Cigarette smoking and age-related macular degeneration in the EUREYE Study

Prevalence of age-related macular degeneration and retinal pseudodrusen in an elderly population. The ural very old study

PURPOSE

To assess the prevalence of age-related macular degeneration (AMD) and reticular pseudodrusen (RPD) in very old individuals.

METHODS

The population-based Ural Very Old Study consisted of 1526 (81.1%) out of 1882 eligible individuals aged 85 + years. All individuals living in the study regions and having an age of 85 + years were eligible for the study. The presence of AMD and RPDs was assessed on color fundus photographs, red-free fundus images, and optical coherence tomographic images.

RESULTS

The study included 932 (61.1% of 1526) individuals (age:88.6 ± 2.7 years) with available fundus images. Prevalence of any, early, intermediate and late AMD was 439/932 (47.1%; 95%CI:44.0,50.0), 126/932 (13.5%; 95% CI:11.0,16.0), 185/932 (19.8%; 95% CI:17.3,22.3) and 128/932 (13.7%; 95% CI:11.7,15.7), respectively. Neovascular AMD was present in 63 eyes (6.8%;95%CI:5.3,8.3) and geographic atrophy in 65 eyes (7.0%;95%CI:5.0,9.0). Higher prevalence of any AMD and late AMD was significantly correlated with urban region of habitation (OR:3.34; 95% CI:2.37,4.71; P < 0.001), and with older age (OR:1.12; 95% CI:1.04,1.19; P = 0.001), female sex (OR:1.63; 95%CI:1.02,2.60; P = 0.04), and urban region of habitation (OR:2.89; 95% CI:1.59,5.26; P < 0.001), respectively. RPDs (assessed in 889 (58.3%) study participants) were present in 220/889 participants (24.7%; 95%CI:21.7,27.7). Higher RPD prevalence was associated (multivariable analysis) with higher serum concentration of the rheumatoid factor (OR:1.15; 95% CI:1.04,1.28; P = 0.008), shorter axial length (OR:0.84;95%CI:0.71,0.00;P = 0.04), and higher degree of nuclear cataract (OR:1.06; 95% CI:1.01,1.12; P = 0.02). AMD was the main cause for vision impairment in 230 (24.7%) participants, for moderate-to-severe vision impairment in 75 (8.0%; 95% CI: 6.4, 10.0) individuals, and for blindness in 15 (1.6%; 95%CI: 0.8, 2.5) persons respectively.

CONCLUSIONS

In this ethnically mixed, very old population, AMD prevalence (any AMD:47.1%;late AMD:13.7%) was statistically independent of most systemic and ocular parameters. Higher RPD prevalence correlated with shorter axial length.

KEY MESSAGES

What is known The prevalence of age-related macular degeneration (AMD) has been explored in many studies and societies. Information is missing about its prevalence and associations in very old individuals. The same holds true for reticular pseudodrusen of the macula. What is new In an ethnically mixed, very old population in Bashkortostan / Russia, the prevalence of AMD (any AMD: 47.1%; late AMD:13.7%) was statistically independent of most systemic and ocular parameters. Higher prevalence of reticular pseudodrusen correlated with shorter axial length.

Incidence and risk factors of fellow-eyes wet conversion in unilateral neovascular age-related macular degeneration over 15-year follow-up

PURPOSE

Incidence and risk factors of fellow eye wet conversion in unilateral neovascular age-related macular degeneration (nAMD) over 15-years follow-up.

METHODS

This retrospective study reviewed 593 unilateral nAMD patients with a minimum of five years up to 15 years of follow-up. The demographic data, visual acuity, fellow eye nAMD conversion rate, and the number of anti-vascular endothelial growth factor (anti-VEGF) injections in the primary eye were evaluated. Also, the nAMD-converted fellow eyes were divided into two groups based on the time of conversion (less and more than two years from the first injection in the primary eye). Based on the data types, the T-test, Chi-square, and Mann-Whitney U test were used to analyze.

RESULTS

The total cases were 593 patients, and 248 eyes (41.82%) converted to nAMD in the mean interval of 34.92 ± 30.62 months. The males exhibited a predisposition to wet conversion at 2.54 years earlier than their female counterparts (P = 0.025). In all the converted fellow eyes, the mean age was 2.3 years higher at presentation in the group who converted within two years of follow-up in compared to eyes that converted after two years (79.82 ± 8.64 vs 77.51 ± 8.5 years, P = 0.035). Additionally, eyes converting within two years had a mean baseline LogMAR visual acuity of 0.44 ± 0.47, compared to 0.32 ± 0.41 for conversions after two years (P = 0.014).

CONCLUSION

This study reported that males showed a predisposition to fellow eye nAMD conversion at an earlier age. Additionally, there was a trend of faster fellow eye nAMD conversion in individuals with higher age and lower baseline visual acuity.

KEY MESSAGES

What is known • Certain risk factors may make the fellow eye of neovascular age-related macular degeneration (nAMD) more likely to progress to wet conversion. • Identifying these risk factors for fellow eye wet conversion can help prevent it, potentially preserving the patient's vision quality for a longer duration. • The studies on the incidence of wet conversion in the fellow eye have yielded controversial results. What is new • During the 15-year follow-up period, nearly half (47.58%) of the fellow eyes that underwent wet conversion did so within the initial two years following the wet conversion of the first eye. • Males showed a predisposition to fellow eye nAMD conversion at an earlier age. • There was a trend of faster fellow eye nAMD conversion in individuals with higher age and lower baseline visual acuity.

The Complement System as a Therapeutic Target in Retinal Disease

The complement cascade is a vital system in the human body's defense against pathogens. During the natural aging process, it has been observed that this system is imperative for ensuring the integrity and homeostasis of the retina. While this system is critical for proper host defense and retinal integrity, it has also been found that dysregulation of this system may lead to certain retinal pathologies, including geographic atrophy and diabetic retinopathy. Targeting components of the complement system for retinal diseases has been an area of interest, and in vivo, ex vivo, and clinical trials have been conducted in this area. Following clinical trials, medications targeting the complement system for retinal disease have also become available. In this manuscript, we discuss the pathophysiology of complement dysfunction in the retina and specific pathologies. We then describe the results of cellular, animal, and clinical studies targeting the complement system for retinal diseases. We then provide an overview of complement inhibitors that have been approved by the Food and Drug Administration (FDA) for geographic atrophy. The complement system in retinal diseases continues to serve as an emerging therapeutic target, and further research in this field will provide additional insights into the mechanisms and considerations for treatment of retinal pathologies.

Ophthalmologists' awareness of geographic atrophy: An Italian survey including 365 participants

PURPOSE

Geographic atrophy (GA) is a severe complication of age-related macular degeneration (AMD) and leads to irreversible visual decline. To date, no effective treatment is available for GA patients. However, a number of new therapies have recently been approved and several others are in the pipeline. This rapid evolution of prospects for GA patients requires constant updating of ophthalmologists' understanding of GA and its management so as to provide the appropriate treatment. For this reason, Società Italiana di Scienze Oftalmologiche (S.I.S.O.) has designed a specific survey to gauge the position of Italian ophthalmologists in this regard.

METHODS

The three hundred and sixty-five Italian ophthalmologists who agreed to take part received a seventeen-part questionnaire guaranteeing privacy and anonymity. The survey was compiled through an online portal and the results were sent directly to S.I.S.O. ETS. Two graders analyzed the data and recorded the results.

RESULTS

The results showed a high level of self-assessed awareness and understanding of GA, as well as considerable willingness to further improve knowledge of the disease. Most of the participants claimed to have effective rules of conduct in place for managing GA patients, including prompt response, involving a high prevalence of nutraceutical prescriptions and lifestyle recommendations.

CONCLUSIONS

This survey provided an overview of how GA patients are managed in Italy. The Italian ophthalmology community appears to be ready to adopt the upcoming treatments for GA.

Estrogen related receptor alpha: Potential modulator of age-related macular degeneration

To develop effective therapies for complex blinding diseases such as age-related macular degeneration (AMD), identification of mechanisms involved in its initiation and progression is needed. The estrogen-related receptor alpha (ESRRA) is an orphan nuclear receptor that regulates several AMD-associated pathogenic pathways. However, it has not been investigated in detail in the ocular posterior pole during aging or in AMD. This review delves into the literature highlighting the significance of ESRRA as a molecular target that may be important in the pathobiology of AMD, and discusses data available supporting the targeting of this receptor signaling pathway as a therapeutic option for AMD.

Resveratrol and quercetin protect from Benzo(a)pyrene-induced autophagy in retinal pigment epithelial cells

PURPOSE

This study aims to investigate the role of Resveratrol (RES) and quercetin (QR) treatments against Benzo(a)pyrene (B(a)p)-induced autophagy in retinal pigment epithelial cells.

METHODS

The IC50 doses of B(a)p, RES and QR in retinal pigment epithelial cells were determined by MTT assay and the relevant agents were administered singly or in combinations to ARPE-19 cells for 24 h. Occurrence of autophagy in the cells was verified by detection of autophagosomes using fluorescence microscope. Also, the mRNA expression levels of LC3 and Beclin 1 genes were analyzed by RT-PCR to collect further data on autophagy. Caspase-3 and IL-1β levels in lysed cells were analyzed by ELISA.

RESULTS

Autophagosomes were detected in B(a)p-treated ARPE-19 cell lines, as well as a 1.787-fold increase in LC3 mRNA expression levels. No autophagosome occurred in RES and QR treatments, and a significant decrease in their percentage amounts were observed in B(a)p + RES and B(a)p + QR. The mRNA expression levels of LC3 and Beclin 1 also supported these findings. B(a)p had no effect on Caspase-3 levels in ARPE-19 cells, but combined with RES and QR, it increased Caspase-3 levels significantly.IL-1β levels were higher in B(a)p, B(a)p + QR, B(a)p + RES, RES and QR than control group. This rise in IL-1β levels was correlated with suppression of mRNA expression levels of Beclin 1.

CONCLUSION

B(a)p exposure caused autophagy in ARPE-19 cells, but did not induce apoptosis. RES and QR treatments prevented B(a)p-induced autophagy. Therefore, RES and QR treatments showed protective effect against potential degenerative diseases caused by chronic exposure to B(a)p.

Indenopyrene and Blue-Light Co-Exposure Impairs the Tightly Controlled Activation of Xenobiotic Metabolism in Retinal Pigment Epithelial Cells: A Mechanism for Synergistic Toxicity

High energy visible (HEV) blue light is an increasing source of concern for visual health. Polycyclic aromatic hydrocarbons (PAH), a group of compounds found in high concentrations in smokers and polluted environments, accumulate in the retinal pigment epithelium (RPE). HEV absorption by indeno [1,2,3-cd]pyrene (IcdP), a common PAH, synergizes their toxicities and promotes degenerative changes in RPE cells comparable to the ones observed in age-related macular degeneration. In this study, we decipher the processes underlying IcdP and HEV synergic toxicity in human RPE cells. We found that IcdP-HEV toxicity is caused by the loss of the tight coupling between the two metabolic phases ensuring IcdP efficient detoxification. Indeed, IcdP/HEV co-exposure induces an overactivation of key actors in phase I metabolism. IcdP/HEV interaction is also associated with a downregulation of proteins involved in phase II. Our data thus indicate that phase II is hindered in response to co-exposure and that it is insufficient to sustain the enhanced phase I induction. This is reflected by an accelerated production of endogenous reactive oxygen species (ROS) and an increased accumulation of IcdP-related bulky DNA damage. Our work raises the prospect that lifestyle and environmental pollution may be significant modulators of HEV toxicity in the retina.

Geographic atrophy: pathophysiology and current therapeutic strategies

Geographic atrophy (GA) is an advanced stage of age-related macular degeneration (AMD) that leads to gradual and permanent vision loss. GA is characterized by the loss of photoreceptor cells and retinal pigment epithelium (RPE), leading to distinct atrophic patches in the macula, which tends to increase with time. Patients with geographic atrophy often experience a gradual and painless loss of central vision, resulting in difficulty reading, recognizing faces, or performing activities that require detailed vision. The primary risk factor for the development of geographic atrophy is advanced age; however, other risk factors, such as family history, smoking, and certain genetic variations, are also associated with AMD. Diagnosis is usually based on a comprehensive eye examination, including imaging tests such as fundus photography, optical coherence tomography (OCT), and fluorescein angiography. Numerous clinical trials are underway, targeting identified molecular pathways associated with GA that are promising. Recent approvals of Syfovre and Izervay by the FDA for the treatment of GA provide hope to affected patients. Administration of these drugs resulted in slowing the rate of progression of the disease. Though these products provide treatment benefits to the patients, they do not offer a cure for geographic atrophy and are limited in efficacy. Considering these safety concerns and limited treatment benefits, there is still a significant need for therapeutics with improved efficacy, safety profiles, and better patient compliance. This comprehensive review discusses pathophysiology, currently approved products, their limitations, and potential future treatment strategies for GA.

Through the Smoke: An In-Depth Review on Cigarette Smoking and Its Impact on Ocular Health

Smoking is a widespread and pervasive habit, impacting health across various care settings, including acute care, subacute care, home-based care, and long-term care. Smoking is a serious global public health concern that has been related to many chronic diseases. However, the effect of smoking on eye disorders has been less studied. Cigarette smoke contains a complex mixture of harmful constituents, including nicotine and toxic chemicals, which permeate the bloodstream, affecting ocular tissues. The oxidative stress and inflammation induced by smoking are central to its detrimental effects on ocular health. Age-related macular degeneration (AMD), a leading cause of vision loss, exhibits a strong association with smoking. Research consistently demonstrates that smokers face a heightened risk of both early and advanced AMD. Cataracts, another prevalent ocular condition, develop earlier and progress more rapidly in smokers. The oxidative stress on the lens and reduced antioxidants among smokers contribute to the increased severity of cataracts. Moreover, the health of the eyes may be compromised by smoking-related chemicals that reduce blood flow and/or hasten thrombus formation in ocular capillaries thus increasing the chance of acquiring glaucoma, cataracts, AMD, and Graves' eye disease. Beyond individual health concerns, the societal implications of smoking on ocular health are substantial, including increased healthcare costs and diminished quality of life for affected individuals. Understanding the underlying mechanisms can provide insights into potential therapeutic interventions for preventing and managing smoking-related ocular damage. Given the global prevalence of smoking, raising awareness about the ocular risks associated with smoking is crucial for promoting eye health. The review underscores the urgent need for comprehensive anti-smoking initiatives and smoking cessation programs to alleviate the burden of ocular diseases associated with smoking.

Effective health communication for age-related macular degeneration: An exploratory qualitative study

PURPOSE

Age-related macular degeneration (AMD) is a major cause of vision loss globally. Patients with AMD may not always understand or retain the information about AMD communicated by their eyecare practitioner. This study aims to explore the characteristics of effective health communication for AMD, from both patients' and eyecare practitioners' perspectives. The purpose is to provide a foundation for understanding how health communication for AMD could potentially be improved in the future.

METHODS

A total of 10 focus groups involving 17 patients with AMD and 17 optometrists were conducted via web conferencing. Each session was audio-recorded, transcribed and analysed using the Grounded Theory Methodology.

RESULTS

The five themes identified are as follows: (1) materials' quality, (2) materials' relevance, (3) contextualising for the individual, (4) contextualising for the disease and (5) support network. Participants expressed concern about the unrealistic yet common depiction of vision loss in AMD as a black patch overlying common visual scenes. They also preferred education materials tailored to a specific disease stage and the regular opportunity to ask or answer questions. Longer appointment durations and peer support (from family, friends or others with AMD) were also valued.

CONCLUSION

Optometrists are encouraged to focus on three over-arching dimensions when counselling patients with AMD in routine clinical practice: (1) curating and using disease and stage-specific, impactful education materials, (2) their chairside verbal communication techniques and (3) AMD-specific opportunities for care coordination among patient family and friends, peers and other multidisciplinary members of the care support team.

Alterations in Faecal and Serum Metabolic Profiles in Patients with Neovascular Age-Related Macular Degeneration

Neovascular age-related macular degeneration (nAMD) is a common and multifactorial disease in the elderly that may lead to irreversible vision loss; yet the pathogenesis of AMD remains unclear. In this study, nontargeted metabolomics profiling using ultra-performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry was applied to discover the metabolic feature differences in both faeces and serum samples between Chinese nonobese subjects with and without nAMD. In faecal samples, a total of 18 metabolites were significantly altered in nAMD patients, and metabolic dysregulations were prominently involved in glycerolipid metabolism and nicotinate and nicotinamide metabolism. In serum samples, a total of 29 differential metabolites were founded, involved in caffeine metabolism, biosynthesis of unsaturated fatty acids, and purine metabolism. Two faecal metabolites (palmitoyl ethanolamide and uridine) and three serum metabolites (4-hydroxybenzoic acid, adrenic acid, and palmitic acid) were selected as potential biomarkers for nAMD. Additionally, the significant correlations among dysregulated neuroprotective, antineuroinflammatory, or fatty acid metabolites in faecal and serum and IM dysbiosis were found. This comprehensive metabolomics study of faeces and serum samples showed that alterations in IM-mediated neuroprotective metabolites may be involved in the pathophysiology of AMD, offering IM-based nutritional therapeutic targets for nAMD.

Is there any association between the frequency of wet age-related macular degeneration recurrences and the seasons of the year?

PURPOSE

To investigate whether a seasonal distribution of the frequency of exudative age-related macular degeneration (wet AMD) recurrences exists.

METHODS

In total, 129 eyes with 171 recurrences in patients suffering from wet AMD were included in the study. All the patients had been treated with intravitreal anti-VEGF injections according to Pro Re Nata treatment regimen. Recurrence was defined as the re-detection of sub-retinal fluid, intraretinal fluid, and/or sub-macular hemorrhage in optical coherence tomography scans, after at least two consecutive monthly examinations with a "dry" macula. The year was divided in three 4-month periods (zone A: June-September, zone B: October-January, and zone C: February-May) based on the weather conditions prevailing in each period. Mean temperature and hours of sunlight exposure were the main weather markers recorded.

RESULTS

Eighty-two recurrences (48%) occurred during the period June-September, 50 (29.2%) during the period October-January, and 39 (22.8%) during the period February-May (Chi-square = 17.5, p < 0.001). Among the groups, neither patients' age (78 ± 8 years A, 76 ± 7 years B, and 79 ± 8 years C, p = 0.15) nor gender status (40% men A, 36% men B, and 51% men C, p = 0.35) differed significantly. Mean temperature was 27.6 ± 1.8 °C, 15.1 ± 4.6 °C, and 16.5 ± 4.4 °C in zones A, B, and C, respectively. Hours (h) of sunlight exposure (average hours/month) were 344 ± 34 h, 188 ± 42 h, and 223 ± 57 h in zones A, B, and C.

CONCLUSION

We demonstrated that the frequency of wet AMD recurrences is significantly elevated during the warmer months, possibly due to the higher levels of UV radiation and mean temperature. Further research is necessary to validate our findings.

Age-Related Macular Degeneration: An Exponentially Emerging Imminent Threat of Visual Impairment and Irreversible Blindness

Age-related macular degeneration (AMD) is a significant cause of blindness globally. With the exponential rise in the aging population, AMD is the third leading cause of visual impairment worldwide. Neovascular AMD (nAMD; Wet AMD) and geographical atrophy (GA, late-stage dry AMD) are the advanced AMD accountable for substantial cases of visual deterioration among the elderly. Our review of the literature depicted that notable risk factors include cigarette smoking, nutritional elements, cardiovascular disorders, and genetic markers, including genes regulating complement, lipid, and angiogenic pathways. Some studies have suggested a relative decline in the proportion of AMD cases in the last two decades attributable to novel diagnostic and therapeutic modalities. Accurate diagnosis is the result of a combination of clinical examination and imaging techniques, including retinal photography, angiography, and optical coherence tomography. The incorporation of dietary antioxidant supplements, explicitly lutein, slows the progression of the disease in advanced stages. The induction of vascular endothelial growth factor (VEGF) inhibitors in the treatment of neovascular AMD, often combined with other modalities, has shown an immensely favorable prognosis. Research to integrate gene therapy and regenerative techniques using stem cells is underway to further mitigate AMD-associated morbidity. It is imperative to establish screening and therapeutic guidelines for AMD to curtail the future social and financial burden and improve the diminishing quality of life among the elderly.

Retinal Microvasculature and Neural Changes and Dietary Patterns in an Older Population in Southern Italy

BACKGROUND

Like other parts of the body, the retina and its neurovascular system are also affected by age-related changes. The rising age of populations worldwide makes it important to study the pathologies related to age and their potential risk factors, such as diet and eating habits. The aim of this study was to investigate the predictive power of food groups versus retinal features among noninstitutionalized older adults from Southern Italy using a machine learning approach.

METHODS

We recruited 530 subjects, with a mean age of 74 years, who were drawn from the large population of the Salus in Apulia Study. In the present cross-sectional study, eating habits were assessed with a validated food frequency questionnaire. For the visual assessment, a complete ophthalmic examination and optical coherence tomography-angiography analyses were performed.

RESULTS

The analyses identified 13 out of the 28 food groups as predictors of all our retinal variables: grains, legumes, olives-vegetable oil, fruiting vegetables, other vegetables, fruits, sweets, fish, dairy, low-fat dairy, red meat, white meat, and processed meat.

CONCLUSIONS

Eating habits and food consumption may be important risk factors for age-related retinal changes. A diet that provides the optimal intake of specific nutrients with antioxidant and anti-inflammatory powers, including carotenoids and omega-3 fatty acids, could have beneficial effects.

Smoking and environmental tobacco smoke exposure: implications in ocular disorders

PURPOSE

This article aims to gather and review the available knowledge on several implications of smoking and environmental tobacco smoke (ETS) exposure in ocular disorders and provides pathomechanistic insights where applicable.

MATERIALS AND METHODS

PubMed and Scopus databases were searched for relevant studies on the association of smoking and ETS exposure with various ocular disorders. Studies with different evidence levels, e.g., in-vivo, case-control, cohort, and meta-analysis, were included.

RESULTS

Smoking is an established, modifiable risk factor in several ocular diseases, including cataract, age-related macular degeneration, and Graves' ophthalmopathy; smokers are subject to more severe disease courses and less favorable treatment outcomes. Uveitis is twice as likely in smokers; smoking may also delay its resolution. Smoking and ETS exposure are major risk factors for diseases of other organs, with associated ocular complications as well, such as diabetes mellitus. ETS exposure is also associated with ocular surface pathologies, including dry eye syndrome. In children, early-life ETS exposure and maternal smoking during pregnancy are strongly associated with refractive errors and strabismus. Currently, available data on potential risks attributable to ETS exposure regarding ocular diseases are scarce and, in some instances, controversial.

CONCLUSION

In addition to smoking, ETS exposure is also a significant public health concern with possible links to several ocular diseases. However, the level of education of at-risk populations in this regard does not match the strength of the evidence.

Emerging therapeutic strategies for unmet need in neovascular age-related macular degeneration

Neovascular age-related macular degeneration (nAMD) is a major cause of visual impairment and blindness. Anti-vascular endothelial growth factor (VEGF) agents, such as ranibizumab, bevacizumab, aflibercept, brolucizumab and faricimab have revolutionized the clinical management of nAMD. However, there remains an unmet clinical need for new and improved therapies for nAMD, since many patients do not respond optimally, may lose response over time or exhibit sub-optimal durability, impacting on real world effectiveness. Evidence is emerging that targeting VEGF-A alone, as most agents have done until recently, may be insufficient and agents that target multiple pathways (e.g., aflibercept, faricimab and others in development) may be more efficacious. This article reviews issues and limitations that have arisen from the use of existing anti-VEGF agents, and argues that the future may lie in multi-targeted therapies including alternative agents and modalities that target both the VEGF ligand/receptor system as well as other pathways.

Lifestyle Intervention Randomized Controlled Trial for Age-Related Macular Degeneration (AMD-Life): Study Design

Age-related macular degeneration (AMD) has a strong genetic basis, but environmental factors such as smoking and a healthy diet can decrease the genetic fate by up to 50%. Current guidelines for clinical management include recommendations for a healthy lifestyle and antioxidant supplementation. However, many ophthalmologists do not inform their patients of this AMD-beneficial lifestyle. An important reason is the lack of trust that transition of lifestyle will be feasible in persons of advanced age and lack of methodology to measure lifestyle or its biological effects. To address these issues, we set up the lifestyle intervention study AMD-Life. It aims to investigate whether personalized risk-profiling (including genetic testing) and/or additional coaching can motivate patients to change their lifestyle. It also explores which biomarkers best reflect lifestyle change beneficial for AMD. The first year is a three-arm, self-contained open-label randomized clinical trial. A total of 150 AMD patients aged 55-85 years were randomized into three arms: (A) merely standard recommendations; (B) A conditions plus personalized risk profiling based on genetics and lifestyle, (C) B conditions plus coaching. The second year tests sustainability of lifestyle changes without active intervention. AMD-Life can provide further insight into the relevance of these interventions for the clinical management of AMD.

Genome-wide association study and identification of systemic comorbidities in development of age-related macular degeneration in a hospital-based cohort of Han Chinese

Background: Age-related macular degeneration (AMD) is the main cause of severe vision loss in elderly populations of the developed world with limited therapeutic medications available. It is a multifactorial disease with a strong genetic susceptibility which exhibits the differential genetic landscapes among different ethnic groups. Methods: To investigate the Han Chinese-specific genetic variants for AMD development and progression, we have presented a genome-wide association study (GWAS) on 339 AMD cases and 3,390 controls of a Han Chinese population recruited from the Taiwan Precision Medicine Initiative (TPMI). Results: In this study, we have identified several single nucleotide polymorphisms (SNPs) significantly associated with AMD, including rs10490924, rs3750848, and rs3750846 in the ARMS2 gene, and rs3793917, rs11200638, and rs2284665 in the HTRA1 gene, in which rs10490924 was highly linked to the other variants based upon linkage disequilibrium analysis. Moreover, certain systemic comorbidities, including chronic respiratory diseases and cerebrovascular diseases, were also confirmed to be independently associated with AMD. Stratified analysis revealed that both non-exudative and exudative AMD were significantly correlated with these risk factors. We also found that homozygous alternate alleles of rs10490924 could lead to an increased risk of AMD incidence compared to homozygous references or heterozygous alleles in the cohorts of chronic respiratory disease, cerebrovascular disease, hypertension, and hyperlipidemia. Ultimately, we established the SNP models for AMD risk prediction and found that rs10490924 combined with the other AMD-associated SNPs identified from GWAS improved the prediction model performance. Conclusion: These results suggest that genetic variants combined with the comorbidities could effectively identify any potential individuals at a high risk of AMD, thus allowing for both early prevention and treatment.

Posterior Vitreous Detachment and Its Role in the Evolution of Dry to Wet Age Related Macular Degeneration

Purpose

To examine the state of the posterior vitreous in eyes with exudative age-related macular degeneration, AMD, non-exudative AMD and in normal eyes.

Study

This is a prospective, cross-sectional study.

Methods

B-scan ultrasonography and Optical Coherence Tomography, OCT were performed in 165 patients older than 65 years with any AMD and in 22 patients older than 65 years with normal eyes in order to diagnose the eyes with complete posterior vitreous detachment, PVD and the eyes with persistent central vitreomacular adhesion, VMA. All patients were selected from the outpatient clinic of the Ophthalmology Department in the University Hospital of Patras. Fundus Fluoroangiography, FFA was used in order to determine the development of exudative AMD from non-exudative AMD. Follow up time was 48 months.

Results

16/171 eyes with exudative AMD (9.36%) had complete PVD, and the rest 155/171 (90.64%) had central VMA. Eleven of 138 eyes with non-exudative AMD (7.97%) had complete PVD and the remaining 127 eyes (92.03%) had central VMA. During the 48 months of the study, 28 eyes, all with central VMA progressed to exudative AMD.

Conclusion

Vitreomacular adhesion is associated with both exudative and non-exudative AMD. Progression of the non-exudative eyes to exudative AMD seems to be lower in eyes with complete PVD. On the other hand, the progression of normal eyes to exudative AMD appears to be independent of the posterior vitreous status. Larger and longer studies need to replicate these findings and support the potential of a protective role of complete posterior vitreous detachment in the evolution of the disease.

Effects of Type 2 Diabetes Mellitus and Smoking on Changes in Corneal Endothelial Morphology and Cell Density

PURPOSE

The purpose of this study was to compare the corneal endothelial morphology and cell density of diabetic smokers and nonsmokers with 50 to 70 age-matched healthy subjects and to determine whether smoking increases the effects of type 2 diabetes mellitus (DM) on these corneal parameters.

METHODS

This prospective cohort study included 200 patients who were assigned to 4 groups, including smokers with type 2 DM (group 1), nonsmokers with type 2 DM (group 2), healthy smokers (group 3), and healthy nonsmokers (control group, group 4). Noncontact specular microscopy was used to measure central endothelial cell density (ECD), coefficient of variation of cell area, percentage of hexagonal cells, and central corneal pachymetry (CCT).

RESULTS

According to the ECD and CCT values ( P < 0.001 and P = 0.013, respectively), a significant difference was observed between the groups. The mean ECD was lowest in diabetic smokers (1917 ± 399 cells/mm 2 ). Healthy smokers and diabetic smokers had significantly lower ECD compared with the control group ( P = 0.03 and P < 0.001, respectively). Healthy smokers and diabetic smokers had significantly lower ECD compared with diabetic nonsmokers ( P = 0.012 and P < 0.001, respectively). The cornea was significantly thicker in the diabetic smokers than in the control group ( P = 0.013).

CONCLUSIONS

The coexistence of DM and smoking causes a significant decrease in ECD and an increase in CCT. Cigarette smoking is more harmful to corneal endothelial cells than DM alone.

Smoking Cessation May Reduce Risk of Visual Field Progression in Heavy Smokers

PRCIS

The earlier a person quits smoking the more likely is the optic nerve be spared from damage.

PURPOSE

To investigate the effect of smoking cessation on visual field (VF) progression in glaucoma.

METHODS

Primary open angle glaucoma patients with a minimum of 3 years follow-up and 5 VFs were included. Linear mixed models were used to investigate the effects of smoking on the rates of 24-2 VF mean deviation loss after adjusting for confounding factors. Cox proportional hazard regression was used to identify whether different levels of smoking intensity were associated with VF progression with respect to different duration of quitting.

RESULTS

Five hundred eleven eyes of 354 patients were included over the mean follow-up of 12.4 years. Mean baseline age (95% confidence interval) was 62.3 (61.2, 63.4) years. One hundred forty nine (42.1%) patients were smokers. In a multivariable model, smoking intensity was associated with faster VF loss (-0.06, 95% confidence interval (-0.10, -0.01) dB/year per 10 pack-years, P =0.01) among smokers. Heavy smokers (≥20 pack-years) who had quit ˂25 years prior had significantly greater odds of VF progression compared with never smokers (odds ratio=2.49 (1.01, 6.08); P =0.046). There was no significant difference in odds of VF progression in heavy smokers who had quit smoking more than 25 years compared with never smokers ( P =0.43). A significantly higher proportion of VF progression was found in heavy smokers who quit < 25 years compared with heavy smokers who quit ≥25 years by Kaplan-Meier analysis ( P =<0.001).

CONCLUSIONS

After ≥25 years of smoking cessation, the risk of VF progression in former heavy smokers becomes similar to never smokers. Long-term smoking cessation may be associated with lower VF progression in glaucoma patients.

A critical review on air pollutant exposure and age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of visual impairments and blindness worldwide in the elderly and its incidence strongly increases with ages. The etiology of AMD is complex and attributed to the genetic modifiers, environmental factors and gene-environment interactions. Recently, the impacts of air pollution on the development of eye diseases have become the new area of focus, and disordered air exposure combined with inadequate health management has caused problems for the eye health, such as dry eye, glaucoma, and retinopathy, while its specific role in the occurrence of AMD is still not well understood. In order to summarize the progress of this research field, we performed a critical review to summarize the epidemiological and mechanism evidence on the association between air pollutants exposure and AMD. This review documented that exposure to air pollutants will accelerate or worsen the morbidity and prevalence of AMD. Air pollutants exposure may change the homeostasis, interfere with the inflammatory response, and take direct action on the lipid metabolism and oxidative stress in the macula. More attention should be given to understanding the impact of ambient air pollution on AMD worldwide.

Molecular Genetic Mechanisms in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is among the leading causes of irreversible blindness worldwide. In addition to environmental risk factors, such as tobacco use and diet, genetic background has long been established as a major risk factor for the development of AMD. However, our ability to predict disease risk and personalize treatment remains limited by our nascent understanding of the molecular mechanisms underlying AMD pathogenesis. Research into the molecular genetics of AMD over the past two decades has uncovered 52 independent gene variants and 34 independent loci that are implicated in the development of AMD, accounting for over half of the genetic risk. This research has helped delineate at least five major pathways that may be disrupted in the pathogenesis of AMD: the complement system, extracellular matrix remodeling, lipid metabolism, angiogenesis, and oxidative stress response. This review surveys our current understanding of each of these disease mechanisms, in turn, along with their associated pathogenic gene variants. Continued research into the molecular genetics of AMD holds great promise for the development of precision-targeted, personalized therapies that bring us closer to a cure for this debilitating disease.

Adherence to the Mediterranean-Style Eating Pattern and Macular Degeneration: A Systematic Review of Observational Studies

Age-related macular degeneration (AMD) is a serious degenerative disease affecting the eyes, and is the main cause of severe vision loss among people >55 years of age in developed countries. Its onset and progression have been associated with several genetic and lifestyle factors, with diet appearing to play a pivotal role in the latter. In particular, dietary eating patterns rich in plant foods have been shown to lower the risk of developing the disease, and to decrease the odds of progressing to more advanced stages in individuals already burdened with early AMD. We systematically reviewed the literature to analyse the relationship between the adherence to a Mediterranean diet, a mainly plant-based dietary pattern, and the onset/progression of AMD. Eight human observational studies were analysed. Despite some differences, they consistently indicate that higher adherence to a Mediterranean eating pattern lowers the odds of developing AMD and decreases the risk of progression to more advanced stages of the disease, establishing the way for preventative measures emphasizing dietary patterns rich in plant-foods.

Biomarkers as Predictive Factors of Anti-VEGF Response

Age-related macular degeneration is the main cause of irreversible vision in developed countries, and intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections are the current gold standard treatment today. Although anti-VEGF treatment results in important improvements in the course of this disease, there is a considerable number of patients not responding to the standardized protocols. The knowledge of how a patient will respond or how frequently retreatment might be required would be vital in planning treatment schedules, saving both resource utilization and financial costs, but today, there is not an ideal biomarker to use as a predictive response to ranibizumab therapy. Whole blood and blood mononuclear cells are the samples most studied; however, few reports are available on other important biofluid samples for studying this disease, such as aqueous humor. Moreover, the great majority of studies carried out to date were focused on the search for SNPs in genes related to AMD risk factors, but miRNAs, proteomic and metabolomics studies have rarely been conducted in anti-VEGF-treated samples. Here, we propose that genomic, proteomic and/or metabolomic markers could be used not alone but in combination with other methods, such as specific clinic characteristics, to identify patients with a poor response to anti-VEGF treatment to establish patient-specific treatment plans.

[Epidemiological and clinical profile of age-related macular degeneration in Cameroon]

PURPOSE

To determine the epidemiological and clinical characteristics of age-related macular degeneration in patients in Yaoundé.

METHODOLOGY

A multicenter, analytical and cross-sectional study was carried out from March 2017 to June 2018 in four hospitals in the city of Yaoundé. Included were all consenting patients aged at least 40 years with an established diagnosis of AMD both clinically and by imaging. The data were analyzed with CSPro software version 7.0. Chi² and Student's "t" tests in univariate mode and logistic regression in multivariate mode were used with a significance of P≤5%.

RESULTS

Of the 9,989 patients who were seen during the 16-month study period, 38 met our inclusion criteria - a frequency of 0.4%. The sex ratio was 0.3, and the mean age was 68±11 years. As a function of geographic origin, AMD is more common in patients from the forest and mountain areas. The systemic comorbidities associated recorded were hypertension (47.4%) and diabetes (21.1%). After optical correction, 60 of 76 eyes (78.9%) had useful visual acuity according to WHO criteria, and the rate of blindness was 9.2%. Fundus examination revealed fewer lesions than optical coherence tomography, which demonstrated miliary drusen in 57 (75%) eyes, serous drusen in 27 (35.5%), retinal atrophy in 19 (25%) and neovascularization in 3 (3.9%). The clinical forms were dominated by age-related maculopathy, found in 45 eyes (69.2%), followed by atrophic AMD in 17 (26.2%) and finally by exudative AMD in 3 (4.6%), for a total of 65 out of 76 eyes. Age was related to the risk of MLA and atrophic AMD (P≤0.05).

CONCLUSION

AMD is an uncommon pathology in our setting, predominant in women over the age of 60 years.

Differential Mechanisms of Action and Efficacy of Vitamin E Components in Antioxidant Cytoprotection of Human Retinal Pigment Epithelium

The purpose of this study was to determine if different vitamin E components exhibit similar efficacy and mechanism of action in protecting Retinal pigment epithelium (RPE) cells from oxidative damage. We hypothesized that α-tocopherol (αT) is unique among vitamin E components in its cytoprotective mechanism of action against oxidative stress in RPE cells and that it requires protein synthesis for optimal antioxidant effect. We used cell viability assays, fluorescent chemical labeling of DNA and actin and immuno-labeling of the antioxidant proteins Nrf2 and Sod2 and of the tight junction protein, ZO-1, and confocal microscopy to determine the effects of αT and γT against oxidative stress in immortalized human RPE cells (hTERT-RPE). Using the four main vitamin E components, αT, γT, δ-tocopherol (δT) and α-tocotrienol (αTr), we ascertained that they exhibit similar, but not identical, antioxidant activity as αT when used at equimolar concentrations. In addition, we determined that the exposure time of RPE cells to α-tocopherol is critical for its ability to protect against oxidative damage. Lastly, we determined that αT, but not γT, partially requires the synthesis of new proteins within a 24-h period and prior to exposure to tBHP for optimal cytoprotection. We conclude that, unlike γT and δT, αT appears to be unique in its requirement for transport and/or signaling for it to be an effective antioxidant. As a result, more focus should be paid to which vitamin E components are used for antioxidant interventions.

Non-invasive testing for early detection of neovascular macular degeneration in unaffected second eyes of older adults: EDNA diagnostic accuracy study

BACKGROUND

Neovascular age-related macular degeneration is a leading cause of sight loss, and early detection and treatment is important. For patients with neovascular age-related macular degeneration in one eye, it is usual practice to monitor the unaffected eye. The test used to diagnose neovascular age-related macular degeneration, fundus fluorescein angiography, is an invasive test. Non-invasive tests are available, but their diagnostic accuracy is unclear.

OBJECTIVES

The primary objective was to determine the diagnostic monitoring performance of tests for neovascular age-related macular degeneration in the second eye of patients with unilateral neovascular age-related macular degeneration. The secondary objectives were the cost-effectiveness of tests and to identify predictive factors of developing neovascular age-related macular degeneration.

DESIGN

This was a multicentre, prospective, cohort, comparative diagnostic accuracy study in a monitoring setting for up to 3 years. A Cox regression risk prediction model and a Markov microsimulation model comparing cost-effectiveness of the index tests over 25 years were used.

SETTING

This took place in hospital eye services.

PARTICIPANTS

Participants were adults (aged 50-95 years) with newly diagnosed (within the previous 6 weeks) neovascular age-related macular degeneration in one eye and an unaffected second (study) eye who were attending for treatment injections in the first eye and who had a study eye baseline visual acuity of ≥ 68 Early Treatment Diabetic Retinopathy Study letters.

INTERVENTIONS

The index tests were Amsler chart (completed by participants), fundus clinical examination, optical coherence tomography, self-reported vision assessment (completed by participants) and visual acuity. The reference standard was fundus fluorescein angiography.

MAIN OUTCOME MEASURES

The main outcome measures were sensitivity and specificity; the performance of the risk predictor model; and costs and quality-adjusted life-years.

RESULTS

In total, 552 out of 578 patients who consented from 24 NHS hospitals (n = 16 ineligible; n = 10 withdrew consent) took part. The mean age of the patients was 77.4 years (standard deviation 7.7 years) and 57.2% were female. For the primary analysis, 464 patients underwent follow-up fundus fluorescein angiography and 120 developed neovascular age-related macular degeneration on fundus fluorescein angiography. The diagnostic accuracy [sensitivity (%) (95% confidence interval); specificity (%) (95% confidence interval)] was as follows: optical coherence tomography 91.7 (85.2 to 95.6); 87.8 (83.8 to 90.9)], fundus clinical examination [53.8 (44.8 to 62.5); 97.6 (95.3 to 98.9)], Amsler [33.7 (25.1 to 43.5); 81.4 (76.4 to 85.5)], visual acuity [30.0 (22.5 to 38.7); 66.3 (61.0 to 71.1)] and self-reported vision [4.2 (1.6 to 9.8); 97.0 (94.6 to 98.5)]. Optical coherence tomography had the highest sensitivity across all secondary analyses. The final prediction model for neovascular age-related macular degeneration in the non-affected eye included smoking status, family history of neovascular age-related macular degeneration, the presence of nodular drusen with or without reticular pseudodrusen, and the presence of pigmentary abnormalities [c-statistic 0.66 (95% confidence interval 0.62 to 0.71)]. Optical coherence tomography monitoring generated the greatest quality-adjusted life-years gained per patient (optical coherence tomography, 5.830; fundus clinical examination, 5.787; Amsler chart, 5.736, self-reported vision, 5.630; and visual acuity, 5.600) for the lowest health-care and social care costs (optical coherence tomography, £19,406; fundus clinical examination, £19,649; Amsler chart, £19,751; self-reported vision, £20,198; and visual acuity, £20,444) over the lifetime of the simulated cohort. Optical coherence tomography dominated the other tests or had an incremental cost-effectiveness ratio below the accepted cost-effectiveness thresholds (£20,000) across the scenarios explored.

LIMITATIONS

The diagnostic performance may be different in an unselected population without any history of neovascular age-related macular degeneration; the prediction model did not include genetic profile data, which might have improved the discriminatory performance.

CONCLUSIONS

Optical coherence tomography was the most accurate in diagnosing conversion to neovascular age-related macular degeneration in the fellow eye of patients with unilateral neovascular age-related macular degeneration. Economic modelling suggests that optical coherence tomography monitoring is cost-effective and leads to earlier diagnosis of and treatment for neovascular age-related macular degeneration in the second eye of patients being treated for neovascular age-related macular degeneration in their first eye.

FUTURE WORK

Future works should investigate the role of home monitoring, improved risk prediction models and impact on long-term visual outcomes.

STUDY REGISTRATION

This study was registered as ISRCTN48855678.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 8. See the NIHR Journals Library website for further project information.

Targeting Lysosomes to Reverse Hydroquinone-Induced Autophagy Defects and Oxidative Damage in Human Retinal Pigment Epithelial Cells

In age-related macular degeneration (AMD), hydroquinone (HQ)-induced oxidative damage in retinal pigment epithelium (RPE) is believed to be an early event contributing to dysregulation of inflammatory cytokines and vascular endothelial growth factor (VEGF) homeostasis. However, the roles of antioxidant mechanisms, such as autophagy and the ubiquitin-proteasome system, in modulating HQ-induced oxidative damage in RPE is not well-understood. This study utilized an in-vitro AMD model involving the incubation of human RPE cells (ARPE-19) with HQ. In comparison to hydrogen peroxide (H₂O₂), HQ induced fewer reactive oxygen species (ROS) but more oxidative damage as characterized by protein carbonyl levels, mitochondrial dysfunction, and the loss of cell viability. HQ blocked the autophagy flux and increased proteasome activity, whereas H₂O₂ did the opposite. Moreover, the lysosomal membrane-stabilizing protein LAMP2 and cathepsin D levels declined with HQ exposure, suggesting loss of lysosomal membrane integrity and function. Accordingly, HQ induced lysosomal alkalization, thereby compromising the acidic pH needed for optimal lysosomal degradation. Pretreatment with MG132, a proteasome inhibitor and lysosomal stabilizer, upregulated LAMP2 and autophagy and prevented HQ-induced oxidative damage in wildtype RPE cells but not cells transfected with shRNA against ATG5. This study demonstrated that lysosomal dysfunction underlies autophagy defects and oxidative damage induced by HQ in human RPE cells and supports lysosomal stabilization with the proteasome inhibitor MG132 as a potential remedy for oxidative damage in RPE and AMD.

A Systematic Review of Carotenoids in the Management of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) remains a leading cause of modifiable vision loss in older adults. Chronic oxidative injury and compromised antioxidant defenses represent essential drivers in the development of retinal neurodegeneration. Overwhelming free radical species formation results in mitochondrial dysfunction, as well as cellular and metabolic imbalance, which becomes exacerbated with increasing age. Thus, the depletion of systemic antioxidant capacity further proliferates oxidative stress in AMD-affected eyes, resulting in loss of photoreceptors, neuroinflammation, and ultimately atrophy within the retinal tissue. The aim of this systematic review is to examine the neuroprotective potential of the xanthophyll carotenoids lutein, zeaxanthin, and meso-zeaxanthin on retinal neurodegeneration for the purpose of adjunctive nutraceutical strategy in the management of AMD. A comprehensive literature review was performed to retrieve 55 eligible publications, using four database searches from PubMed, Embase, Cochrane Library, and the Web of Science. Epidemiology studies indicated an enhanced risk reduction against late AMD with greater dietary consumption of carotenoids, meanwhile greater concentrations in macular pigment demonstrated significant improvements in visual function among AMD patients. Collectively, evidence strongly suggests that carotenoid vitamin therapies offer remarkable synergic protection in the neurosensory retina, with the potential to serve as adjunctive nutraceutical therapy in the management of established AMD, albeit these benefits may vary among different stages of disease.

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.

Interlink between Inflammation and Oxidative Stress in Age-Related Macular Degeneration: Role of Complement Factor H

Age-related macular degeneration (AMD) heads the list of legal blindness among the elderly population in developed countries. Due to the complex nature of the retina and the variety of risk factors and mechanisms involved, the molecular pathways underlying AMD are not yet fully defined. Persistent low-grade inflammation and oxidative stress eventually lead to retinal pigment epithelium dysfunction and outer blood-retinal barrier (oBRB) breakdown. The identification of AMD susceptibility genes encoding complement factors, and the presence of inflammatory mediators in drusen, the hallmark deposits of AMD, supports the notion that immune-mediated processes are major drivers of AMD pathobiology. Complement factor H (FH), the main regulator of the alternative pathway of the complement system, may have a key contribution in the pathogenesis of AMD as it is able to regulate both inflammatory and oxidative stress responses in the oBRB. Indeed, genetic variants in the CFH gene account for the strongest genetic risk factors for AMD. In this review, we focus on the roles of inflammation and oxidative stress and their connection with FH and related proteins as regulators of both phenomena in the context of AMD.

Risk Stratification and Clinical Utility of Polygenic Risk Scores in Ophthalmology

Translational Relevance

Common genetic variants can be used to effectively stratify the risk of disease development and progression and may be used to guide screening, triaging, monitoring, or treatment thresholds.

Analysis of association of risk factors for age-related macular degeneration

PURPOSE

To evaluate the significance of risk factors and analyze their interrelationship in developing age-related macular degeneration (AMD).

MATERIALS AND DESIGN

This is a multicenter, cross-sectional study conducted in eight ophthalmology centers in Europe. The STARS (Simplified Thea AMD Risk-Assessment Scale) questionnaire was used to assess 12 risk factors grouped in four major categories. We used Welch's t-test/F ratios to determine statistically significant changes. The principal component analysis was done to investigate the association between risk factors.

RESULTS

There were 3297 participants included in our data analysis. Nineteen percent of patients had a high risk of developing AMD, whilst 45.92% and 34.85% had moderate and small risk, respectively. Atherosclerosis appeared as the most relevant risk indicator for AMD development (Cohen's d = 0.861). Tukey's post hoc analysis of the smoking variable showed that ex-smokers (p < 0.001) have a significantly high risk of developing AMD. The Welch's t-test showed pseudophakic patients have a higher risk of developing AMD than phakic ones. Then, we conducted the principal component analysis, which revealed a significant connection between smoking and male gender and between smoking and atherosclerosis. Pseudophakic patients were generally older and had more often myocardial infarction as compared to phakic patients. We showed that higher BMI, history of arterial hypertension, hypercholesterolemia, and atherosclerosis tend to occur together as risk factors for AMD.

CONCLUSION

Risk factors evaluated in our study should be considered for the development of AMD.

Age-Related Macular Degeneration: Role of Oxidative Stress and Blood Vessels

Age-related macular degeneration (AMD) is a common irreversible ocular disease characterized by vision impairment among older people. Many risk factors are related to AMD and interact with each other in its pathogenesis. Notably, oxidative stress and choroidal vascular dysfunction were suggested to be critically involved in AMD pathogenesis. In this review, we give an overview on the factors contributing to the pathophysiology of this multifactorial disease and discuss the role of reactive oxygen species and vascular function in more detail. Moreover, we give an overview on therapeutic strategies for patients suffering from AMD.

Superior Properties of N-Acetylcysteine Ethyl Ester over N-Acetyl Cysteine to Prevent Retinal Pigment Epithelial Cells Oxidative Damage

Oxidative stress plays a key role in the pathophysiology of retinal diseases, including age-related macular degeneration (AMD) and diabetic retinopathy, which are the major causes of irreversible blindness in developed countries. An excess of reactive oxygen species (ROS) can directly cause functional and morphological impairments in retinal pigment epithelium (RPE), endothelial cells, and retinal ganglion cells. Antioxidants may represent a preventive/therapeutic strategy and reduce the risk of progression of AMD. Among antioxidants, N-acetyl-L-cysteine (NAC) is widely studied and has been proposed to have therapeutic benefit in treating AMD by mitigating oxidative damage in RPE. Here, we demonstrate that N-acetyl-L-cysteine ethyl ester (NACET), a lipophilic cell-permeable cysteine derivative, increases the viability in oxidative stressed RPE cells more efficiently than NAC by reacting directly and more rapidly with oxidizing agents, and that NACET, but not NAC, pretreatment predisposes RPE cells to oxidative stress resistance and increases the intracellular reduced glutathione (GSH) pool available to act as natural antioxidant defense. Moreover, we demonstrate the ability of NACET to increase GSH levels in rats' eyes after oral administration. In conclusion, even if experiments in AMD animal models are still needed, our data suggest that NACET may play an important role in preventing and treating retinal diseases associated with oxidative stress, and may represent a valid and more efficient alternative to NAC in therapeutic protocols in which NAC has already shown promising results.

The Diagnosis and Treatment of Age-Related Macular Degeneration

BACKGROUND

Age-related macular degeneration (AMD) is thought to cause approximately 9% of all cases of blindness worldwide. In Germany, half of all cases of blindness and high-grade visual impairment are due to AMD. In this review, the main risk factors, clinical manifestations, and treatments of this disease are presented.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed for original articles and reviews, as well as on current position statements by the relevant specialty societies.

RESULTS

AMD is subdivided into early, intermediate, and late stages. The early stage is often asymptomatic; patients in the other two stages often have distorted vision or central visual field defects. The main risk factors are age, genetic predisposition, and nicotine consumption. The number of persons with early AMD in Germany rose from 5.7 million in 2002 to ca. 7 million in 2017. Late AMD is subdivided into the dry late form of the disease, for which there is no treatment at present, and the exudative late form, which can be treated with the intravitreal injection of VEGF inhibitors.

CONCLUSION

More research is needed on the dry late form of AMD in particular, which is currently untreatable. The treatment of the exudative late form with VEGF inhibitors is labor-intensive and requires a close collaboration of the patient, the ophthalmologist, and the primary care physician.

Role of complement factor B rs4151667 (L9H) polymorphisms and its interactional role with CFH Y402H and C3 rs2230199 (R102G) risk variants in age-related macular degeneration: a case control study

Background

Age-related Macular Degeneration (AMD) is a complex eye disease, which is genetically associated with different susceptibility loci. We planned to investigate the possible association of Complement Factor B (CFB) rs4151667 (L9H) variants and their possible interaction with Complement Factor H (CFH) Y402H and Complement factor 3 (C3) rs2230199 (R102G) in AMD.

Methods

This case-control association study included 216 advanced type AMD patients and 191 healthy individuals for evaluation. Extracted-DNA samples were genotyped for the polymorphic regions of CFB rs4151667 (L9H), CFH Y402H and C3 rs2230199 (R102G).

Results

The distribution of CFB rs4151667 (L9H) genotypes was not significantly different in the AMD patients compared to that of controls (P = 0.18). The AT genotype frequencies for CFB was non significantly lower in AMD group (6.5% vs. 13.1%, AOR = 0.49, CI = 0.23–1.04, P = 0.064(. The A allele of CFB rs4151667 (L9H) was found to be non-significantly lower in AMD patients. CFB rs4151667 (L9H) had no protective interactional effect against CFH (Y402H) and C3 (R102G) risk variants.

Conclusions

This study showed that the protective role of CFB rs4151667 (L9H) in AMD is not significant and it has no significant protective interactional effect against CFH (Y402H) and C3 (R102G) risk variants.

Serum vitamin D and age-related macular degeneration: Systematic review and meta-analysis

Vitamin D may be implicated in the pathophysiology of several ocular diseases, but its role in age-related macular degeneration (AMD) remains uncertain. We sought to review systematically the existing evidence to evaluate the association between serum 25-hydroxyvitamin D 25(OH)D levels and AMD. A four-database search (PubMed, ISI Web of Science, Cochrane, and Scopus) was performed from inception to May 2020 using the MeSH terms: ("Macular Degeneration" OR "Age-related macular degeneration" OR "Retinal degeneration" OR "Macula lutea") AND ("Vitamin D" OR "Ergocalciferols" OR "Cholecalciferol" OR "25-Hydroxyvitamin D"). Random-effects meta-analyses were performed to compute 1) the standard mean difference in 25(OH)D concentration between AMD and non-AMD patients and 2) the AMD risk according to serum 25(OH)D levels. Eighteen observational studies enrolling 75,294 patients after a selection process among 375 original abstracts were selected. No significant differences were found, but there appears to exist a trend for late AMD among subjects with a serum 25(OH)D level below 50 nmol/L (odds ratio, 1.8; 95% confidence interval: 1.00-3.24, P = 0.05). There is no clear evidence of a definitive association between serum 25(OH)D and AMD risk, mainly due to heterogeneity in study procedures and lack of longitudinal designs.

Immunization Against Oxidized Elastin Exacerbates Structural and Functional Damage in Mouse Model of Smoke-Induced Ocular Injury

Purpose

Age-related macular degeneration (AMD) is the leading cause of blindness in Western populations. While an overactive complement system has been linked to pathogenesis, mechanisms contributing to its activation are largely unknown. In aged and AMD eyes, loss of the elastin layer (EL) of Bruch's membrane (BrM) has been reported. Elastin antibodies are elevated in patients with AMD, the pathogenic significance of which is unclear. Here we assess the role of elastin antibodies using a mouse model of smoke-induced ocular pathology (SIOP), which similarly demonstrates EL loss.

Methods

C57BL/6J mice were immunized with elastin or elastin peptide oxidatively modified by cigarette smoke (ox-elastin). Mice were then exposed to cigarette smoke or air for 6 months. Visual function was assessed by optokinetic response, retinal morphology by spectral-domain optical coherence tomography and electron microscopy, and complement activation and antibody deposition by Western blot.

Results

Ox-elastin IgG and IgM antibodies were elevated in ox-elastin immunized mice following 6 months of smoke, whereas elastin immunization had a smaller effect. Ox-elastin immunization exacerbated smoke-induced vision loss, with thicker BrM and more damaged retinal pigment epithelium (RPE) mitochondria compared with mice immunized with elastin or nonimmunized controls. These changes were correlated with increased levels of IgM, IgG2, IgG3, and complement activation products in RPE/choroid.

Conclusions

These data demonstrate that SIOP mice generate elastin-specific antibodies and that immunization with ox-elastin exacerbates ocular pathology. Elastin antibodies represented complement fixing isotypes that, together with the increased presence of complement activation seen in immunized mice, suggest that elastin antibodies exert pathogenic effects through mediating complement activation.

Loss of Complement Factor H impairs antioxidant capacity and energy metabolism of human RPE cells

Polymorphisms in the Complement Factor H (CFH) gene, coding for the Factor H protein (FH), can increase the risk for age-related macular degeneration (AMD). AMD-associated CFH risk variants, Y402H in particular, impair FH function leading to complement overactivation. Whether this alone suffices to trigger AMD pathogenesis remains unclear. In AMD, retinal homeostasis is compromised due to the dysfunction of retinal pigment epithelium (RPE) cells. To investigate the impact of endogenous FH loss on RPE cell balance, we silenced CFH in human hTERT-RPE1 cells. FH reduction led to accumulation of C3, at both RNA and protein level and increased RPE vulnerability toward oxidative stress. Mild hydrogen-peroxide exposure in combination with CFH knock-down led to a reduction of glycolysis and mitochondrial respiration, paralleled by an increase in lipid peroxidation, which is a key aspect of AMD pathogenesis. In parallel, cell viability was decreased. The perturbations of energy metabolism were accompanied by transcriptional deregulation of several glucose metabolism genes as well as genes modulating mitochondrial stability. Our data suggest that endogenously produced FH contributes to transcriptional and metabolic homeostasis and protects RPE cells from oxidative stress, highlighting a novel role of FH in AMD pathogenesis.

Protection of human retinal pigment epithelial cells from oxidative damage using cysteine prodrugs

Age-related macular degeneration (AMD) is one of the major causes of vision loss in the elderly in most developed countries. Among other causes, oxidative stress in the retinal pigment epithelium (RPE) has been hypothesized to be a major driving force of AMD pathology. Oxidative stress could be treated by antioxidant administration into the RPE cells. However, to achieve high in-vivo efficacy of an antioxidant, it is imperative that the agent be able to penetrate the tissues and cells. Evidence suggests that lipophilicity governs cellular penetrance. Out of many antioxidant candidates, N-acetyl-L-cysteine (a prodrug of L-cysteine) (NAC) is a potent antioxidant as the bioavailability of the parent drug, L-cysteine, determines the production of glutathione; the universal antioxidant that regulates ROS. To increase the lipophilicity, four ester derivatives of N-acetylcysteine: N-acetylcysteine methyl ester, N-acetylcysteine ethyl ester, N-acetylcysteine propyl ester, and N-acetylcysteine butyl ester were synthesized. To mimic in vitro AMD conditions, hydroquinone, a component of cigarette smoke, was used as the oxidative insult. Cytosolic and mitochondrial protection against oxidative stress were tested using cytosolic and mitochondrial specific assays. The results provide evidence that these lipophilic cysteine prodrugs provide increased protection against oxidative stress in human RPE cells compared with NAC.

Nutrition and the aging retina: A comprehensive review of the relationship between nutrients and their role in age-related macular degeneration and retina disease prevention

Age-related macular degeneration (AMD) is the leading cause of severe vision loss in developed countries and is highly common among aging individuals. Considering the rate at which the global population is aging, the increasing prevalence of AMD and age-related eye disease is cause for concern. AMD is associated with the degeneration of the macula, the most central region of the retina, leading to a loss of central vision. A wide array of research has focused on the ability of lipid soluble nutrients to prevent and mitigate the harmful effects of AMD. These nutrients in question tend to be highly saturated within retinal tissues including the carotenoids lutein and zeaxanthin and the polyunsaturated fatty acid docosahexaenoic acid (DHA). Additionally, the unique presence of very long chain polyunsaturated fatty acids (VLCPUFAs, C24-C36) in the retina may be essential to prevent retinal degeneration as demonstrated by abnormal retinal functioning in the absence of these novel fatty acids. Existing literature has suggested that lutein, zeaxanthin and DHA consumption tend to enhance the health of the retina, protecting against the development of AMD. However, little improvement to the previously deteriorated retina is demonstrated and more research is required to understand the role of these nutrients in the retina and for the prevention of AMD. Considering the global impact of AMD and age-related eye disease, utilizing nutrients to prevent the formation of these debilitating diseases is a highly affordable and promising strategy.

The Light and the Dark of Early and Intermediate AMD: Cone- and Rod-Mediated Changes Are Linked to Fundus Photograph and FAF Abnormalities

Purpose

The purpose of this paper is to describe the extent to which scotopic and photopic measures of visual function predict color fundus photograph (CFP) and fundus autofluorescence (FAF) changes in early and intermediate nonexudative AMD.

Methods

Sixty-nine observers were recruited: 56 AMD patients (mean age, 73 ± 12.98 years) and 13 controls (mean age, 67.77 ± 9.72 years). A nonmydriatic retinal camera was used to obtain stereo fundus photographs and FAF images were recorded with a cSLO Heidelberg Spectralis HRA+OCT. Visual acuity (VA) was measured using an Early Treatment of Diabetic Retinopathy Study chart. Contrast sensitivity (CS) was assessed with a Pelli-Robson chart. Dark adaptation (DA) curves were recorded at 3° eccentricity using a PC-based technique. Analysis of these curves yielded five parameters: cone threshold (CT), cone time constant (CC), cone-rod break (α), slope of the second rod component (S2), and rod-rod break (β).

Results

Both cone and rod sensitivity recovery were grossly abnormal in the patients. The rod recovery slope (S2) most accurately predicted the fundus photograph-based grade and the FAF classification (ρ = 0.61 and ρ = 0.60, respectively; both P < 0.0001). CS showed a strong association with FAF (ρ = 0.50, P < 0.0001) and with fundus photograph-based grade (ρ = 0.38, P < 0.002). There was no correlation between VA and either imaging method.

Conclusions

Dynamic, rod-based measures most accurately reflect the severity of early AMD. Although less specific to AMD than DA changes, static photopic abnormalities such as CS also correspond with morphologic changes. Assessment of function in early AMD should include dynamic rod- and cone-mediated measurements of sensitivity recovery.

Prevalence and Associated Factors of Age-Related Macular Degeneration in a Russian Population: The Ural Eye and Medical Study

PURPOSE

To assess the prevalence of age-related macular degeneration (AMD) in a Russian population.

DESIGN

Population-based prevalence assessment.

METHODS

The Ural Eye and Medical Study was conducted in a rural and urban area in the Russian republic of Bashkortostan. The study included 5,899 participants aged 40+ years old. AMD, defined according to the Beckman Initiative for Macular Research, was assessed by fundus photographs and optical coherence tomographic images of 4,932 (83.6%) participants.

RESULTS

The prevalence of any AMD, early AMD, intermediate AMD, or late AMD, geographic atrophy, and neovascular AMD were 18.2% (95% confidence interval [CI], 16.8-19.6), 11.6% (95% CI, 10.4-12.8), 5.0% (95% CI, 4.2-5.8), 1.6% (95% CI, 1.1-2.0), 0.7% (95% CI, 0.4-1.0) and 0.9% (95% CI, 0.6-1.3), respectively, for individuals >55 years old. Applying an age limit of 40+ years for the AMD definition, prevalence of any AMD, early AMD, intermediate AMD, late AMD, geographic atrophy and neovascular AMD were 14.1% (95% CI, 13.1-15.1), 9.4% (95% CI, 8.6-10.2), 3.8% (95% CI, 3.2-4.3), 1.0% (95% CI, 0.7-1.2), 0.4% (95% CI, 0.2-0.6) and 0.5% (95% CI, 0.3-0.7), respectively, for individuals aged 40+ years. Higher AMD prevalence was correlated with older age (odds ratio [OR], 1.15; 95% CI, 1.13-1.16; P < 0.001), rural region (OR, 1.69; 95% CI, 1.32-2.17; P < 0.001), lower diabetes prevalence (OR, 0.56; 95% CI, 0.38-0.82; P = 0.003), and shorter axial length (OR, 0.89; 95% CI, 0.79-0.99; P = 0.04). AMD prevalence was not significantly (all P ≥ 0.20) correlated with any systemic parameter examined, except for lower prevalence of diabetes.

CONCLUSIONS

In this typical, ethnically mixed, urban and rural population from Russia, a higher prevalence for AMD was associated mainly with older age, rural region of habitation, shorter axial length, and lower prevalence of diabetes mellitus. The AMD prevalence was lower than in Europeans and higher than in East Asians.

Microvascular contributions to age-related macular degeneration (AMD): from mechanisms of choriocapillaris aging to novel interventions

Aging of the microcirculatory network plays a central role in the pathogenesis of a wide range of age-related diseases, from heart failure to Alzheimer's disease. In the eye, changes in the choroid and choroidal microcirculation (choriocapillaris) also occur with age, and these changes can play a critical role in the pathogenesis of age-related macular degeneration (AMD). In order to develop novel treatments for amelioration of choriocapillaris aging and prevention of AMD, it is essential to understand the cellular and functional changes that occur in the choroid and choriocapillaris during aging. In this review, recent advances in in vivo analysis of choroidal structure and function in AMD patients and patients at risk for AMD are discussed. The pathophysiological roles of fundamental cellular and molecular mechanisms of aging including oxidative stress, mitochondrial dysfunction, and impaired resistance to molecular stressors in the choriocapillaris are also considered in terms of their contribution to the pathogenesis of AMD. The pathogenic roles of cardiovascular risk factors that exacerbate microvascular aging processes, such as smoking, hypertension, and obesity as they relate to AMD and choroid and choriocapillaris changes in patients with these cardiovascular risk factors, are also discussed. Finally, future directions and opportunities to develop novel interventions to prevent/delay AMD by targeting fundamental cellular and molecular aging processes are presented.

Periodontal Diseases and Age-Related Macular Degeneration: Is There a Link? A Review

BACKGROUND

Age-related macular degeneration (AMD) induces irreversible loss of vision in older people. The exact physiopathology remains unclear, but numerous studies highlight the role of inflammation and multiple risk factors. Recent data show an altered periodontal condition subject to AMD. Periodontal diseases lead to the destruction of tooth-supporting tissues, mainly caused by the periodontal infection inducing a chronic inflammation. Periodontal diseases are known to be associated with several extraoral diseases such as diabetes, polyarthritis (rheumatoid arthritis), cardiovascular disease, and preeclampsia.

OBJECTIVES

To assess emerging evidence suggesting an association between periodontitis and AMD.

METHODS

To support this review, we performed a literature search using PubMed, Cochrane, and Google Scholar databases, completed by manual searches in periodontology journals. We included only the original studies published before July 2017 reporting data on periodontal diseases and AMD. No restrictions were made on the language.

RESULTS

Persons with AMD showed more periodontal diseases, fewer teeth, and more alveolar bone loss than those without AMD. Also, a significant association was observed between periodontal diseases and AMD, but only in the youngest individuals studied.

CONCLUSION

According to the studies included in this review, periodontal disease may be a plausible risk factor for AMD and may have a potential role in the earlier stages of this eye disease. Further studies should be encouraged for better understanding of this potential new relationship.

Treatments for dry age-related macular degeneration and Stargardt disease: a systematic review

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of visual loss in older people. Advanced AMD takes two forms, neovascular (wet) and atrophic (dry). Stargardt disease (STGD) is the commonest form of inherited macular dystrophy.

OBJECTIVE

To carry out a systematic review of treatments for dry AMD and STGD, and to identify emerging treatments where future NIHR research might be commissioned.

DESIGN

Systematic review.

METHODS

We searched MEDLINE, EMBASE, Web of Science and The Cochrane Library from 2005 to 13 July 2017 for reviews, journal articles and meeting abstracts. We looked for studies of interventions that aim to preserve or restore vision in people with dry AMD or STGD. The most important outcomes are those that matter to patients: visual acuity (VA), contrast sensitivity, reading speed, ability to drive, adverse effects of treatment, quality of life, progression of disease and patient preference. However, visual loss is a late event and intermediate predictors of future decline were accepted if there was good evidence that they are strong predictors of subsequent visual outcomes. These include changes detectable by investigation, but not necessarily noticed by people with AMD or STGD. ClinicalTrials.gov, the World Health Organization search portal and the UK Clinical Trials gateway were searched for ongoing and recently completed clinical trials.

RESULTS

The titles and abstracts of 7948 articles were screened for inclusion. The full text of 398 articles were obtained for further screening and checking of references and 112 articles were included in the final report. Overall, there were disappointingly few good-quality studies (including of sufficient size and duration) reporting useful outcomes, particularly in STGD. However we did identify a number of promising research topics, including drug treatments, stem cells, new forms of laser treatment, and implantable intraocular lens telescopes. In many cases, research is already under way, funded by industry or governments.

LIMITATIONS

In AMD, the main limitation came from the poor quality of much of the evidence. Many studies used VA as their main outcome despite not having sufficient duration to observe changes. The evidence on treatments for STGD is sparse. Most studies tested interventions with no comparison group, were far too short term, and the quality of some studies was poor.

FUTURE WORK

We think that the topics on which the Health Technology Assessment (HTA) and Efficacy Mechanism and Evaluation (EME) programmes might consider commissioning primary research are in STGD, a HTA trial of fenretinide (ReVision Therapeutics, San Diego, CA, USA), a visual cycle inhibitor, and EME research into the value of lutein and zeaxanthin supplements, using short-term measures of retinal function. In AMD, we suggest trials of fenretinide and of a potent statin. There is epidemiological evidence from the USA that the drug, levodopa, used for treating Parkinson's disease, may reduce the incidence of AMD. We suggest that similar research should be carried out using the large general practice databases in the UK. Ideally, future research should be at earlier stages in both diseases, before vision is impaired, using sensitive measures of macular function. This may require early detection of AMD by screening.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016038708.

FUNDING

The National Institute for Health Research HTA programme.