Risk Of Age-related Cataract Research Articles

Association of OGG1 and MTHFR polymorphisms with age-related cataract: A systematic review and meta-analysis.

PurposeTo discern and confirm genetic biomarkers that help identify populations at high risk for age-related cataract (ARC).MethodsA literature search was performed in the PubMed, Web of Science and China National Knowledge Internet databases for genetic association studies published before June 26, 2016 regarding ARC susceptibility. All genetic polymorphisms reported were systematically reviewed, followed by extraction of candidate genes/loci with sufficient genotype data in ≥3 studies for the meta-analysis. A random/fixed-effects model was used to calculate the pooled odds ratios and 95% confidence intervals to evaluate the associations considering multiple genetic models. Sensitivity analysis was also performed.ResultsA total of 144 polymorphisms in 36 genes were reported in the 61 previous genetic association studies. Thereby, three polymorphisms of two genes (8-oxoguanine DNA glycosylase-1 [OGG1]; methylenetetrahydrofolate reductase NADPH [MTHFR]) in eight studies were included in the meta-analysis. Regarding the OGG1-rs1052133, the GG (OR = 1.925; 95%CI, 1.181–3.136; p = 0.009) and CG (OR = 1.384; 95%CI, 1.171–1.636; p<0.001) genotypes indicated higher risk of ARC. For the MTHFR gene, the CC+TT genotype of rs1801133 might be protective (OR, 0.838; 95%CI, 0.710–0.989; p = 0.036), whereas the AA+CC genotype of rs1801131 indicated increased risk for the mixed subtype (OR = 1.517; 95%CI, 1.113–2.067; p = 0.008).ConclusionsPolymorphisms of OGG1 and MTHFR genes are associated with ARC susceptibility and may help identify populations at high risk for ARC.

Associations of PARP-1 variant rs1136410 with PARP activities, oxidative DNA damage, and the risk of age-related cataract in a Chinese Han population: A two-stage case-control analysis

ObjectiveTo investigate whether a single nucleotide polymorphism (SNP) rs1136410 in the poly (ADP-ribose) polymerase-1 (PARP-1) gene was associated with PARP activities, 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels, and the risk of age-related cataract (ARC) in a Chinese Han population. MethodsIn this two-stage case-control study with a total of 1010 ARC patients and 1045 controls, SNP rs1136410 was genotyped by high-resolution melting analyses (HRM). PARP activities and 8-OHdG levels in peripheral blood mononuclear cells (PBMCs) were determined by ELISA kits. ResultsIn discovery, replication, and their merged sets, the variant genotypes (AG+GG) of SNP rs1136410 were significantly associated with an increased risk of ARC under a dominant model (Adjusted odds ratio (OR)=1.42, Padj=0.001 for the merged set). This association was further identified in subtype analyses for cortical ARC (Adjusted OR=1.69, Padj<0.001). In subgroup analyses, we identified a significant interaction between SNP rs1136410 and smoking habit in increasing ARC risk (Pinter=0.019). Moreover, ARC patients had lower activities of PARP and higher levels of 8-OHdG than controls. There were significant correlations of SNP rs1136410 with decreased PARP activities and increased 8-OHdG levels in controls and patients with cortical ARC. ConclusionsThis study suggests that SNP rs1136410 may confer susceptibility to ARC by affecting PARP activities and oxidative DNA damage.

Association between polymorphisms of OGG1, EPHA2 and age-related cataract risk: a meta-analysis.

BackgroundEvidences have identified the correlation of 8-oxoguanine DNA glycosylase-1 (OGG1) and eph-receptor tyrosine kinase-type A2 (EPHA2) polymorphisms in age-related cataract (ARC) risk. However, the results were not consistent. The objective of this study was to examine the role of these two gene polymorphisms in ARC susceptibility.MethodsEligible case–control studies published between January 2000 and 2015 were searched and retrieved in the electronic databases. The odds ratio with 95 % confidence interval (CI) was employed to calculate the strength of the relationship.ResultsWe totally screened out six articles, including 5971 cataract patients and 4189 matched controls. Three variants were contained (OGG1 rs1052133; EPHA2 rs7543472 and rs11260867). For OGG1 rs1052133, we detected a significant correlation between OGG1 polymorphism and ARC risk under the heterogenous model (CG vs. CC: OR = 1.34, 95 % CI = 1.06–1.70, P = 0.01) and dominant model (GG+CG vs. CC: OR = 1.45, 95 % CI = 1.16–1.81, P = 0.001), especially in patients with cortical cataract of subgroup analysis by phenotypes (P < 0.05). For EPHA2 rs7543472 and rs11260867, we did not find a positive association between these two mutations and ARC susceptibility in total cases. Subgroup analysis by phenotypes of cataract showed that only in cortical cataract, genotypes of rs7543472 under the allele model, homogenous model and recessive model; genotypes of rs11260867 under the heterogenous model and dominant model were associated with ARC risk.ConclusionsOGG1 rs1052133 (CG and CG+GG genotypes) might be risk factor for ARC, particularly in cortical cataract risk. EPHA2 rs7543472 (T allele and TT genotype) and rs11260867 (CG and GG+CG genotypes) might be associated with cortical cataract.

Tea and Risk of Age-Related Cataracts: A Cross-Sectional Study in Zhejiang Province, China.

BackgroundThe antioxidant properties of tea extracts are considered to be effective in protecting against cataracts. However, there is still insufficient epidemiological knowledge about the protective effects of different types of tea on age-related cataracts.MethodsThe data was derived from the Zhejiang Major Public Health Surveillance (ZJMPHS) Program on health and related factors in the elderly. The relationships between consumption of different types of tea and risk of age-related cataracts were assessed after adjusting for related covariates.ResultsThe prevalence of age-related cataracts in this study population was 4.4% (409/9343). After adjustment for potential confounders, tea drinking was associated with reduced risk of age-related cataracts (adjusted odds ratio [OR] 0.65; 95% confidence interval [CI], 0.47–0.91). Compared to nondrinkers, green tea drinkers had a significantly reduced risk of cataracts (adjusted OR 0.58; 95% CI, 0.40–0.85). Average tea consumption of 14–27 cups (adjusted OR 0.55; 95% CI, 0.33–0.93) and over 28 cups (adjusted OR 0.58; 95% CI, 0.34–0.99) per week had a protective effect against cataracts in comparison to no consumption. In addition, ingesting a moderate concentration of tea significantly decreased the risk of cataract compared to no consumption (adjusted OR 0.43; 95% CI, 0.27–0.71).ConclusionsTea ingestion was associated with reduced risk of age-related cataracts. In light of these findings, we suggest that reasonable tea consumption (ie, favoring green tea and consuming an average of over 500 mL per day at moderate concentration) should offer protection against age-related cataracts.

Associations of Polymorphisms in MTHFR Gene with the Risk of Age-Related Cataract in Chinese Han Population: A Genotype-Phenotype Analysis.

Homocysteine (Hcy) is a potential risk factor for age-related cataract (ARC). Methylenetetrahydrofolate reductase (MTHFR) is the key enzyme for Hcy metabolism, and variants of MTHFR may affect MTHFR enzyme activity. This study mainly evaluated the associations between variants in MTHFR gene, plasma MTHFR enzyme activity, total Hcy (tHcy) levels and ARC risk in Chinese population. Four single nucleotide polymorphisms (SNPs) in MTHFR gene were genotyped using the high-resolution melting (HRM) method in 502 ARC patients (mean age, 70.2 [SD, 9.0], 46.0% male) and 890 healthy controls (mean age, 67.1 [SD, 11.1], 47.6% male). The plasma MTHFR activity, folic acid (FA), vitamins B12 and B6 levels were detected by enzyme-linked immunosorbent assays (ELISA). The plasma tHcy levels were measured by an automated enzymatic assay. After the Bonferroni correction, the minor allele T of SNP rs1801133 showed a significant association with an increased risk of overall ARC (OR = 1.26, P = 0.003). Consistent association was also found between SNP rs1801133 and cortical ARC risk (OR = 1.44, P = 0.003). Haplotype analyses revealed an adverse effect of the haplotype "C-A-T-C" (alleles in order of SNPs rs3737967, rs1801131, rs1801133 and rs9651118) on ARC risk (OR = 1.55, P = 0.003). Moreover, in a joint analysis of SNPs rs9651118 and rs1801133, subjects with two unfavorable genotypes had a 1.76-fold increased risk of ARC compared with the reference group, and a statistically significant dose-response trend (Ptrend = 0.001) was also observed. Further, in healthy controls and patients with cortical ARC, the allele T of SNP rs1801133 and the increasing number of unfavorable genotypes were significantly correlated with decreased MTHFR activity as well as increased tHcy levels. However, there was no significant association between FA, vitamins B12, B6 levels and MTHFR variants. Our data indicated that variants in MTHFR gene might individually and jointly influence susceptibility to ARC by affecting MTHFR enzyme activity and tHcy levels.

The relationship between NQO1 C609T and CAT C-262Tgenetic polymorphisms and the risk of age-related cataracts.

Cataract is multi-factorial eye disease identified by the disturbance of the transparent ocular lens. There is significant evidence suggesting oxidative damage as a major cause of initiation and progression of numerous diseases including cataracts. NAD(P)H:quinone oxidoreductase 1 (NQO1; OMIM: 125860) and catalase (CAT, OMIM: 115500) are antioxidant enzymes that prevent cells from oxidative stress. The aim of the present study was to investigate the association between NQO1 C609T (Pro189Ser, rs1800566) and CAT promoter C-262T (rs1001179) genetic polymorphisms and the susceptibility to cataracts. A case-control study including 190 cataracts cases and 190 healthy subjects was carried out. Genotype distributions of NQO1 and CAT polymorphisms were examined using polymerase chain reactions and a restriction fragment length polymorphism (PCR-RFLP) approach to investigate the possible role of these polymorphisms as risk factors in the development of cataracts. Variant CT heterozygous and TT genotypes of the NQO1 C609T polymorphism were found to be associated with an increased risk of cataracts (CT vs CC, OR=1.61, 95%CI: 1.02-2.52, P=0.038), (CT/TT vs CC, OR=1.56, 95%CI: 1.02-2.4, P=0.040). In addition, compared to indoor work places and the CC genotype of NQO1, outdoor work places and CT/TT genotypes of NQO1 were found to increase the risk of age-related cataracts (OR=2.75, 95%CI: 1.20-6.33, P=0.017). The analysis did not reveal, however, any statistically significant (P>0.05) difference between CAT C-262T polymorphism and the risk of cataracts.

The Association of Outdoor Activity and Age-Related Cataract in a Rural Population of Taizhou Eye Study: Phase 1 Report.

PurposeTo study the relationship between outdoor activity and risk of age-related cataract (ARC) in a rural population of Taizhou Eye Study (phrase 1 report).MethodA population-based, cross-sectional study of 2006 eligible rural adults (≥45 years old) from Taizhou Eye Study was conducted from Jul. to Sep. 2012. Participants underwent detailed ophthalmologic examinations including uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), intraocular pressure (IOP), slit lamp and fundus examinations as well as questionnaires about previous outdoor activity and sunlight protection methods. ARC was recorded by LOCSⅢ classification system. The prevalence of cortical, nuclear and posterior subcapsular cataract were assessed separately for the risk factors and its association with outdoor activity.ResultsOf all 2006 eligible participants, 883 (44.0%) adults were diagnosed with ARC. The prevalence rates of cortical, nuclear and posterior subcapsular cataract per person were 41.4%, 30.4% and 1.5%, respectively. Women had a higher tendency of nuclear and cortical cataract than men (OR = 1.559, 95% CI 1.204–2.019 and OR = 1.862, 95% CI 1.456–2.380, respectively). Adults with high myopia had a higher prevalence of nuclear cataract than adults without that (OR = 2.528, 95% CI 1.055–6.062). Multivariable logistic regression revealed that age was risk factor of nuclear (OR = 1.190, 95% CI 1.167–1.213) and cortical (OR = 1.203, 95% CI 1.181–1.226) cataract; eyes with fundus diseases was risk factor of posterior subcapsular cataract (OR = 6.529, 95% CI 2.512–16.970). Outdoor activity was an independent risk factor of cortical cataract (OR = 1.043, 95% CI 1.004–1.083). The risk of cortical cataract increased 4.3% (95% CI 0.4%-8.3%) when outdoor activity time increased every one hour. Furthermore, the risk of cortical cataract increased 1.1% (95% CI 0.1%-2.0%) when cumulative UV-B exposure time increased every one year.ConclusionOutdoor activity was an independent risk factor for cortical cataract, but was not risk factor for nuclear and posterior subcapsular cataract. The risk of cortical cataract increased 4.3% when outdoor activity time increased every one hour. In addition, the risk of cortical cataract increased 1.1% (95% CI 0.1%-2.0%) when cumulative UV-B exposure time increased every one year.

Association between serum 25-hydroxyvitamin D levels and age-related cataracts

To investigate associations between serum 25-hydroxyvitamin D levels and age-related cataracts. Department of Ophthalmology, College of Medicine, Catholic University of Korea, South Korea. Observational cross-sectional study. Participants aged 40 years or older in the fourth (2008 to 2009) and fifth (2010 to 2012) Korea National Health and Nutrition Examination Survey (KNHANES) had evaluation of their serum 25-hydroxyvitamin D levels and ophthalmic slitlamp examinations to identify cataract. An age-related cataract was defined as the presence of a cortical, nuclear, anterior subcapsular, posterior subcapsular, or mixed cataract or a history of cataract surgery. The study evaluated eyes of 18 804 patients. The mean levels of serum 25-hydroxyvitamin D were 20.0 ng/mL in men and 17.5 ng/mL in women. In men, but not in women, the odds ratio (OR) for age-related cataracts decreased statistically significantly when the serum 25-hydroxyvitamin D levels were in the highest quintile than when they were in the lowest quintile (OR, 0.76; 95% confidence interval, 0.59-0.99) after adjusting for potentially confounding factors including age, sex, smoking status, diabetes, hypertension, and sunlight exposure. However, trend analysis did not show a significant declining trend in the cataract risk associated with higher serum 25-hydroxyvitamin D quintiles (P = .084). In women, serum 25-hydroxyvitamin D levels were not associated with age-related cataracts. The age-related cataract risk decreased in men with higher serum 25-hydroxyvitamin D levels than in those with lower serum 25-hydroxyvitamin D levels after adjusting for potential confounding factors. In light of previous research indicating an antioxidative effect of vitamin D, the connection between vitamin D and age-related cataract warrants further study. Neither author has a financial or proprietary interest in any material or method mentioned.

Different amounts of alcohol consumption and cataract: a meta-analysis.

To evaluate the association between different amounts of alcohol consumption and the risk of age-related cataract. We searched PubMed and Embase from their inception until May 2014 for case-control or cohort studies with data on alcohol consumption and age-related cataract. Heavy alcohol consumption was defined as more than two standard drinks per day, which is equal to a daily intake of 20 g of alcohol or 140 g per week. Moderate consumption was defined as less than 20 g of alcohol per day but more than never any. We performed separate meta-analyses for the associations of moderate or heavy alcohol consumption with age-related cataract under a random-effects model, respectively. Five case-control and five cohort studies were identified through comprehensive literature search. In the meta-analysis of 10 studies, the associations between moderate alcohol consumption and age-related cataract were marginally nonsignificant (pooled relative risk, 0.88; 95% confidence interval, 0.74 to 1.05; I = 82.1%), whereas heavy alcohol consumption was associated with an increased risk of age-related cataract (pooled relative risk, 1.26; 95% confidence interval, 1.06 to 1.50; I = 58.9%). The association between heavy alcohol consumption and cataract was stronger in case-control than in cohort studies. Adjusting for smoking as a potential confounder attenuated the association between heavy alcohol consumption and cataract. Heavy alcohol consumption significantly increased the risk of age-related cataract, whereas moderate consumption may be protective for this ocular condition. Clinically, information on a patient's alcohol drinking history might be valuable to general physicians and ophthalmologists when there is a diagnosis of age-related cataract and should be collected on a routine basis in eye clinics.

Association of vitamin C with the risk of age-related cataract: a meta-analysis.

Whether vitamin C is a protective factor for age-related cataract remains unclear. Thus, we conducted a meta-analysis to summarize the evidence from epidemiological studies of vitamin C and the risk of age-related cataract. Pertinent studies were identified by searching in PubMed and in Webscience. The random effect model was used to combine the results. Meta-regression and subgroups analyses were used to explore potential sources of between-study heterogeneity. Publication bias was estimated using Egger's regression asymmetry test. Finally, 15 articles with 20 studies for vitamin C intake and eight articles with 10 studies for serum ascorbate were included in this meta-analysis. The relative risk (RR) and 95% confidence interval of cataract for the highest versus the lowest category of vitamin C intake was 0.814 (0.707-0.938), and the associations were significant in America and Asia. Significant association of cataract risk with highest versus the lowest category of serum ascorbate was found in general [0.704 (0.564-0.879)]. Inverse associations were also found between serum ascorbate and nuclear cataract and posterior subcapsular cataract. Higher vitamin C intake and serum ascorbate might be inversely associated with risk of cataract. Vitamin C intake should be advocated for the primary prevention of cataract.

Vitamin E and risk of age-related cataract: a meta-analysis.

We conducted a meta-analysis to evaluate the relationship between vitamin E and age-related cataract (ARC). The fixed- or random-effect model was selected based on heterogeneity. Meta-regression was used to explore potential sources of between-study heterogeneity. Publication bias was evaluated using Begg's test. The dose-response relationship was assessed by a restricted cubic spline model. Relevant studies were identified by a search of PubMed and the Cochrane Library to May 2014, without language restrictions. Studies involved samples of people of all ages. Dietary vitamin E intake, dietary and supplemental vitamin E intake, and high serum tocopherol levels were significantly associated with decreased risk of ARC, the pooled relative risk was 0·73 (95% CI 0·58, 0·92), 0·86 (95% CI 0·75, 0·99) and 0·77 (95% CI 0·66, 0·91), respectively. Supplemental vitamin E intake was non-significantly associated with ARC risk (relative risk=0·92; 95% CI 0·78, 1·07). The findings from dose-response analysis showed evidence of a non-linear association between dietary vitamin E intake and ARC. The risk of ARC decreased with dietary vitamin E intake from 7 mg/d (relative risk=0·94; 95% CI 0·90, 0·97). The findings of the meta-analysis indicated that dietary vitamin E intake, dietary and supplemental vitamin E intake, and high level of serum tocopherol might be significantly associated with reduced ARC risk.

Flavonoid intake and the risk of age-related cataract in China's Heilongjiang Province

Background/objectivesEpidemiological evidence suggests that diets rich in flavonoids may reduce the risk of developing age-related cataract (ARC). Flavonoids are widely distributed in foods of plant origin, and the objective of this study was to evaluate retrospectively the association between the intakes of the five flavonoid subclasses and the risk of ARC.Subjects/methodsA population-based case-control study (249 cases and 66 controls) was carried out in Heilongjiang province, which is located in the northeast of China, and where intakes and availability of fresh vegetables and fruits can be limited. Dietary data gathered by food-frequency questionnaire (FFQ) were used to calculate flavonoid intake. Adjusted odds ratio (OR) and 95% confidence interval (CI) were estimated by logistic regression.ResultsNo linear associations between risk of developing ARC and intakes of total dietary flavonoids, anthocyanidins, flavon-3-ol, flavanone, total flavones or total flavonols were found, but quercetin and isorhamnetin intake was inversely associated with ARC risk (OR 11.78, 95% CI: 1.62–85.84, p<0.05, and OR 6.99, 95% CI: 1.12–43.44, p<0.05, quartile 4 vs. quartile 1, respectively).ConclusionAs quercetin is contained in many plant foods and isorhamnetin in very few foods, we concluded that higher quercetin intake may be an important dietary factor in the reduction of the risk of ARC.

Iris color and associated pathological ocular complications: a review of epidemiologic studies.

To elucidate the associations of iris color with major eye diseases. A systematic search on Medline with coverage up to August 2013 was conducted. Assessment of the quality of studies based on their levels of evidence was in accordance with the Centre for Evidence-Based Medicine, Oxford, United Kingdom. A relationship between darker iris color and an increased risk of age-related cataract has been reported from cross-sectional studies and prospective cohort studies. There was no consistent evidence supporting a major role of iris color in the development or progression of age-related macular degeneration. The association of iris color with ocular uveal melanoma has been confirmed by a meta-analysis of observational studies previously. The etiologic synergism between light iris color and environmental exposure such as UV the exposure of UV radiation was found. There were no studies evaluating the refractive associations with iris color but there may be a possible link between iris color and myopia. Darker iris color is associated with an increased risk of cataract and a reduced risk of ocular uveal melanoma. The association of iris color with age-related macular degeneration is not confirmed. Ophthalmologists should be aware that the risk of ocular disorders appears to vary by differences in iris color.

Polymorphisms of DNA Repair Genes XPD (Lys751Gln) and XRCC1 (Arg399Gln), and The Risk of Age-Related Cataract: A Meta-Analysis

Purpose: A meta-analysis of available studies was used to test the association between two DNA repair genes and age-related cataract.Materials and Methods: A systematic search of the Chinese National Knowledge Infrastructure, EMBASE and PubMed databases identified six studies that were analyzed. Meta-analysis was used to evaluate single nucleotide polymorphisms (SNP) of the DNA repair gene xeroderma pigmentosum complementation group D (XPD) (Lys751Gln) and the X-ray repair cross-complementing gene 1 (XRCC1) (Arg399Gln). Only articles published before June 6, 2014, were included. The quality of the studies was determined using Newcastle–Ottawa Scale tools. The summary odds ratio (OR) and corresponding confidence interval (CI) for XPD Lys751Gln and XRCC1 Arg399Gln polymorphisms and risk of age-related cataract were estimated by random and fixed-effects models. Sensitivity analysis was employed to determine the robustness of the conclusions.Results: Six studies, with a total of 1518 patients with cataractous lenses and 1437 subjects with clear lenses, were included in the meta-analysis. XRCC1 Arg399Gln polymorphisms were associated with cataract risk (recessive model: ORfixed = 0.79, 95% CI: 0.67–0.93; dominant model: ORfixed = 0.84, 95% CI: 0.64–1.11; additive model: ORfixed = 0.82, 95% CI: 0.72–0.92). Analysis of Chinese, but not non-Chinese subgroups, confirmed this association. The OR of XPD Lys751Gln polymorphisms for cataract was not significant. The associations remained significant after sensitivity analysis.Conclusions: This meta-analysis indicates that XRCC1 Arg399Gln polymorphisms, but not XPD Lys751Gln polymorphisms, are associated with risk of age-related cataract.

Ameliorative effects of SkQ1 eye drops on cataractogenesis in senescence-accelerated OXYS rats.

Antioxidant supplements have been suggested as a strategy to decrease the risk of age-related cataract, but there is no evidence that antioxidants can reduce the signs of the disease. Recently, we showed that the mitochondrial antioxidant SkQ1 can partially reverse cataract signs in senescence-accelerated OXYS rats. The aim of the present study was the histomorphological examination of the influence of SkQ1 eye drops on the cataract development in OXYS rats. OXYS rats received SkQ1 eye drops (250 nM) from 9 to 12months of age. Ophthalmoscopic examination was carried out before and after treatment. Light and electron microscopy were used for histomorphological examination. Expression of the Cryaa and Cryab genes was determined using real-time PCR. αB-crystallin expression was detected using Western blotting. SkQ1 completely prevented the cataract development in OXYS rats, and in some of the animals diminished the signs of the disease. Light and electron microscopy showed that SkQ1 attenuated the (typical for cataract) alterations in the lens capsule and epithelial cells, ameliorated disturbances of the hexagonal packing geometry of lens fibers, and improved ultrastructure of the epithelial cells. The levels of mRNA of α-crystallins genes which encode small heat shock proteins αA- and αB-crystallin that play a central role in maintaining lens transparency were significantly lower in the OXYS rats' lenses than in Wistar rats (control). SkQ1 normalized the level of mRNA of Cryaa, and significantly increased the level of Cryab mRNA as well as αB-crystallin protein in the lens of OXYS rats to the level of the control Wistar rats. SkQ1 eye drops hold promise as a treatment of cataract.

Long-Term Physical Activity and Risk of Age-Related Cataract: A Population-Based Prospective Study of Male and Female Cohorts

To examine the association of total and specific types of physical activity, including walking or bicycling, exercising, work or occupational activity, home or housework, and leisure time inactivity with the risk of age-related cataract in women and men. Population-based prospective cohort study. A total of 52 660 participants (23 853 women and 28 807 men) 45 to 83 years of age from the Swedish Mammography Cohort and the Cohort of Swedish Men. Physical activity was assessed using a self-administered questionnaire at baseline. Cataract diagnosis and extraction were identified through linkage to registers. Incident age-related cataract diagnosis and cataract extraction. During a mean 12.1 years of follow-up (between January 1, 1998, and December 31, 2011; 634 631 person-years), 11 580 incident age-related cataract cases were identified. After adjusting for potential confounders, the highest quartile of total physical activity was statistically significantly associated with 13% decreased risk of cataract compared with the lowest (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.82-0.92). Walking or bicycling (>60 minutes/day vs. hardly ever; HR, 0.88; 95% CI, 0.82-0.95) and work or occupational activity (heavy manual labor vs. mostly sitting; HR, 0.84; 95% CI, 0.78-0.91) also were associated with decreased risk of cataract. Exercise training and home or housework were not associated with cataract risk. Leisure time inactivity was associated with increased risk of cataract (>6 vs. <1 hours/day; HR, 1.27; 95% CI, 1.07-1.50). The HR for high long-term total physical activity compared with low levels both at 30 years of age and at baseline was 0.76 (95% CI, 0.69-0.85). Our findings indicate that high total physical activity, especially in the long term, and such specific types of physical activity as walking or bicycling and work or occupational activity, may be associated with decreased risk of age-related cataract. Conversely, high inactivity levels may be associated with increased risk of cataract.

Alcohol intake and the risk of age-related cataracts: a meta-analysis of prospective cohort studies.

PurposeEpidemiologic studies assessing the relationship between alcohol consumption and the risk of age-related cataracts (ARCs) led to inconsistent results. This meta-analysis was performed to fill this gap.MethodsEligible studies were identified via computer searches and reviewing the reference lists of these obtained articles. Pooled estimates of the relative risks (RR) and the corresponding 95% confidence Intervals (CI) were calculated using random effects models.ResultsSeven prospective cohort studies involving a total of 119,706 participants were ultimately included in this meta-analysis. Pooled results showed that there is no substantial overall increased risk of ARC due to heavy alcohol consumption. The estimated RRs comparing heavy drinkers versus non-drinkers were 1.25 (95% CI: 1.00, 1.56) for cataract sugery, 1.06 (95% CI: 0.63, 1.81) for cortical cataracts, 1.26 (95% CI: 0.93, 1.73) for nuclear cataracts, and 0.91 (95% CI: 0.32, 2.61) for posterior subcapsular cataracts (PSCs), respectively. No significant associations between moderate alcohol consumption and cataracts were observed. The pooled RRs comparing moderate drinkers versus non-drinkers were 0.90 (95% CI: 0.64, 1.26) for cataract surgery, 0.97 (95% CI: 0.75, 1.25) for cortical cataracts, 0.91 (95% CI: 0.76, 1.08) for nuclear cataracts, and 0.97 (95% CI: 0.49, 1.91) for PSCs, respectively.ConclusionsThis meta-analysis suggests that there is no substantial overall increased risk of ARC due to alcohol intake. Because of the limited number of studies, the findings from our study must be confirmed in future research via well-designed cohort or intervention studies.

Association between dietary carbohydrate intake and dietary glycemic index and risk of age-related cataract: a meta-analysis.

To assess the association of dietary carbohydrate intake and dietary glycemic index (GI), and risk of age-related cataract (ARC), and quantitatively estimate their dose-response relationships. We searched Medline, the Cochrane Library, Excerpta Medica database (EMBASE), Institute for Scientific Information (ISI) Science Citation Index, ISI Web of Knowledge, and China National Knowledge Infrastructure (CNKI) databases before October 2013. Two authors independently extracted data and assessed study quality. The random-effect model was used to calculate the pooled odds ratios (ORs). Dose-response analyses, subgroup analyses based on ARC subtypes, heterogeneity, and publication bias assessment were also carried out. Seven studies were included in our meta-analysis. The pooled ORs of ARC for the highest versus the lowest category of carbohydrate intake and GI were 1.18 (95% confidence interval [CI]: 1.01-1.38) and 1.15 (95% CI: 1.00-1.32), respectively. Further subgroup analyses based on ARC subtypes suggested a marginally significant association between higher carbohydrate intake and cortical cataract risk (OR: 1.37, 95% CI: 0.99-1.90), and a statistically significant association between higher GI and nuclear cataract risk (OR: 1.23, 95% CI: 1.03-1.46). In addition, a significant dose-response relationship was observed between carbohydrate intake and the risk of cortical cataract. Our results indicate that higher dietary carbohydrate quantity and GI may be associated with the risk of cortical and nuclear cataract, respectively. The results should be interpreted cautiously and more studies are warranted to clarify this issue.

Overweight, Obesity, and Age-Related Cataract

To examine the longitudinal association of overweight/obesity with age-related cataract. A systematic review of the literature was performed using PubMed and Embase from their inception until June 2013 for prospective data on body mass index categories identical or similar to the World Health Organization-recommended classifications of body weight and age-related cataract including nuclear, cortical, and posterior subcapsular (PSC) cataract. Meta-analyses were conducted using random-effects models with results reported as adjusted relative risks (RRs). A total of 163,013 subjects aged 40 to 84 years from six prospective cohort studies were included in the meta-analysis. Obesity was associated with an increasing risk of nuclear cataract (pooled RR, 1.12; 95% confidence interval [CI], 1.02 to 1.25), cortical cataract (pooled RR, 1.34; 95% CI, 1.07 to 1.66), and PSC cataract (pooled RR, 1.52; 95% CI, 1.31 to 1.77). Overweight was only associated with an increasing risk of PSC cataract (pooled RR, 1.23; 95% CI, 1.09 to 1.40). The longitudinal associations of obesity with incident age-related cataract are confirmed by the findings in this six-study meta-analysis. The association of obesity with PSC cataract is stronger than that with nuclear or cortical cataract. Randomized control trials are warranted to examine the effectiveness and cost-effectiveness of weight reduction in obese populations to decrease the risk of age-related cataract.

Are Increased Levels of Systemic Oxidative Stress and Inflammation Associated with Age-Related Cataract?

Oxidative stress and inflammation may be involved in the etiology of age-related cataract. This study is the first to investigate the association between urinary levels of 8-iso-prostaglandin F₂α (PGF₂α; as a biomarker for systemic oxidative stress in vivo) and 15-keto-dihydro-PGF₂α (as a biomarker for systemic inflammation in vivo) and risk of age-related cataract. We observed in a nested case-control study, including 258 women with incident cataract diagnosis and/or cataract extraction and 258 women without cataract, matched on age and date of urine sample collection that, women with higher levels of urinary 8-iso-PGF₂α as compared with lower levels had an increased risk of age-related cataract. There was no difference in 15-keto-dihydro-PGF₂α levels between cases and controls. Our observations lead to the hypothesis that higher systemic oxidative stress increases the risk of developing age-related cataract.