessed using discrete logistic regression and change‐point models. Results: After adjusting for potential confounders, baseline fasting blood glucose was associated with the 10‐year incidence of cortical cataract with a threshold at blood glucose level of 6.0 mm (odds ratio [OR] 1.79, 95% confidence interval [CI] 1.25–2.57 for fasting glucose ≥6.0 mm compared to fasting glucose <6.0 mm). Each 1.0 mm increase in fasting glucose was also associated with higher 5‐year progression of PSC (OR 1.25, 95% CI: 1.15–1.35), 10‐year progression of cortical (OR 1.14, 95% CI: 1.01–1.27) and nuclear (OR 1.20, 95% CI: 1.01–1.43) cataract, with no thresholds detected. Conclusions: In this primarily nondiabetic older population, baseline fasting blood glucose was associated with the long‐term incidence of cortical cataract and long‐term progression of all three cataract subtypes.     

The potential role of nutrition on lens pathology: a systematic review and meta-analysis

Oxidative stress is one of the main mechanisms of lens opacification, and certain nutritional antioxidants are suspected to have a protective effect. To examine the role of these nutritional antioxidants on cataract prevention, we searched major databases and reviewed current evidence regarding the protective effect of nutritive antioxidants. We included observational studies that investigate the association between one or more of the following micronutrients and cataract: vitamin A, vitamin C, vitamin E, lutein, zeaxanthin, α- and β-carotene. Two independent authors extracted data and assessed their quality. We pooled results for overall cataract incidence for all types of cataract and separately for nuclear, cortical, and posterior subcapsular cataract. We did not perform sensitivity analysis. Twenty-five studies were included in the qualitative and 24 in the quantitative part of the study, with a total of 295,821 participants over 30 years old. Results from pooled analysis showed a protective effect of antioxidants on cataract, but not all of them reached statistical significance. Statistically significant results were reached for vitamin C (odds ratio [OR] = 0.88, 95% confidence interval [CI] [0.81, 0.97]), beta-carotene (OR = 0.89, 95% CI [0.83, 0.95]), and lutein and zeaxanthin (OR = 0.92, 95% CI [0.85, 0.99]). We did not find statistically significant results for vitamin E (OR = 0.84, 95% CI [0.70, 1.01]), vitamin A (OR = 0.90, 95% CI [0.80, 1.00]), or alpha-carotene (OR = 0.92, 95% CI [0.85, 1.00]). The present study shows a relation between certain antioxidants and cataract, but further studies, especially interventional, are needed to confirm this hypothesis.     

Prevalence and Causes of Visual Impairment and Blindness in Adults Aged 45 Years and Older from Parintins: The Brazilian Amazon Region Eye Survey

Purpose: To determine the prevalence and causes of visual impairment and blindness in adults aged 45 years and older from Parintins, Brazilian Amazon Region.

Methods: A random cluster sampling method was used to identify subjects 45 years of age and older from urban and rural census sectors of Parintins city, Amazonas State, from March 2014 to May 2015. Participants underwent a detailed ocular examination, including presenting (PVA) and best corrected visual acuity (BCVA). The main cause of PVA<20/32 per eye was determined.

Results: A total of 2384 subjects were enumerated and 2041 (85.6%) examined. The prevalence of presenting mild visual impairment – MiVI (<20/32 – ≥20/63) in the better-seeing eye was 17.0% [95% CI: 15.3–18.7%], and 8.5% [95% CI: 7.3–9.7%] with best correction. The prevalence of presenting moderate visual impairment – MVI (<20/63 – ≥20/200) was 18.4% [95% CI: 16.2–20.6%], and 6.9% [95% CI: 5.8–8.0%] with best correction. The prevalence of presenting bilateral VA <20/200 was 4.3% [95% CI: 3.6–5.0%], and 3.3% [95% CI: 2.5–4.0%] with best correction and increased with older age. Cataract (47.8%) and glaucoma (7.5%) were its main causes. In less severely affected eyes, uncorrected refractive errors (MVI: 42.6%; MiVI: 79.0%), cataract (MVI: 40.6%; MiVI: 13.7%) and pterygium (MVI: 7.6%; MiVI: 2.7%) were the main causes.

Conclusions: Most cases of visual impairment in Parintins are either preventable or treatable, and public health initiatives should target cataract surgical services and refraction with spectacle provision.     

Cataract in Central Sri Lanka: Prevalence and Risk Factors from the Kandy Eye Study

Purpose:?To estimate the prevalence of and risk factors for cataracts in the Kandy District of central Sri Lanka.

Methods:?A population-based, cross-sectional ophthalmic survey of the inhabitants of rural villages in central Sri Lanka was conducted; 1375 individuals participated (79.9%; age >/= 40 years, average age 57) and 1318 (95.9%) had an examinable lens in at least one eye. Data collection included district, age, occupation, education level, smoking history, height, weight and dilated lens assessment using Lens Opacities Classification System III grading: nuclear (≥4), cortical (≥2) and posterior subcapsular (≥2) cataracts. Aphakic and pseudophakic eyes were included as operated cataracts for statistical analysis.

Results:?The prevalence of any cataract including operated eyes was 33.1% (95% Confidence Interval (CI), 22.4–43.7%): 26.0% cortical; 7.9% posterior sub-capsular and 4.5% nuclear cataracts. No significant association was found between cataract and gender, smoking or outdoor occupation. Low level of education (secondary or higher vs no education: Odds Ratio (OR) 0.6, CI 0.4-0.9, P?=?0.04) and shorter stature were associated with a higher likelihood of any cataract (OR 1.7, CI 1.1-2.7, P??=?0.02).

Conclusions:?The overall prevalence of cataract in central Sri Lanka is similar to that in other developing Asian regions except for the unusually low prevalence of nuclear cataract. Illiteracy and height appear to be significant predictors for cataract in this population and further investigation is required to explore their influence.