Cigarette smoking and the natural history of age-related macular degeneration: the Beaver Dam Eye Study

Aqueous humor perturbations in chronic smokers: a proteomic study

The detrimental effects of smoking are multisystemic and its effects on the eye health are significant. Smoking is a strong risk factor for age-related nuclear cataract, age-related macular degeneration, glaucoma, delayed corneal epithelial healing and increased risk of cystoid macular edema in patients with intermediate uveitis among others. We aimed to characterize the aqueous humor (AH) proteome in chronic smokers to gain insight into its perturbations and to identify potential biomarkers for smoking-associated ocular pathologies. Compared to the control group, chronic smokers displayed 67 (37 upregulated, 30 downregulated) differentially expressed proteins (DEPs). Analysis of DEPs from the biological point of view revealed that they were proteins involved in complement activation, lymphocyte mediated immunity, innate immune response, cellular oxidant detoxification, bicarbonate transport and platelet degranulation. From the molecular function point of view, DEPs were involved in oxygen binding, oxygen carrier activity, hemoglobin binding, peptidase/endopeptidase/cysteine-type endopeptidase inhibitory activity. Several of the upregulated proteins were acute phase reactant proteins such as clusterin, alpha-2-HS-glycoprotein, fibrinogen, alpha-1-antitrypsin, C4b-binding protein and serum amyloid A-2. Further research should confirm if these proteins might serve as biomarkers or therapeutic target for smoking-associated ocular diseases.

Smoking and short-term response to intravitreal anti-Vascular Endothelial Growth Factor injections in neovascular age-related macular degeneration

PURPOSE

To evaluate the role of smoking status on the response to three monthly intravitreal anti-Vascular Endothelial Growth Factor (anti-VEGF) injections in treatment-naive neovascular AMD (nAMD) patients.

METHODS

We conducted a single-center, retrospective, case-control cohort study in Belgium.

RESULTS

Intravitreal treatment (IVT) was performed in 147 eyes of 131 patients, including 92 females (70%). Mean age at the time of the first IVT was 79±9 years. Seventeen patients (13%) were actively smoking at the time of the anti-VEGF IVT. On average, active smokers were 11 years younger than non-smokers when starting IVT treatment. They also showed more frequent subretinal fluid than non-smokers (94% vs. 65%). Mann-Whitney analyses comparing change in central macular thickness and change in logarithm of the minimum angle of resolution visual acuity between active smokers and non-smokers showed no significant difference in treatment response between both groups. Likewise, no significant difference was found when comparing treatment response between patients with less than 10 pack-years (PY) (including never-smokers) and patients with over 10 PY. In a binary logistic regression model, male patients responded worse to anti-VEGF IVT than their female counterparts, with an odds ratio (OR) of 0.27 for good response. This was the only statistically significant predictor of treatment response.

CONCLUSION

Our study failed to demonstrate an effect of smoking on the short-term treatment response to anti-VEGF in nAMD.

Acute and continuous exposure of airborne fine particulate matter (PM2.5): diverse outer blood-retinal barrier damages and disease susceptibilities

BACKGROUND

The association between air pollution and retinal diseases such as age-related macular degeneration (AMD) has been demonstrated, but the pathogenic correlation is unknown. Damage to the outer blood-retinal barrier (oBRB), which consists of the retinal pigment epithelium (RPE) and choriocapillaris, is crucial in the development of fundus diseases.

OBJECTIVES

To describe the effects of airborne fine particulate matter (PM2.5) on the oBRB and disease susceptibilities.

METHODS

A PM2.5-exposed mice model was established through the administration of eye drops containing PM2.5. Optical coherence tomography angiography, transmission electron microscope, RPE immunofluorescence staining and Western blotting were applied to study the oBRB changes. A co-culture model of ARPE-19 cells with stretching vascular endothelial cells was established to identify the role of choroidal vasodilatation in PM2.5-associated RPE damage.

RESULTS

Acute exposure to PM2.5 resulted in choroidal vasodilatation, RPE tight junctions impairment, and ultimately an increased risk of retinal edema in mice. These manifestations are very similar to the pachychoroid disease represented by central serous chorioretinopathy (CSC). After continuous PM2.5 exposure, the damage to the RPE was gradually repaired, but AMD-related early retinal degenerative changes appeared under continuous choroidal inflammation.

CONCLUSION

This study reveals oBRB pathological changes under different exposure durations, providing a valuable reference for the prevention of PM2.5-related fundus diseases and public health policy formulation.

Effect of statins on the age of onset of age-related macular degeneration

BACKGROUND

This study evaluated the relationship between statin use and the age of onset of age-related macular degeneration (AMD).

METHODS

Electronic Health Records from 52,840 patients evaluated at University of California Los Angeles (UCLA) Ophthalmology Clinics and 9,977 patients evaluated at University of California San Francisco (UCSF) Ophthalmology Clinics were screened. Survival analysis was performed using Cox proportional hazards regression models and visualized using Kaplan Meier survival curves, with the following covariates-sex, ethnicity, smoking history, fluoxetine use, obesity, diabetes mellitus, and hypertension.

RESULTS

5,498 of 52,840 patients at UCLA were diagnosed with AMD. Statin use was associated with a later AMD onset (HR = 0.8823, p < 0.0001), while female sex (HR = 1.0852, p= 00,035), obesity (HR = 1.4555, p < 0.0001), and fluoxetine (HR = 1.3797, p= 0.0003) were associated with an earlier AMD onset. Non-hispanic black (HR = 0.5687, p < 0.0001) and hispanic ethnicities (HR = 0.8269, p= 0.0028) were associated with a later AMD onset. When stratifying for ethnicity, statins, fluoxetine, sex, and obesity were significant only within non-hispanic white subjects. Statin use was significant among patients with dry AMD (HR = 0.8410, p= 0.0001) but not wet AMD (0.9188, p= 0.0351). In the replication cohort, 526 of 9,977 patients at UCSF had AMD. Associations between statins (HR = 0.7643, p= 0.0033), non-hispanic black ethnicity (HR = 0.5043, p= 0.0035), and obesity (HR = 1.9602, p < 0.0001) on AMD onset were confirmed.

CONCLUSIONS

In both cohorts, statin use and non-hispanic black ethnicity are associated with a later AMD onset, while obesity with an earlier AMD onset.

Antioxidative Role of Heterophagy, Autophagy, and Mitophagy in the Retina and Their Association with the Age-Related Macular Degeneration (AMD) Etiopathogenesis

Age-related macular degeneration (AMD), an oxidative stress-linked neurodegenerative disease, leads to irreversible damage of the central retina and severe visual impairment. Advanced age and the long-standing influence of oxidative stress and oxidative cellular damage play crucial roles in AMD etiopathogenesis. Many authors emphasize the role of heterophagy, autophagy, and mitophagy in maintaining homeostasis in the retina. Relevantly modifying the activity of both macroautophagy and mitophagy pathways represents one of the new therapeutic strategies in AMD. Our review provides an overview of the antioxidative roles of heterophagy, autophagy, and mitophagy and presents associations between dysregulations of these molecular mechanisms and AMD etiopathogenesis. The authors performed an extensive analysis of the literature, employing PubMed and Google Scholar, complying with the 2013-2023 period, and using the following keywords: age-related macular degeneration, RPE cells, reactive oxygen species, oxidative stress, heterophagy, autophagy, and mitophagy. Heterophagy, autophagy, and mitophagy play antioxidative roles in the retina; however, they become sluggish and dysregulated with age and contribute to AMD development and progression. In the retina, antioxidative roles also play in RPE cells, NFE2L2 and PGC-1α proteins, NFE2L2/PGC-1α/ARE signaling cascade, Nrf2 factor, p62/SQSTM1/Keap1-Nrf2/ARE pathway, circulating miRNAs, and Yttrium oxide nanoparticles performed experimentally in animal studies.

The value of pre-symptomatic genetic risk assessment for age-related macular degeneration: the Moran AMD Genetic Testing Assessment (MAGENTA) study-a study protocol for a randomized controlled trial

BACKGROUND

Age-related macular degeneration (AMD) is an irreversible blinding eye condition with complex genetic and environmental etiologies. Genetic testing for AMD for previously identified multiple-risk single nucleotide polymorphisms can help determine an individual's future susceptibility. However, such testing has been discouraged until evidence shows that providing such information to symptomatic or pre-symptomatic individuals will alter their disease course. Therefore, we designed this study to investigate whether knowledge of AMD risk could stimulate the adoption of a healthier lifestyle that could lower the incidence of AMD later in life. We hypothesize that pre-symptomatic individuals informed of a high genetic risk of AMD are more likely to make quantifiable, positive lifestyle changes relative to participants informed of lower genetic risk or randomized to deferred disclosure of genetic testing results.

METHODS

The Moran AMD Genetic Testing Assessment (MAGENTA) study is a phase 2, single-center, prospective, double-masked, randomized controlled trial conducted at the John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Participants are randomized by a 3:1 allocation ratio to immediate and deferred disclosure groups and followed for 12 months. Skin, ocular, and serum carotenoid status, as well as nutritional and social surveys, are assessed at study visits. Skin carotenoid assessment is by resonance Raman spectroscopy and reflectance spectroscopy, ocular carotenoids are measured with Heidelberg Spectralis autofluorescence imaging and fluorescence lifetime imaging ophthalmoscopy (FLIO), and serum carotenoids are quantified using high-performance liquid chromatography. The primary outcome evaluates changes in skin carotenoid status in response to genetic risk disclosure. The secondary outcomes examine changes in ocular and serum carotenoid status in response to genetic risk disclosure. Also, we will correlate AMD genetic risk with baseline ocular and systemic carotenoid status and FLIO.

DISCUSSION

MAGENTA will provide much-needed evidence on whether pre-symptomatic testing for AMD risk can lead to quantifiable long-term changes in behavior and lifestyle associated with a lower incidence of AMD later in life. Findings from the MAGENTA trial will facilitate the design of a future larger, longer-term, multicenter phase 3 trial that could feature subgroup analysis, expanded measures of lifestyle modification, and potential active nutritional interventions.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05265624 . Registered on March 3, 2022.

Rethinking the potential and necessity of drug delivery systems in neovascular age-related macular degeneration therapy

Age-related macular degeneration (AMD) is the predominant threat to human vision and ultimately results in blindness. With the increase in the aging population, it has become a more crucial issue to human health. AMD is a multifactorial disease with the unique feature of uncontrollable angiogenesis during initiation and progression. Although increasing evidence indicates that AMD is largely hereditary, the predominant efficient treatment is antiangiogenesis, which mainly involves VEGF and HIF-α as therapeutic targets. The repeated administration of this treatment over the long term, generally through intravitreal injection, has called for the introduction of long-term drug delivery systems, which are expected to be achieved by biomaterials. However, the clinical results of the port delivery system indicate that the optimization of medical devices toward prolonging the activities of therapeutic biologics in AMD therapy seems more promising. These results indicate that we should rethink the possibility and potential of biomaterials as drug delivery systems in achieving long-term, sustained inhibition of angiogenesis in AMD therapy. In this review, the etiology, categorization, risk factors, pathogenesis, and current clinical treatments of AMD are briefly introduced. Next, the development status of long-term drug delivery systems is discussed, and the drawbacks and shortages of these systems are emphasized. By comprehensively considering the pathological aspect and the recent application of drug delivery systems in AMD therapy, we hope to find a better solution for the further development of long-term therapeutic strategies for AMD.

Association of cigarette smoking with retinal capillary plexus: an optical coherence tomography angiography study

PURPOSE

To investigate the association between cigarette smoking and retinal capillary plexus (RCP) using optical coherence tomography angiography (OCTA) and to examine whether potential vascular risk factors could impact their association.

METHODS

This is a cross-sectional, community-based study. The Jidong Eye Cohort Study included participants aged ≥18 years in the Jidong community (Tangshan city, northern China) from August 2019 to January 2020. All participants underwent comprehensive ophthalmic examination and completed detailed smoking questionnaires. Retinal vessel density in the superficial and deep RCP was automatically measured using OCTA.

RESULTS

Of the 2598 participants included in the study, 2026 (78.0%) never smoked and 572 (22.0%) had a history of smoking (494 [19.0%] current smokers and 78 [3.0%] former smokers). The median (interquartile range) age was 41 (34-52) years for the non-smoking group and 45 (35-54.5) years for the smoking group. Multivariable analysis showed that smoking history is associated with a low deep RCP vessel density in the parafovea (β, -0.53; 95% confidence interval [CI], -0.82 to -0.24) and four quadrants. Increased smoking pack-years were associated with reduced deep RCP vessel density in the parafovea (p for trend <0.001) and four quadrants. The significant interaction between diabetes and smoking only was found for superficial RCP vessel density in the parafovea (p for interaction = 0.014) and four quadrants except for the temporal quadrants.

CONCLUSIONS

Cigarette smoking is an independent risk factor for reduced deep RCP vessel density. Our findings imply the potential detrimental effect of smoking on the occurrence of ocular diseases.

The role of retinal fluid location in atrophy and fibrosis evolution of patients with neovascular age-related macular degeneration long-term treated in real world

PURPOSE

To assess the effect of clinical factors on the development and progression of atrophy and fibrosis in patients with neovascular age-related macular degeneration (nAMD) receiving long-term treatment in the real world.

METHODS

An ambispective 36-month multicentre study, involving 359 nAMD patients from 17 Spanish hospitals treated according to the Spanish Vitreoretinal Society guidelines, was designed. The influence of demographic and clinical factors, including the presence and location of retinal fluid, on best-corrected visual acuity (BCVA) and progression to atrophy and/or fibrosis were analysed.

RESULTS

After 36 months of follow-up and an average of 13.8 anti-VEGF intravitreal injections, the average BCVA gain was +1.5 letters, and atrophy and/or fibrosis were present in 54.8% of nAMD patients (OR = 8.54, 95% CI = 5.85-12.47, compared to baseline). Atrophy was associated with basal intraretinal fluid (IRF) (OR = 1.87, 95% CI = 1.09-3.20), whereas basal subretinal fluid (SRF) was associated with a lower rate of atrophy (OR = 0.40, 95% CI = 0.23-0.71) and its progression (OR = 0.44, 95% CI = 0.26-0.75), leading to a slow progression rate (OR = 0.34, 95% CI = 0.14-0.83). Fibrosis development and progression were related to IRF at any visit (p < 0.001). In contrast, 36-month SRF was related to a lower rate of fibrosis (OR = 0.49, 95% CI = 0.29-0.81) and its progression (OR = 0.50, 95% CI = 0.31-0.81).

CONCLUSION

Atrophy and/or fibrosis were present in 1 of 2 nAMD patients treated for 3 years. Both, especially fibrosis, lead to vision loss. Subretinal fluid (SRF) was associated with good visual outcomes and lower rates of atrophy and fibrosis, whereas IRF yields worse visual results and a higher risk of atrophy and especially fibrosis in routine clinical practice.

Genotyping of Clinical Parameters in Age-Related Macular Degeneration

Background

Methods

Results

Conclusion

Global, regional, and national burden of blindness and vision loss due to common eye diseases along with its attributable risk factors from 1990 to 2019: a systematic analysis from the global burden of disease study 2019

To map the magnitudes and temporal trends of blindness and vision loss (BVL) due to common eye diseases along with its attributable risk factors at the national, regional, and global levels. The annual burden of BVL in 204 countries and territories was extracted from the Global Burden of Disease Study 2019. The estimated annual percentage change (EAPC) and causes composition change were calculated to quantify the temporal trends of BVL-related disease burden by sex, region, and eye disease. The global disability-adjusted life years (DALYs) of BVL increased from 12.44 million in 1990 to 22.56 million in 2019, with a slightly decreased rate from 3.03 to 2.78 per 1000 population (EAPC = -0.30). About 29.6% of BVL-related DALYs worldwide were caused by cataract, followed by refraction disorders (29.1%), near vision loss (21.7%), other vision loss (13.7%), glaucoma (3.3%), and age-related macular degeneration (2.5%) in 2019. The age-standardized DALYs rates due to each eye disease type in most regions were decreased, especially in countries with high burden and high-middle socio-demographic index. Moreover, the contribution of smoking and air pollution from solid fuels to BVL burden decreased, however, the age-standardized burden of BVL attributed to high body-mass index and high fasting plasma glucose elevated gradually across almost all regions. The temporal trend of BVL burden due to specific eye diseases varies remarkably by region, sex and age. Understanding the real-time patterns of BVL burden is crucial for formulating more effective and targeted prevention and healthcare strategies to decrease the BVL burden.

Prevention of the Onset of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) represents the leading cause of irreversible blindness in elderly people, mostly after the age of 65. The progressive deterioration of visual function in patients affected by AMD has a significant impact on quality of life and has also high social costs. The current therapeutic options are only partially able to slow down the natural course of the disease, without being capable of stopping its progression. Therefore, better understanding of the possibilities to prevent the onset of the disease is needed. In this regard, a central role is played by the identification of risk factors, which might participate to the development of the disease. Among these, the most researched are dietary risk factors, lifestyle, and light exposure. Many studies showed that a higher dietary intake of nutrients, such as lutein, zeaxanthin, beta carotene, omega-3 fatty acids and zinc, reduced the risk of early AMD. Regarding lifestyle habits, the association between smoking and AMD is currently accepted. Finally, retinal damage caused by ultraviolet rays and blue light is also worthy of attention. The scope of this review is to summarize the present knowledge focusing on the measures to adopt in order to prevent the onset of AMD.

Age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of legal blindness in the industrialized world. AMD is characterized by accumulation of extracellular deposits, namely drusen, along with progressive degeneration of photoreceptors and adjacent tissues. AMD is a multifactorial disease encompassing a complex interplay between ageing, environmental risk factors and genetic susceptibility. Chronic inflammation, lipid deposition, oxidative stress and impaired extracellular matrix maintenance are strongly implicated in AMD pathogenesis. However, the exact interactions of pathophysiological events that culminate in drusen formation and the associated degeneration processes remain to be elucidated. Despite tremendous advances in clinical care and in unravelling pathophysiological mechanisms, the unmet medical need related to AMD remains substantial. Although there have been major breakthroughs in the treatment of exudative AMD, no efficacious treatment is yet available to prevent progressive irreversible photoreceptor degeneration, which leads to central vision loss. Compelling progress in high-resolution retinal imaging has enabled refined phenotyping of AMD in vivo. These insights, in combination with clinicopathological and genetic correlations, have underscored the heterogeneity of AMD. Hence, our current understanding promotes the view that AMD represents a disease spectrum comprising distinct phenotypes with different mechanisms of pathogenesis. Hence, tailoring therapeutics to specific phenotypes and stages may, in the future, be the key to preventing irreversible vision loss.

Ten-Year Progression From Intermediate to Exudative Age-Related Macular Degeneration and Risk Factors: Bundang AMD Cohort Study Report 1

PURPOSE

This study investigated the 10-year incidence of progression from intermediate to exudative age-related macular degeneration (AMD) and identified genetic and environmental factors influencing that progression in the Korean population.

DESIGN

Retrospective, observational cohort study.

METHODS

In total, 632 eyes of 418 patients (age: ≥50 years) with intermediate AMD were enrolled. The incidence of exudative AMD was assessed from color fundus photographs and optical coherence tomography images obtained at baseline and during annual visits. Data regarding lifestyle variables and dietary habits were acquired through comprehensive questionnaires. Genotyping data concerning 3 single nucleotide polymorphisms (SNPs), rs800292 and rs1061170 in the CFH gene and rs10490924 in ARMS2 were also analyzed. The cumulative incidence of exudative changes was estimated using Kaplan-Meier analysis. Associated influential factors were evaluated using univariate and multivariate Cox regression models.

RESULTS

The mean follow-up period was 3.99 ± 2.85 years. The cumulative incidence of progression to exudative AMD was 5.6%, 14.8%, and 28.4% at 2, 5, and 10 years, respectively. Multivariate Cox analysis showed that age (hazard ratio [HR]: 1.041; P = .0393), family history of AMD (HR: 3.175; P = .0184), and pre-existing exudative AMD in the fellow eye (HR: 3.186; P = 5.31 × 10^-5) were positively associated with exudative changes. Regular intake of green tea (HR: 0.632; P = .0475) was associated with a decrease in exudative changes. The ARMS2 SNP rs10490924 (HR: 1.482; P = .0185) showed a significant association with AMD progression.

CONCLUSIONS

The annual progression rate from intermediate to exudative AMD in the Korean population is approximately 2.8%, which is comparable with that for whites. Intake of green tea may be a modifiable protective factor against exudative changes.

Age-Related Macular Degeneration: Epidemiology and Clinical Aspects

Age-related macular degeneration (AMD) is a degenerative disease of the human retina affecting individuals over the age of 55 years. This heterogeneous condition arises from a complex interplay between age, genetics, and environmental factors including smoking and diet. It is the leading cause of blindness in industrialized countries. Worldwide, the number of people with AMD is predicted to increase from 196 million in 2020 to 288 million by 2040. By this time, Asia is predicted to have the largest number of people with the disease. Distinct patterns of AMD prevalence and phenotype are seen between geographical areas that are not explained fully by disparities in population structures. AMD is classified into early, intermediate, and late stages. The early and intermediate stages, when visual symptoms are typically absent or mild, are characterized by macular deposits (drusen) and pigmentary abnormalities. Through risk prediction calculators, grading these features helps predict the risk of progression to late AMD. Late AMD is divided into neovascular and atrophic forms, though these can coexist. The defining lesions are macular neovascularization and geographic atrophy, respectively. At this stage, visual symptoms are often severe and irreversible, and can comprise profoundly decreased central vision in both eyes. For these reasons, the condition has major implications for individuals and society, as affected individuals may experience substantially decreased quality of life and independence. Recent advances in retinal imaging have led to the recognition of an expanded set of AMD phenotypes, including reticular pseudodrusen, nonexudative macular neovascularization, and subtypes of atrophy. These developments may lead to refinements in current classification systems.

Use of Composite End Points in Early and Intermediate Age-Related Macular Degeneration Clinical Trials: State-of-the-Art and Future Directions

The slow progression of early age-related macular degeneration (AMD) stages to advanced AMD requires the use of surrogate end points in clinical trials. The use of combined end points may allow for shorter and smaller trials due to increased precision. We performed a literature search for the use of composite end points as primary outcome measures in clinical studies of early AMD stages. PubMed was searched for composite end points used in early/intermediate AMD studies published during the last 10 years. A total of 673 articles of interest were identified. After reviewing abstracts and applicable full-text articles, 33 articles were eligible and thus included in the qualitative synthesis. The main composite end point categories were: combined structural and functional end points, combined structural end points, combined functional end points and combined multicategorical end points. The majority of the studies included binary composite end points. There was a lack of sensitivity analyses of different end points against accepted outcomes (i.e., progression) in the literature. Various composite outcome measures have been used but there is a lack of standardization. To date no agreement on the optimal approach to implement combined end points in clinical studies of early stages of AMD exists, and no surrogate end points have been accepted for AMD progression.

Genetic Risk, Lifestyle, and Age-Related Macular Degeneration in Europe: The EYE-RISK Consortium

PURPOSE

Age-related macular degeneration (AMD) is a common multifactorial disease in the elderly with a prominent genetic basis. Many risk variants have been identified, but the interpretation remains challenging. We investigated the genetic distribution of AMD-associated risk variants in a large European consortium, calculated attributable and pathway-specific genetic risks, and assessed the influence of lifestyle on genetic outcomes.

DESIGN

Pooled analysis of cross-sectional data from the European Eye Epidemiology Consortium.

PARTICIPANTS

Seventeen thousand one hundred seventy-four individuals 45 years of age or older participating in 6 population-based cohort studies, 2 clinic-based studies, and 1 case-control study.

METHODS

Age-related macular degeneration was diagnosed and graded based on fundus photographs. Data on genetics, lifestyle, and diet were harmonized. Minor allele frequencies and population-attributable fraction (PAF) were calculated. A total genetic risk score (GRS) and pathway-specific risk scores (complement, lipid, extra-cellular matrix, other) were constructed based on the dosage of SNPs and conditional β values; a lifestyle score was constructed based on smoking and diet.

MAIN OUTCOME MEASURES

Intermediate and late AMD.

RESULTS

The risk variants with the largest difference between late AMD patients and control participants and the highest PAFs were located in ARMS2 (rs3750846) and CHF (rs570618 and rs10922109). Combining all genetic variants, the total genetic risk score ranged from -3.50 to 4.63 and increased with AMD severity. Of the late AMD patients, 1581 of 1777 (89%) showed a positive total GRS. The complement pathway and ARMS2 were by far the most prominent genetic pathways contributing to late AMD (positive GRS, 90% of patients with late disease), but risk in 3 pathways was most frequent (35% of patients with late disease). Lifestyle was a strong determinant of the outcome in each genetic risk category; unfavorable lifestyle increased the risk of late AMD at least 2-fold.

CONCLUSIONS

Genetic risk variants contribute to late AMD in most patients. However, lifestyle factors have a strong influence on the outcome of genetic risk and should be a strong focus in patient management. Genetic risks in ARMS2 and the complement pathway are present in most late AMD patients but are mostly combined with risks in other pathways.

Intractable Ocular Diseases and Treatment Progress

In recent years, with the aging of the population and the frequent use of electronic devices, many eye diseases have shown a linear upward trend, such as dry eye disease, glaucoma, cataract, age-related macular degeneration, and diabetic retinopathy. These diseases are often chronic and difficult to cure. Based on the structure and barrier of the human eye, this review describes the pathogenesis and treatments of several intractable eye diseases and summarizes the advanced ocular drug delivery systems to provide new treatment ideas for these diseases. Finally, we also look forward to the prospect of RNAi therapy in the treatment of eye diseases.

Autophagy Upregulation by the TFEB Inducer Trehalose Protects against Oxidative Damage and Cell Death Associated with NRF2 Inhibition in Human RPE Cells

Trehalose is a natural dietary molecule that has shown antiaging and neuroprotective effects in several animal models of neurodegenerative diseases. The role of trehalose in the management of age-related macular degeneration (AMD) is yet to be investigated and whether trehalose could be a remedy for the treatment of diseases linked to oxidative stress and NRF2 dysregulation. Here, we showed that incubation of human retinal pigment epithelial (RPE) cells with trehalose enhanced the mRNA and protein expressions of TFEB, autophagy genes ATG5 and ATG7, as well as protein expressions of macroautophagy markers, LC3B and p62/SQTM1, and the chaperone-mediated autophagy (CMA) receptor LAMP2. Cathepsin D, a hydrolytic lysosomal enzyme, was also increased by trehalose, indicating higher proteolytic activity. Moreover, trehalose upregulated autophagy flux evident by an increase in the endogenous LC3B level, and accumulation of GFP-LC3B puncta and free GFP fragments in GFP-LC3 - expressing cells in the presence of chloroquine. In addition, the mRNA levels of key molecular targets implicated in RPE damage and AMD, such as vascular endothelial growth factor- (VEGF-) A and heat shock protein 27 (HSP27), were downregulated, whereas NRF2 was upregulated by trehalose. Subsequently, we mimicked in vitro AMD conditions using hydroquinone (HQ) as the oxidative insult on RPE cells and evaluated the cytoprotective effect of trehalose compared to vehicle treatment. HQ depleted NRF2, increased oxidative stress, and reduced the viability of cells, while trehalose pretreatment protected against HQ-induced toxicity. The cytoprotection by trehalose was dependent on autophagy but not NRF2 activation, since autophagy inhibition by shRNA knockdown of ATG5 led to a loss of the protective effect. The results support the transcriptional upregulation of TFEB and autophagy by trehalose and its protection against HQ-induced oxidative damage in RPE cells. Further investigation is, therefore, warranted into the therapeutic value of trehalose in alleviating AMD and retinal diseases associated with impaired NRF2 antioxidant defense.

NEI-Supported Age-Related Macular Degeneration Research: Past, Present, and Future

Purpose

To review past and current National Eye Institute (NEI)–supported age-related macular degeneration (AMD) activities and initiatives and preview upcoming coordinated efforts for studying AMD.

Methods

We conducted and summarized a portfolio analysis and literature review of NEI intramural and extramural AMD activities.

Results

The NEI supports a broad range of AMD research, both by individual independent investigators as well as through networks and consortia. The International AMD Genomics Consortium, Age-Related Eye Disease Study, Age-Related Eye Disease Study 2 (AREDS2), and Comparison of AMD Treatments Trial legacy work probed the complex genetics, clinical presentation, and standards of patient care, respectively. The NEI AMD Pathobiology Working Group identified gaps and opportunities for future research efforts. The AMD Ryan Initiative Study and clinical trials testing the efficacies of minocycline to modulate retinal microglia activity and induced pluripotent stem cells–derived retinal pigmented epithelium (RPE) patch implants to rescue photoreceptor cell death are among the future directions for NEI-supported AMD research. Finally, NEI commissioned the creation of AREDS2 participant-derived induced pluripotent stem cell (iPSC) lines linked to their associated genomic and phenotypic datasets. These datasets will also be linked to the data obtained using their associated iPSC-derived cells (RPE, retina, choroid) and made publicly available.

Conclusions

Investments by NEI for AMD research will continue to provide invaluable resources to investigators committed to addressing this complex blinding disease and other retinal degenerative diseases.

Translational Relevance

NEI now stands poised to expand the resources available to clinical investigators to uncover disease mechanisms and move experimental therapies into clinical trials.

COLORADO AGE-RELATED MACULAR DEGENERATION REGISTRY: Design and Clinical Risk Factors of the Cohort

PURPOSE

To study new and existing risk factors related to age-related macular degeneration (AMD) phenotypes in a Colorado cohort.

METHODS

Age-related macular degeneration was categorized into early, intermediate, or advanced forms. Controls (n = 180) were patients with cataract and no AMD. Demographic and clinical data were gathered by patient interview and verified by chart review. Image data were reviewed by vitreoretinal specialists. Statistical analysis included univariable and multivariate logistic regression analysis (P < 0.05).

RESULTS

Among the 456 patients with AMD, 157 (34.4%), 80 (17.6%), and 219 (48.0%) had the early/intermediate, geographic atrophy, and neovascular forms of the disease, respectively. Adjusted for age, African-American race was associated with a reduced risk of early/intermediate (adjusted odds ratio [AOR] = 0.08, confidence interval [CI] = 0.01-0.67) and neovascular AMD (AOR = 0.15, CI = 0.03-0.72). A family history of AMD was a risk factor for early/intermediate (AOR = 4.08, CI = 2.30-7.25), geographic atrophy (AOR = 8.62, CI = 3.77-19.7), and neovascular AMD (AOR = 3.76, CI = 2.16-6.56). A history of asthma was related to the early/intermediate form of AMD (AOR = 2.34, CI = 1.22-4.46).

CONCLUSION

Studying AMD in specific populations may reveal novel risk factors such as our finding of a relationship between asthma history and AMD.

Low Birth Weight Is Linked to Age-Related Macular Degeneration: Results From the Population-Based Gutenberg Health Study (GHS)

Purpose

This study analyzed whether low birth weight is linked to prevalence and incidence of age-related maculopathy (AMD) in adulthood.

Methods

The Gutenberg Health Study (GHS) is a population-based, observational cohort study in Germany. GHS participants at an age from 35 to 74 years were included. An ophthalmologic examination with fundus photography was carried out. Fundus photographs were graded according to the Rotterdam Grading Scheme for AMD at baseline and at the 5-year follow-up examination. Participants were divided into three different birth weight groups (low: <2500 g; normal: 2500-4000 g; and high: >4000 g). Poisson regression analysis with adjustment for several confounders was used to assess associations between birth weight and AMD prevalence (overall, early, late AMD) and 5-year cumulative incidence.

Results

Overall, 6492 participants were included (3538 female, aged 50.7 ± 10.4 years). Prevalence of total AMD was highest in the low birth weight group (11.2%; 40/358) compared to the normal birth weight group (6.5%; 346/5328) and the high birth weight group (8.4%; 68/806). Low birth weight was associated with overall AMD prevalence (prevalence ratio [PR] = 1.54, P = 0.006), and in particular with early AMD prevalence (PR = 1.52; P = 0.01). No association was observed between low birth weight and cumulative 5-year incidence of AMD.

Conclusions

Our analyses indicate that low birth weight may lead to higher prevalence of retinal diseases in later life, as we observed for AMD. Our results are limited due to missing data and loss to follow-up, but may be a first hint that AMD has one of its origins in early life.

Optometry Australia's chairside reference for the diagnosis and management of age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in people over the age of 50 years in Australia. Optometry Australia has developed this AMD chairside reference in consultation with a member-based working group comprised of experienced practitioners. It provides an evidence-based approach to current best practice in the diagnosis and management of AMD. Optometrists should be competent in assessing patients with or at risk of developing AMD, so that they are able to provide evidence-based management including appropriate communication, diagnosis and referral when indicated. This AMD chairside reference covers risk factors for the development of AMD or progression to late-stage AMD; the current clinical classification of AMD; common signs and symptoms; optometric assessment including ocular imaging and biomarkers; differential diagnoses; and management of early, intermediate and late AMD. Optometry Australia's chairside reference is intended as a general guide for optometrists, and is not a formal management protocol.

Age-Related Macular Degeneration and Associated Risk Factors in the Population-Based Study of Health in Pomerania (SHIP-Trend)

Background

Age-related macular degeneration (AMD) is the leading cause of visual impairment in developed countries, especially in the older population. The Study of Health in Pomerania (SHIP) is a population-based study designed to investigate risk factors and clinical disorders in the general population. In the present study, we analysed the AMD prevalence and risk factors in the north-eastern German population.

Material/Methods

From 2008 to 2012, we collected data among participants ages 29–79 years. The study population consisted of 4420 individuals. Non-mydriatic retinal photographs were taken of 3934 participants. AMD stages were graded according to the Rotterdam Classification System and the International Classification System.

Results

Photographs from 1854 participants were available for grading. The baseline examinations showed small hard drusen (<63 μm, stage 0b and 0c) were present in 10.7% of the participants (stage 0b in 7.5% and stage 0c in 3.2%). Earliest signs of AMD were detected in 28.68% (stage 0b in 7.5% and stage 1b in 21.18%). Late AMD (geographic atrophy and neovascular AMD, stages 4a and 4b) were identified in 0.43% (stage 4a in 0.16% and stage 4b 0.27%). Risk of AMD increased significantly with age and higher body mass index, waist circumference, hip circumference, and weight-waist-ratio. Smoking, sex, systolic and diastolic blood pressure, HbA1c, cholesterol, HDL-cholesterol, LDL-cholesterol, and triglyceride were not associated with AMD in this study.

Conclusions

The prevalence of AMD increases with age and obesity-associated factors. These results must be verified in the follow-up. Data concerning the incidence of AMD will be available after the 5- and 10-year follow-ups.

Artemisinin Protects Human Retinal Pigmented Epithelial Cells Against Hydrogen Peroxide-induced Oxidative Damage by Enhancing the Activation of AMP-active Protein Kinase

Dry age-related macular degeneration (AMD), a leading cause of blindness in aged population, is directly associated with oxidative stress induced damage of the retinal pigmented epithelial (RPE) cells. In the current study, we investigated the role of AMPK in the protective effect of artemisinin, an FDA approved anti-malarial Chinese herbal drug, on RPE cell line D407, against H₂O₂ induced oxidative stress. Our results showed that artemisinin promoted the survival of D407 cells from H₂O₂. Artemisinin reduced intracellular ROS generation and oxidative stress, decreased LDH release and the loss of mitochondrial membrane potential in D407 cells treated with H₂O₂. Western blotting showed that artemisinin concentration- and time-dependently stimulated the phosphorylation of AMP-activated protein kinase (AMPK) in D407 cells while AMPK inhibitor Compound C or knock-down of AMPK by si-RNA, inhibited the survival protective effect of artemisinin. More importantly, artemisinin produced a similar protective effect in primary cultured retinal pigment cells which was also blocked by inhibitors of AMPK. Taken together, these results suggested that artemisinin promotes survival of human retinal pigment cells against H₂O₂-induced cell death at least in part through enhancing the activation of AMPK. Therefore, artemisinin may be a beneficial therapeutic candidate for the treatment of age-related diseases, including retinal disorders like AMD.

Systemic activation of the complement system in patients with advanced age-related macular degeneration

Purpose:

To examine the role of systemic activation of the complement system (assessed by levels of circulating C3a, Ba, and sC5b-9) in patients (n = 122) with advanced age-related macular degeneration, geographic atrophy, and neovascular age-related macular degeneration, compared with cataract controls (n = 27).

Methods:

Plasma complement factors were measured using enzyme-linked immunosorbent assays. Statistical analysis included univariate and multivariate logistic regression (p < 0.05).

Results:

Adjusted for age, the odds ratios of C3a and sC5b-9 for any advanced age-related macular degeneration were 1.78 (95% confidence interval = 1.16–2.73, p < 0.01) and 1.20 (95% confidence interval = 1.04–1.39, p = 0.01), respectively. We found a significantly elevated adjusted odds ratio of C3a (adjusted odds ratio = 1.71, 95% confidence interval = 1.12–2.60, p = 0.01) and sC5b-9 (adjusted odds ratio = 1.22, 95% confidence interval = 1.04–1.43, p = 0.01) for neovascular age-related macular degeneration. Adjusted for age, neither C3a, sC5b-9, nor Ba were associated with geographic atrophy.

Conclusion:

We suggest a role for elevated plasma levels of C3a and sC5b-9 in patients with neovascular age-related macular degeneration. The study’s results reinforce the need for more investigation to assess the impact of therapeutic interventions targeted at the complement signaling pathways in age-related macular degeneration.

Genetic risk score has added value over initial clinical grading stage in predicting disease progression in age-related macular degeneration

Several prediction models for progression of age-related macular degeneration (AMD) have been developed, but the added value of using genetic information in those models in addition to clinical characteristics is ambiguous. In this prospective cohort study, we explored the added value of genetics using a genetic risk score (GRS) based on 52 AMD-associated variants, in addition to the clinical severity grading at baseline as quantified by validated drusen detection software, to predict disease progression in 177 AMD patients after 6.5 years follow-up. The GRS was strongly associated with the drusen coverage at baseline (P < 0.001) and both the GRS and drusen coverage were associated with disease progression. When the GRS was added as predictor in addition to the drusen coverage, R² increased from 0.46 to 0.56. This improvement by the GRS was predominantly seen in patients with a drusen coverage <15%. In patients with a larger drusen coverage, the GRS had less added value to predict progression. Thus, genetic information has added value over clinical characteristics in predicting disease progression in AMD, but only in patients with a less severe disease stage. Patients with a high GRS should be made aware of their risk and could be selected for clinical trials for arresting progression.

The cost-effectiveness of systematic screening for age-related macular degeneration in South Korea

Background

Interventions that can facilitate early diagnosis of age-related macular degeneration (AMD) will facilitate early treatment and improve clinical outcomes but there has been concerns about additional medical costs to the health care system. An examination through a retina fundus photography by a non-specialist has been suggested as a potential cost-effective alternative to a direct examination by a specialist, but limited scientific data exists on the cost-effectiveness of screening strategies for AMD. Our objective is to conduct an economic evaluation of various population-wide screening strategies for AMD among the South Korean population.

Methods and findings

Using a Markov cohort model, we evaluated the cost-effectiveness of four AMD screening strategies (opportunistic examination, opportunistic treatment, systematic photography, and systematic examination) in comparison with status quo (no screening) for South Korean adults. We projected a life time horizon to study a hypothetical cohort of 100,00 persons of age 40 with and without AMD at baseline. The outcome measures were quality-adjusted life-years (QALYs) gained, cost from the societal perspective, and the incremental cost-effectiveness ratio (ICER) of each strategy. Interventions were evaluated at a willingness-to-pay (WTP) threshold of 30,000,000 KRW ($27,538) per QALY gained. Deterministic and probabilistic sensitivity analyses were conducted to address the model uncertainty. Opportunistic examination was strongly dominated because it generated fewer expected QALYs but incurred greater expected cost than the other screening strategies. The mean lifetime expected costs were 289,013 KRW, 363,692 KRW, 9,351,964 KRW, and 12,309,783 KRW, and the mean QALYs gained were 37.73, 37.75, 40.47, 40.68, for no screening, opportunistic treatment, systematic photography, and systematic examination, respectively. The results were most sensitive to the utility weight of mild AMD, the probability of complication from treatment, the cost of being in mild AMD, and the probability of recovery from complication. After eliminating the two weakly dominated strategies, systematic photography was cost-effective at the ICER of 3,310,448 KRW per QALY in comparison to status quo.

Conclusions

Under the WTP threshold of 30,000,000 KRW per QALY, systematic photography is cost-effective for screening AMD in South Korean adults. Systematic examination by ophthalmologists generates more expected QALY and cost compared to systematic photography.

Risk factors for Age-related Macular Degeneration in a Greek population: The Thessaloniki Eye Study

PURPOSE

To assess the association of potential risk factors with early and late age-related macular degeneration (AMD) in the Thessaloniki Eye Study (TES) population Design: Population-based, cross-sectional study of subjects over age of 60 living in Thessaloniki, Greece Methods: Subjects without any AMD features and subjects with early and late AMD (neovascular AMD or geographic atrophy) were identified in the TES cohort using standardized procedures and masked grading of stereo color fundus photos. Demographic, lifestyle, systemic and other ophthalmic covariates were also collected during a detailed examination process. Their association with AMD was investigated using univariate and multivariate adjusted logistic regression models.

RESULTS

Among the 2108 participants with gradable photos, the grading process identified 1204 subjects with no AMD, 848 subjects with early AMD, and 56 subjects with late AMD (24 with geographic atrophy and 32 with neovascular AMD). In multivariate analysis, compared to no AMD, late AMD was positively associated with older age (OR:1.16; 95%CI:1.10-1.22 per year of age), current smoking (smoking vs. never smoking, OR:2.34; 95%CI:1.12-4.90), prior cataract surgery (cataract surgery vs. no cataract surgery OR:2.06; 95%CI:0.96-4.40), marital status (divorced/separated vs. married, OR:3.10; 95%CI:1.08-8.93) and with 60% lower odds when sleeping in the afternoon (yes vs. no, OR:0.40; 95%CI:0.22-0.72). Early AMD was positively associated with older age (OR: 1.03; 95%CI:1.01-1.05 per year of age) and negatively with higher pulse pressure (OR:0.99; 95%CI:0.98-0.99 per mmHg).

CONCLUSIONS

In TES, apart for well-known risk factors for AMD like age, smoking, and cataract surgery, two novel behavioral risk factors for prevalent late AMD were suggested. Sleeping in the afternoon was associated with 60% decreased odds for late AMD and 67% decreased odds for neovascular AMD. Being divorced/separated compared to married was associated with 3-fold higher odds for late AMD. Large longitudinal population-based studies will be necessary to further establish the potential late AMD risk effects of these two novel factors, to demonstrate potential implications of underlying pathogenetic mechanisms, and to explore preventive measures and therapeutic targets.

Complement System and Age-Related Macular Degeneration: Implications of Gene-Environment Interaction for Preventive and Personalized Medicine

Age-related macular degeneration (AMD) is the most common cause of visual loss in developed countries, with a significant economic and social burden on public health. Although genome-wide and gene-candidate studies have been enabled to identify genetic variants in the complement system associated with AMD pathogenesis, the effect of gene-environment interaction is still under debate. In this review we provide an overview of the role of complement system and its genetic variants in AMD, summarizing the consequences of the interaction between genetic and environmental risk factors on AMD onset, progression, and therapeutic response. Finally, we discuss the perspectives of current evidence in the field of genomics driven personalized medicine and public health.

Joint Contribution of Genetic Susceptibility and Modifiable Factors to the Progression of Age-Related Macular Degeneration over 10 Years: The Three Continent AMD Consortium Report

PURPOSE

To assess joint effects of genetic and modifiable factors on the 10-year progression of age-related macular degeneration (AMD).

DESIGN

Individual and pooled data analyses of 2 population-based cohorts.

PARTICIPANTS

Blue Mountains Eye Study (BMES) and Rotterdam Study (RS) participants (n = 835).

METHODS

Participants of the BMES and RS were followed up over 10 years or more. At baseline and follow-up visits, interviews using questionnaires and eye examinations with retinal photography were performed. Age-related macular degeneration was assessed by trained photographic graders and verified by retinal specialists. Genetic susceptibility to AMD meant carrying 2 or more risk alleles of the CFH or ARMS2 SNPs, or both (rs1061170 and rs10490924), relative to 0 or 1 risk allele. Discrete logistic regression models were used to investigate the joint associations of genetic susceptibility and either smoking, fish consumption, dietary intake of lutein-zeaxanthin, or combined environmental risk scores from the 3 modifiable factors with the risk of AMD progression. Odds ratios (ORs) with 95% confidence intervals (CIs) and synergy indexes are reported.

MAIN OUTCOME MEASURE

Ten-year progression of AMD, categorized as any (≥1 step) or 2-step (≥2 steps) progression on the Three Continent AMD Consortium 5-step severity scale.

RESULTS

Older age, the presence of AMD genetic susceptibility, and baseline AMD status were associated strongly with AMD progression (P < 0.0001). In analyses of pooled data, each additional score from the combined environmental risk scores was associated with an increased risk of 2-step progression over 10 years (OR, 1.26; 95% CI, 1.02-1.56). The copresence of AMD genetic susceptibility and combined risk score of 3 or more was associated with a substantially higher risk of 2-step progression compared with the presence of either factor alone. There was a significant synergistic effect (OR, 4.14; 95% CI, 1.07-15.95) and interaction (P = 0.025) between genetic susceptibility and environmental risk score of 3 or more.

CONCLUSIONS

Among persons with AMD genetic susceptibility and pre-existing early AMD lesions, presenting with high environmental risk scores from 3 modifiable factors (smoking, infrequent consumption of fish, low lutein-zeaxanthin intake) were associated with an increased risk of 2-step progression over 10 years.

Associations between fruit and vegetable, and antioxidant nutrient intake and age-related macular degeneration by smoking status in elderly Korean men

Background

Age-related macular degeneration (AMD) is one of the major causes of irreversible blindness. The objective of this study was to determine whether there is any relationship between dietary intake of fruits and vegetables (F&V) and antioxidant nutrients including carotenoids and AMD according to smoking status in elderly men.

Methods

We performed a cross-sectional analysis using nationally representative samples of elderly aged ≥ 65 years (n = 1414) from the Korea National Health and Nutrition Examination Survey (KNHANES, 2010–2012).

Results

The current smokers consumed less food in total, and, in particular, less cereals/potatoes/sugar products, fruits and vegetables than the nonsmokers and former smokers (p < 0.05). Intake of energy, thiamin, vitamin C, vitamin A, and β-carotene were significantly lower in the current smokers than in the nonsmokers and the former smokers. For current smokers, the ORs of the highest tertile compared with the lowest tertile were 0.36 (95% CI: 0.14–0.96, p for trend = 0.0576) for F&V, 0.32 (95% CI: 0.12–0.85, p for trend = 0.0561) for vitamin C, 0.23 (95% CI: 0.08–0.67, p for trend = 0.0038) for α-carotene, 0.13 (95% CI: 0.04–0.46, p for trend = 0.0003) for β-carotene after adjusting for confounding factors. In contrast, there was no association between antioxidant nutrient intake and AMD among the nonsmokers and former smokers.

Conclusions

These results suggest that increased consumption of fruits and vegetables containing antioxidant components such as vitamin C, α-carotene, and β-carotene may have a protective effect on AMD. These effects may be more evident among current smokers.

Prevention of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) compromises quality of life. However, the available therapeutic options are limited. This has led to the identification of modifiable risk factors to prevent the development or alter the natural course and prognosis of AMD. The identification and modification of risk factors has the potential for greater public health impact on reducing morbidity from AMD. Likewise, identifying the imaging clues and genetic clues could serve as a guide to recognizing the propensity for progression to severe and end stages of the disease. Several attempts, both successful and unsuccessful, have been made for interventions that could delay the progression of AMD. Of these, pharmacological interventions have shown promising results. The Age-Related Eye Disease Study 1 and 2 have shown the beneficial role of antioxidants in a selected group of patients.

Early and intermediate age-related macular degeneration: update and clinical review

Age-related macular degeneration (AMD) is the leading cause of irreversible central vision loss in developed countries. With the aging of population, AMD will become globally an increasingly important and prevalent disease worldwide. It is a complex disease whose etiology is associated with both genetic and environmental risk factors. An extensive decline in the quality of life and progressive need of daily living assistance resulting from AMD among those most severely affected highlights the essential role of preventive strategies, particularly advising patients to quit smoking. In addition, maintaining a healthy diet, controlling other risk factors (such as hypertension, obesity, and atherosclerosis), and the use of nutritional supplements (antioxidants) are recommendable. Genetic testing may be especially important in patients with a family history of AMD. Recently, unifying criteria for the clinical classification of AMD, defining no apparent aging changes; normal aging changes; and early, intermediate, and late AMD stages, are of value in predicting AMD risk of progression and in establishing recommendations for the diagnosis, therapeutic approach, and follow-up of patients. The present review is focused on early and intermediate AMD and presents a description of the clinical characteristics and ophthalmological findings for these stages, together with algorithms for the diagnosis and management of patients, which are easily applicable in daily clinical practice.

Prevalence and risk factors of epiretinal membranes: a systematic review and meta-analysis of population-based studies

OBJECTIVE

This study was to aggregate the prevalence and risks of epiretinal membranes (ERMs) and determine the possible causes of the varied estimates.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

The search strategy was designed prospectively. We searched PubMed, Embase and Web of Science databases from inception to July 2016. Reference lists of the included literatures were reviewed as well.

STUDY SELECTION

Surveys published in English language from any population were included if they had a population-based design and reported the prevalence of ERM from retinal photography with or without optical coherence tomography. Eligibility and quality evaluation was conducted independently by two investigators.

DATA EXTRACTION

The literature search generated 2144 records, and 13 population-based studies comprising 49 697 subjects were finally included. The prevalence of ERM and the ORs of potential risk factors (age, sex, myopia, hypertension and so on) were extracted.

RESULTS

The pooled age-standardised prevalence estimates of earlier ERM (cellophane macular reflex (CMR)), advanced ERM (preretinal macular fibrosis (PMF)) and any ERM were 6.5% (95% CI 4.2% to 8.9%), 2.6% (95% CI 1.8% to 3.4%) and 9.1% (95% CI 6.0% to 12.2%), respectively. In the subgroup analysis, race and photography modality contributed to the variation in the prevalence estimates of PMF, while the WHO regions and image reading methods were associated with the varied prevalence of CMR and any ERM. Meta-analysis showed that only greater age and female significantly conferred a higher risk of ERMs.

CONCLUSIONS

Our findings suggest that ERMs are relatively common among aged population. Race, image taking and reading methodology may play important roles in influencing the large variability of ERM prevalence estimates.

Complement factor H in AMD: Bridging genetic associations and pathobiology

Age-Related Macular Degeneration (AMD) is a complex multifactorial disease characterized in its early stages by lipoprotein accumulations in Bruch's Membrane (BrM), seen on fundoscopic exam as drusen, and in its late forms by neovascularization ("wet") or geographic atrophy of the Retinal Pigmented Epithelial (RPE) cell layer ("dry"). Genetic studies have strongly supported a relationship between the alternative complement cascade, in particular the common H402 variant in Complement Factor H (CFH) and development of AMD. However, the functional significance of the CFH Y402H polymorphism remains elusive. In this article, we critically review the literature surrounding the functional significance of this polymorphism. Furthermore, based on our group's studies we propose a model in which CFH H402 affects CFH binding to heparan sulfate proteoglycans leading to accelerated lipoprotein accumulation in BrM and drusen progression. We also review the literature on the role of other complement components in AMD pathobiologies, including C3a, C5a and the membrane attack complex (MAC), and on transgenic mouse models developed to interrogate in vivo the effects of the CFH Y402H polymorphism.

Early Age-related Macular Degeneration with Cardiovascular and Renal Comorbidities: An Analysis of the National Health and Nutrition Examination Survey, 2005-2008

PURPOSE

A cross sectional study was designed to examine the relationship of early age-related macular degeneration (AMD) with comorbidities of cardiovascular and renal conditions in the representative population using National Health and Nutrition Examination Survey (NHANES), 2005-2008.

METHODS

Participants (≥40 years) who underwent retinal photography were included. Early AMD was defined by the retinal digital images. The comorbidities were self-reported stroke and heart disease (HD), including angina pectoris (AP), coronary heart disease (CHD), congestive heart failure (CHF), and myocardial infarction (MI). Chronic kidney disease (CKD) was determined based on self-report, estimation of glomerular filtration rate (GFR), or the level of urine albumin.

RESULTS

The age-adjusted odds ratio (OR) and 95% CI for having early AMD for persons with the selected conditions were: 2.6 (1.9, 3.6) for any type of HD. When the conditions were considered separately, ORs (95% CIs) were: 2.0 (1.2, 3.4) for AP; 2.5 (1.6, 3.8) for CHD; 2.4 (1.6, 3.6) for MI; 2.3 (1.3, 3.9) for CHF; 3.3 (2.2, 5.0) for stroke; and 2.4 (1.8, 3.2) for CKD. Covariable-adjusted ORs (AOR) were attenuated for all examined conditions, but remained statistically significant. Having any single condition (AOR [95%CI]: 2.7 [1.5, 4.8]) was significantly associated with early AMD, as was having ≥ 2 conditions (AOR [95%CI]: 5.2 [3.0, 9.0]). The strongest association was between early AMD and the combination of HD and stroke (AOR [95% CI]: 6.3 [2.9, 13.8]).

CONCLUSION

Cardiovascular and renal comorbidities are associated with early AMD in a representative sample of the US general population.

Cigarette smoke induced autophagy-impairment regulates AMD pathogenesis mechanisms in ARPE-19 cells

Age related macular degeneration (AMD) is one of the leading causes of blindness. Genetics, environmental insult, and age-related factors all play a key role in altering proteostasis, the homeostatic process regulating protein synthesis, degradation and processing. These factors also play a role in the pathogenesis of AMD and it has been well established that cigarette smoking (CS) initiates AMD pathogenic mechanisms. The primary goal of this study is to elucidate whether CS can induce proteostasis/autophagy-impairment in retinal pigment epithelial (RPE) cells. In our preliminary analysis, it was found that cigarette smoke extract (CSE) induces accumulation of ubiquitinated proteins in the insoluble protein fraction (p < 0.01), which was subsequently mitigated through cysteamine (p < 0.01) or fisetin (p < 0.05) treatment. Further, it was verified that these CSE induced ubiquitinated proteins accumulated in the peri-nuclear spaces (p<0.05) that were cleared- off with cysteamine (p < 0.05) or fisetin (p < 0.05). Moreover, CSE-induced aggresome-formation (LC3B-GFP and Ub-RFP co-localization) and autophagy-flux impairment was significantly (p<0.01) mitigated by cysteamine (p<0.05) or fisetin (p<0.05) treatment, indicating the restoration of CSE-mediated autophagy-impairment. CSE treatment was also found to induce intracellular reactive oxygen species (ROS, p < 0.001) while impacting cell viability (p < 0.001), which was quantified using CMH2DCFDA-dye (ROS) and MTS (proliferation) or propodium iodide staining (cell viability) assays, respectively. Moreover, cysteamine and fisetin treatment ameliorated CS-mediated ROS production (p < 0.05) and diminished cell viability (p < 0.05). Lastly, CSE was found to induce cellular senescence (p < 0.001), which was significantly ameliorated by cysteamine (p < 0.001) or fisetin (p < 0.001). In conclusion, our study indicates that CS induced proteostasis/autophagy-impairment regulates mechanisms associated with AMD pathogenesis. Moreover, autophagy-inducing drugs such as cysteamine or fisetin can ameliorate AMD pathogenesis mechanisms that warrant further investigation in pre-clinical murine models.

[Multifocal electroretinography for therapeutic effect evaluation of intravitreal injection Lucentis for wet age-related macular degeneration]

OBJECTIVE

To evaluate the changes in retinal functions using multifocal electroretinography (mfERG) following intravitreal injection of Lucentis for treatment of wet age-related macular degeneration.

METHODS

This prospective study was conducted in 14 patients (9 men and 5 women, 14 eyes) with wet age-related macular degeneration receiving treatment with intravitreal injections of ranibizumab (Lucentis) in our hospital between October, 2014 and January, 2016. All the patients received the treatment following a 1+PRN protocol and after the initial injection, the patients were followed up monthly for 6 months to decide if additional injections were needed. The corrected visual acuity and mfERG findings of the patients were assessed before and at l, 3 and 6 months after the initial injection.

RESULTS

At the last follow-up, the patients received injections for a mean of 2.86∓1.58 times. The best corrected visual acuity (BCVA) at 1 month after the initial treatment was not significantly different from that before treatment (P=0.07), but showed significant improvements at 3 and 6 months (P<0.05). In mfERG, the implicit time of the 6 rings showed no significant decrease after the treatment, but the amplitude density of P1 and N1 in rings 1 and 2 improved significantly at 1, 3, and 6 months after the initial injection (P<0.05).

CONCLUSION

Multifocal electroretinography can serve as a useful modality for evaluating visual function changes in patients receiving intravitreal injection of Lucentis for wet age-related macular degeneration.

An epidemiological investigation of age-related macular degeneration in aged population in China: the Hainan study

Purpose

The aim of this study was to investigate the prevalence of age-related macular degeneration (AMD) and the risk factors in the residents aged ≥50 years in Hainan Province.

Methods

Random sampling was carried out in four separated cities in Hainan Province in 2015. All the subjects accomplished the standard questionnaire and ocular examinations. The diagnosis of AMD was performed based on the criteria proposed by Beckman Initiative for Macular Research Classification Committee.

Results

Three hundred and fifty-seven subjects (15.6%) were diagnosed with AMD, including 267 (11.7%) of early AMD, 64 (2.80%) of intermediate AMD and 24 (1.1%) of late AMD, respectively. The factors associated with the prevalence of AMD included age, educational level, smoking, outdoor activities and diet. The prevalence of AMD increased with age, lower educational level, smoking or less outdoor activities. The prevalence of AMD in those with a diet of meat or eggs was higher compared with a diet of vegetables or fish. The prevalence of early, intermediate and late AMD in the aged population in Hainan Province was 11.7, 2.8 and 1.1%, respectively.

Conclusions

Age and smoking were the risk factors for AMD, while the educational level and outdoor activities were the protective factors. Early AMD mostly occurred in those aged 50–59 years and 60–69 years, while intermediate and late AMD occurred in 70–79 years and older than 80 years.

Dietary Intakes of Eicosapentaenoic Acid and Docosahexaenoic Acid and Risk of Age-Related Macular Degeneration

PURPOSE

To evaluate the associations between intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the intermediate and advanced stages of age-related macular degeneration (AMD).

DESIGN

Prospective cohort study.

PARTICIPANTS

We followed 75 889 women from the Nurses' Health Study and 38 961 men from the Health Professionals Follow-Up Study who were at least 50 years old, from 1984 to 2012 and 1986 to 2010, respectively. Cohort participants are mostly white (≥95%).

METHODS

We assessed dietary intake by a validated food frequency questionnaire (FFQ) at baseline and every 4 years. We calculated cumulative average intakes of EPA and DHA from FFQs and also computed predicted erythrocyte and plasma scores directly from food intake using regression models. Cox proportional hazards models were used to compute the associations with AMD outcomes.

MAIN OUTCOME MEASURES

We confirmed 1589 incident intermediate and 1356 advanced AMD cases (primarily neovascular AMD) with a visual acuity of 20/30 or worse, owing primarily to AMD, by medical record review.

RESULTS

For intermediate AMD, the pooled hazard ratio (HR) between the 2 cohorts for DHA comparing the extreme quintiles of intake was 0.78 (95% confidence interval [CI], 0.66-0.92; P trend, 0.008) and for EPA + DHA was 0.83 (95% CI, 0.71-0.98; P trend, 0.03). The pooled HR for fatty fish, comparing ≥5 servings per week to almost never, was 0.61 (95% CI, 0.46-0.81; P trend, <0.001). For advanced AMD, the pooled HR for DHA was 1.01 (95% CI, 0.84-1.21; P trend, 0.75) and for fatty fish was 0.80 (95% CI, 0.59-1.08; P trend, 0.11). Secondary analyses using predicted erythrocyte and plasma scores of EPA and DHA yielded slightly stronger inverse associations for intermediate AMD and similar results for advanced AMD.

CONCLUSIONS

Higher intakes of EPA and DHA may prevent or delay the occurrence of visually significant intermediate AMD. However, the totality of current evidence for EPA and DHA and advanced AMD is discordant, though there was no association with advanced AMD in the present study.

Prevalence of ocular surface disease symptoms and risk factors in group of university students in Monterrey, Mexico

Background

The objective of this study was to determine the prevalence of symptoms of ocular surface disease and its relationship with associated risk factors in students from the University of Monterrey using Ocular Surface Disease (OSDI) questionnaire.

Methods

A cross-sectional survey was conducted between October and December 2014 to assess the prevalence and risk factors for ocular surface disease in a group of students from Universidad de Monterrey in Monterrey, Mexico. The severity of the disease was measured via the Ocular Surface Disease Index (OSDI) questionnaire.

Results

The OSDI average value was 26.85 ± 20.79 points, with 70.4% of students (579) had OSDI score higher than 12 points. Women had ocular surface disease 1.63 times more than men (OR 1.29, 95% CI 1.13,1.48). Students who used ophthalmic drops have an OR 2.00 (95% CI 1.65,2.40), and students who smoke have an OR 1.24 (95% CI 1.06,1.46). Use of contact lenses, hours in front of computer or history of refractive surgery has low-estimated effect on the probability of presenting an ocular disease.

Conclusions

University students have a prevalence of 70.4% of ocular surface disease (OSD). OSD was associated with gender (women have a higher prevalence), smoking and the use of eye drops. A program to modify these risk factors to reduce the prevalence is needed.

Genetic factors associated with the development of age-related macular degeneration

Age-related macular degeneration (AMD) affects the macula and is the leading cause of significant and irreversible central visual loss. It is the most common cause of visual loss in people aged more than 60 years. This disease affects 2.5 million individuals in Europe. AMD is caused by both environmental and genetic factors. Numerous risk factors have been reported, but the pathogenesis of AMD is complex and fairly understood. Age, female gender, obesity, race, education status, family history, hyperopia, iris color, cigarette smoking, previous cataract surgery, history of cardiovascular and cerebrovascular disease, diabetes, sunlight exposure and many other factors have been shown to be associated with AMD development. Scientific evidence shows that genes may play a role in the development of nearly 3 out of 4 cases of this devastating eye disease. The genes that have been shown to be associated with AMD are genes encoding complement system components such as CFH, C2, C3, CFB, and other.

Lutein Leads to a Decrease of Factor D Secretion by Cultured Mature Human Adipocytes

Purpose. Complement plays an important role in the pathogenesis of age related macular degeneration (AMD) and trials are currently being conducted to investigate the effect of complement inhibition on AMD progression. We previously found that the plasma level of factor D (FD), which is the rate limiting enzyme of the complement alternative pathway, was significantly decreased following lutein supplementation. FD is synthesized by adipose tissue, which is also the main storage site of lutein. In view of these findings we tested the hypothesis whether lutein could affect FD synthesis by adipocytes. Methods. A cell line of mature human adipocytes was incubated with 50 μg/mL lutein for 24 and 48 h, whereafter FD mRNA and protein expression were measured. Results. Lutein significantly inhibited adipocyte FD mRNA expression and FD protein release into adipocyte culture supernatants. Conclusions. Our earlier observations showing that a daily lutein supplement in individuals with early signs of AMD lowered the level of circulating FD might be caused by blocking adipocyte FD production.