The relationship of atherosclerosis to the 10-year cumulative incidence of age-related macular degeneration: the Beaver Dam studies

Anti-VEGF Drugs in Age-Related Macular Degeneration: A Focus on Dosing Regimen-Related Safety and Efficacy

Age-related macular degeneration (AMD) is one of the main causes of visual impairment and severe visual loss, and can progress to two advanced forms-neovascularization and atrophic. The field of anti-AMD drugs has undergone huge developments in recent years, from single-target intravitreal administration to current clinical studies with multi-target and non-invasive agents, offering interesting new pharmacological opportunities for the treatment of this disease. Hence, we summarize some of the approved anti-vascular endothelial growth factor (VEGF) drugs for neovascular AMD, especially their structural characteristics, clinical manifestations, dosing regimens, and safety issues of the anti-VEGF drugs highlighted. In addition, advances in atrophic AMD drug research are also briefly described.

Hypertension affects the treatment of wet age-related macular degeneration

Purpose

Due to population ageing as well as the high prevalence of hypertension and age‐related macular degeneration (AMD) in elderly individuals, and the relationship between hypertension and AMD is unclear. Our research aimed to investigate the association between hypertension, wet AMD (wAMD) and the treatment strategy of wAMD patients affected by hypertension.

Methods

Data of wAMD patients at Zhongshan Ophthalmic Center, Sun Yat‐sen University, between 1 January 2002 and 30 June 2019, were extracted from the electronic healthcare information system. wAMD patients were divided into subgroups by hypertension status, age, sex, the need for vitrectomy surgery and the number of anti‐VEGF drug intravitreal injections that these were divided in 1–3 vs. >3 (available time from 1 January 2012 to 30 June 2019).

Results

A total of 3096 wAMD patients (41.7% female, 58.3% male) with an age range of 50–96 years (68.7 (SD 9.42) years) were included. wAMD was significantly associated with hypertension (p < 0.001). After adjustment for sex and age, Cox regression model showed a significant association between hypertension in wAMD patients and the number of injections (RR = 1.31, 95% CI: 1.13–1.50, p < 0.001). There was no significant association between hypertension and the need for vitrectomy (p = 0.82).

Conclusions

wet AMD was associated with hypertension status, and after the regular series of three injections, wAMD patients with hypertension were more likely to receive anti‐VEGF drug intravitreal injections than those without hypertension. These results may facilitate prospective research on the prevention of wAMD and contribute to the management of wAMD patients.

Inhibition of APE1/Ref-1 for Neovascular Eye Diseases: From Biology to Therapy

Proliferative diabetic retinopathy (PDR), neovascular age-related macular degeneration (nvAMD), retinopathy of prematurity (ROP) and other eye diseases are characterized by retinal and/or choroidal neovascularization, ultimately causing vision loss in millions of people worldwide. nvAMD and PDR are associated with aging and the number of those affected is expected to increase as the global median age and life expectancy continue to rise. With this increase in prevalence, the development of novel, orally bioavailable therapies for neovascular eye diseases that target multiple pathways is critical, since current anti-vascular endothelial growth factor (VEGF) treatments, delivered by intravitreal injection, are accompanied with tachyphylaxis, a high treatment burden and risk of complications. One potential target is apurinic/apyrimidinic endonuclease 1/reduction-oxidation factor 1 (APE1/Ref-1). The multifunctional protein APE1/Ref-1 may be targeted via inhibitors of its redox-regulating transcription factor activation activity to modulate angiogenesis, inflammation, oxidative stress response and cell cycle in neovascular eye disease; these inhibitors also have neuroprotective effects in other tissues. An APE1/Ref-1 small molecule inhibitor is already in clinical trials for cancer, PDR and diabetic macular edema. Efforts to develop further inhibitors are underway. APE1/Ref-1 is a novel candidate for therapeutically targeting neovascular eye diseases and alleviating the burden associated with anti-VEGF intravitreal injections.

Retinal Vessel Functionality Is Linked With ARMS2 A69S and CFH Y402H Polymorphisms and Choroidal Status in AMD Patients

Purpose

We aimed to investigate the reactivity of retinal vessels to a flickering stimulus in patients with age-related macular degeneration (AMD) and healthy participants. We also assessed whether the parameters of retinal vessels are dependent on genetic predisposition.

Methods

A total of 354 patients with AMD and 121 controls were recruited for the study. All participants underwent thorough ophthalmologic examination and static and dynamic retinal vessel analysis. AMD risk polymorphisms were genotyped in the CFH and ARMS2 genes.

Results

We found no differences between the AMD group and controls in central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE), arteriovenous ratio (AVR), dynamic analysis of arteries (DAAs), or dynamic analysis of veins (DAVs). Eyes with early AMD presented with significantly higher AVR values than eyes with late AMD. In the AMD group, DAA correlated positively with both choroidal thickness (Rs = 0.14, P = 0.00096) and choroidal volume (Rs = 0.23, P < 0.0001), and no such associations were observed in the controls. We found significantly lower DAA (1.47 ± 1.50) in TT homozygotes for the ARMS2 A69S polymorphism in comparison with GG homozygotes (2.38 ± 1.79) and patients with GG + GT genotypes (2.28 ± 1.84). We also observed less prominent DAV (3.24 ± 1.71) in patients with TC + CC genotypes in the CFH Y402H polymorphism compared with TT homozygotes (3.83 ± 1.68).

Conclusions

Our findings suggest that retinal microcirculation appears to be associated with the genetic background, choroidal parameters, and clinical features of the patients with AMD.

Thyroid disease is associated with higher age-related macular degeneration risk: results from a meta-analysis of epidemiologic studies

BACKGROUND

Although epidemiologic studies have suggested that thyroid disease may be a risk factor for age-related macular degeneration (AMD), this finding is still controversial.

OBJECTIVES

The aim of this meta-analysis was to investigate whether an association exists between thyroid disease and medication and AMD in epidemiologic studies.

METHODS

We searched PubMed, EMBASE, and Google Scholar from their inception to March 2020 for cross-sectional, case-control and cohort studies that assessed thyroid function and AMD risk. Data from selected studies were extracted, and a meta-analysis was performed using fixed-effect or random-effect models. The statistical heterogeneity (I2) among studies and the possibility of publication bias were evaluated. If I2 > 50%, a significant heterogeneity existed among studies and a random effects model was used to calculate the pooled RR. Otherwise, a fixed-effects model was performed.

RESULTS

A total of 13 epidemiologic studies that consisted of 7 thyroid disease and 7 thyroid medication studies were included. Statistically significant heterogeneity was observed in the study results (I2 thyroid disease = 80.1%, I2 thyroid medication = 69.0%). A significant positive association was found between thyroid disease and AMD, with an overall relative risk (RR) of 1.25 (95% CI: 1.02, 1.54). However, there was no statistical association between thyroid medication and AMD risk (pooled RR 1.26 [95% CI 0.92-1.72]). Egger's test indicated that there was no significant publication bias for thyroid disease (P=0.889) or thyroid medication (P = 0.226).

CONCLUSIONS

Our findings indicate that thyroid disease is associated with higher AMD risk. Thyroid disease prevention strategies may have a significant effect on the prevention of AMD and warrant further evaluation.

The Relationship between Age-Related Macular Degeneration and Cardiovascular Disease: A Meta-Analysis

Background:

Age-related macular degeneration (AMD) and cardiovascular disease (CVD) share pathogenic mechanisms, and their lead-lag relationship remains unclear. We performed a meta-analysis of data from longitudinal studies to evaluate the interactive association between age-related macular degeneration (AMD) and cardiovascular disease (CVD).

Methods:

A literature search was performed in PubMed, Embase, and Cochrane Library up to Feb 2019. Estimates were pooled by study quality and type of AMD and CVD. Publication bias was assessed by Begg’s test.

Results:

We identified nine studies for the risk of AMD in CVD and ten studies for the risk of CVD in AMD. Overall, evidence for the risk of CVD in AMD patients was most robust. Both early and late AMD preceded CVD, but more solid significance existed in late AMD. Among the types of CVD, stroke was more tightly associated with AMD than coronary heart disease. Publication bias was not significant in either direction.

Conclusion:

AMD is a risk factor for CVD, which is primarily driven by the increased risk of stroke in patients with late AMD. Moreover, these results suggested that AMD treatment and screening for CVD in AMD patients may have unexplored clinical benefits.

The posterior eye with age-related macular degeneration has isotropic and nonlinear viscoelastic properties

Here we characterize and compare the anisotropic and nonlinear viscoelastic properties of the posterior eye of advanced dry age-related macular degeneration (AMD) patients and age-matched normal subjects. Ten normal horizontal, ten normal vertical, ten AMD horizontal, and ten AMD vertical strips of the macular retina and the underlying choroid and sclera were preloaded, preconditioned, and subjected to incremental stress-relaxation tests in body-temperature saline. The stress-relaxation response was characterized by a fully nonlinear viscoelastic formulation in which the relaxation modulus was approximated by a Prony series and a second-order polynomial using the comprehensive viscoelastic characterization method. Normal retina, choroid, and sclera were found to be anisotropic, whereas AMD tissues were isotropic. AMD retina and choroid showed greater stress-relaxation response than normal tissues (p < 0.05), whereas AMD sclera had smaller stress-relaxation response than normal tissue (p < 0.05). The nonlinear viscoelastic stress-strain relationship of the posterior eye is hence describable for the first time.

REvisiting Lipids in REtinal Diseases: A Focused Review on Age-related Macular Degeneration and Diabetic Retinopathy

Dyslipidemia refers to an abnormal amount of lipid in the blood, and the total cholesterol level is defined as the sum of high-density lipoprotein cholesterol, low-density lipoprotein (LDL) cholesterol, and very-LDL cholesterol concentrations. In Korea, the westernization of lifestyle habits in recent years has caused an increase in the incidence of dyslipidemia, which is an important risk factor of cardiovascular disease (CVD). Several studies have been conducted on how dyslipidemia affects not only CVD, but also chorioretinal diseases such as age-related macular degeneration (AMD) and diabetic retinopathy. Recently, a pathological model of AMD was proposed under the assumption that AMD proceeds through a mechanism similar to that of atherosclerotic CVD. However, controversy remains regarding the relationship between chorioretinal diseases and lipid levels in the blood, and the effects of lipid-lowering agents. Herein, we summarize the role of lipids in chorioretinal diseases. In addition, the effects of lipid-lowering agents on the prevention and progression of chorioretinal diseases are presented.

Is dietary fat associated with the risk of age-related macular degeneration? Protocol for a systematic review and meta-analysis

Previous studies evaluating the association of dietary fat and risk of age-related macular degeneration (AMD) yield discrepant results. The objective of this systematic review (SR) and meta-analysis is to establish whether an association exists between dietary fat and AMD. This protocol was developed in line with the quality requirements of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) statement. PubMed and EMBASE will be searched for randomized controlled trials (RCTs), non-randomized trials (NRTs), cross-sectional studies, cohort studies, and case-control studies that evaluate the total incidence of AMD. The data extraction content and quantitative analysis will be carried out systematically. Newcastle-Ottawa Scale (NOS), the Cochrane risk of bias tool, and quality assessment tools will be used for quality assessment. This SR will synthesize evidence to determine if there is an association between dietary fat and AMD. The evidence would provide rationale for future research and serve as a basis for the development of future guidelines. Results are expected to be publicly available in mid 2020.PROSPERO registration number: CRD42019137086.

Choroidal Neovascularization: Mechanisms of Endothelial Dysfunction

Many conditions affecting the heart, brain, and even the eyes have their origins in blood vessel pathology, underscoring the role of vascular regulation. In age-related macular degeneration (AMD), there is excessive growth of abnormal blood vessels in the eye (choroidal neovascularization), eventually leading to vision loss due to detachment of retinal pigmented epithelium. As the advanced stage of this disease involves loss of retinal pigmented epithelium, much less attention has been given to early vascular events such as endothelial dysfunction. Although current gold standard therapy using inhibitors of vascular endothelial growth factor (VEGF) have achieved initial successes, some drawbacks include the lack of long-term restoration of visual acuity, as well as a subset of the patients being refractory to existing treatment, alluding us and others to hypothesize upon VEGF-independent mechanisms. Against this backdrop, we present here a nonexhaustive review on the vascular underpinnings of AMD, implications with genetic and systemic factors, experimental models for studying choroidal neovascularization, and interestingly, on both endothelial-centric pathways and noncell autonomous mechanisms. We hope to shed light on future research directions in improving vascular function in ocular disorders.

The relationships between the pulsatile flow form of ocular microcirculation by laser speckle flowgraphy and the left ventricular end-diastolic pressure and mass

To evaluate the relationships between parameters of the pulsatile flow form in the optic nerve head shown by laser speckle flowgraphy (LSFG) and the left ventricular (LV) end-diastolic pressure and mass obtained by echocardiography. We cross sectional analyzed the cases of 175 subjects who had undergone polysomnography. Standard M-mode two-dimensional color Doppler imaging was performed to evaluate the E/e' ratio (which represents the LV end-diastolic pressure) and LV mass. The pulsatile flow form analysis parameters of the blowout score and acceleration time index were evaluated. The parameters were analyzed separately for the tissue, vessels and throughout the optic nerve head (All). We performed a single regression analysis and a multiple regression analysis to determine whether pulsatile flow form are independent factors for the E/e' ratio and LV mass. The factors contributing independently to the E/e' ratio were blowout time-Tissue (standard regression = - 0.27, t-value = - 2.90, p < 0.0001) and body mass index (BMI) (0.16, 2.05, p = 0.04). The factors that were shown to independently contribute to the LV mass were urinary albumin concentration (0.30, - 2.90, p < 0.0001), BMI (0.28, 4.09, p < 0.0001), differences of gender (men = 1, women = 0: 0.23, 3.28, p = 0.001), acceleration time index-Vessel (- 0.23, - 2.99, p = 0.003) and mean arterial blood pressure (0.17, 2.61, p = 0.01). Our results confirmed that parameters of the pulsatile flow form of ocular microcirculation obtained by LSFG are significantly correlated with the LV end-diastolic pressure ratio and LV mass.

Models of retinal diseases and their applicability in drug discovery

INTRODUCTION

The impact of vision debilitating diseases is a global public health concern, which will continue until effective preventative and management protocols are developed. Two retinal diseases responsible for the majority of vision loss in the working age adults and elderly populations are diabetic retinopathy (DR) and age-related macular degeneration (AMD), respectively. Model systems, which recapitulate aspects of human pathology, are valid experimental modalities that have contributed to the identification of signaling pathways involved in disease development and consequently potential therapies. Areas covered: The pathology of DR and AMD, which serve as the basis for designing appropriate models of disease, is discussed. The authors also review in vitro and in vivo models of DR and AMD and evaluate the utility of these models in exploratory and pre-clinical studies. Expert opinion: The complex nature of non-Mendelian diseases such as DR and AMD has made identification of effective therapeutic treatments challenging. However, the authors believe that while in vivo models are often criticized for not being a 'perfect' recapitulation of disease, they have been valuable experimentally when used with consideration of the strengths and limitations of the experimental model selected and have a place in the drug discovery process.

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.

Sensory Impairments and Risk of Mortality in Older Adults

Background

Sensory impairments increase with age and the majority of older people will experience a sensory impairment if they live long enough. However, the relationships of hearing, visual, and olfactory impairments with mortality are not well understood.

Methods

Epidemiology of Hearing Loss Study participants (n = 2,418) aged 53-97 years (mean = 69 years) were examined in 1998-2000 and hearing, visual acuity, and olfaction were measured. Participants were followed for mortality for up to 17 years (mean = 12.8 years). Cox proportional hazards models were used to assess the association between prevalent sensory impairments and the 15-year cumulative incidence of death.

Results

A total of 1,099 (45.4%) of participants died during the follow-up period. In age- and sex-adjusted Cox models, the risk of mortality was higher among participants with one (hazard ratio [HR] = 1.40, 95% confidence interval [CI] = 1.19, 1.64) or two or more (HR = 2.12, 95% CI = 1.74, 2.58) sensory impairments than among participants with no sensory impairments. Olfactory impairment at baseline was significantly associated with mortality (HR = 1.28, 95% CI = 1.07, 1.52) after adjusting for age, sex, sensory comorbidities, cardiovascular risk factors and disease, cognitive impairment, frailty, subclinical atherosclerosis, and inflammatory marker levels (n = 1,745). Hearing and visual impairment were not associated with mortality after adjusting for subclinical atherosclerosis and inflammation.

Conclusion

Olfactory impairment, but not hearing or visual impairment, was associated with an increased risk of mortality. These results suggest that olfactory impairment may be a marker of underlying physiologic processes or pathology that is associated with aging and reduced survival in older adults.

Arterial stiffness shown by the cardio-ankle vascular index is an important contributor to optic nerve head microcirculation

PROPOSE

The purpose of this study was to determine whether there were significant correlations between the pulse waveform in the capillary area of the optic nerve head (ONH) microcirculation shown by laser speckle flowgraphy (LSFG) and parameters of the systemic condition, especially the cardio-ankle vascular index (CAVI).

METHOD

We studied 130 men (ages 60.5 ± 10.9 years) who visited the Vascular Function Section of the Department of Cardiovascular Center of Toho University Sakura Medical Center. We evaluated the skew and blowout time (BOT) - which are parameters of pulse waveform analyses - using LSFG in the capillary area of the ONH for each patient. The CAVI, the E/e' ratio as the measure of diastolic left ventricular function, and the mean intima-media thickness (IMT) were evaluated as systemic parameters. We performed a Pearson's correlation analysis and a multiple regression analysis to determine independent factors for skew and BOT.

RESULTS

Heart rate, spherical refraction, and the CAVI (standard regression = 0.18, t = 2.61, p = 0.01) were revealed as factors contributing independently to the skew by multiple regression analysis. Heart rate, the CAVI (standard regression = -0.27, t = -3.92, p = 0.0002), the urinary albumin concentration, the mean IMT, spherical refraction, body mass index and pulse pressure were revealed as factors contributing independently to the BOT by multiple regression analysis.

CONCLUSION

The CAVI was demonstrated to be an independent factor contributing to both skew and BOT in the capillary area of the ONH. Our findings clarified that large arterial function shown by the CAVI contributes to smooth hemodynamics of microcirculation, shown by LSFG.

Rethinking Nuclear Receptors as Potential Therapeutic Targets for Retinal Diseases

Collectively, retinal diseases, including age-related macular degeneration, retinitis pigmentosa, and diabetic retinopathy, result in severe vision impairment worldwide. The absence and/or limited availability of successful drug therapies for these blinding disorders necessitates further understanding their pathobiology and identifying new targetable signaling pathways. Nuclear receptors are transcription regulators of many key aspects of human physiology, as well as pathophysiology, with reported roles in development, aging, and disease. Some of the pathways regulated by nuclear receptors include, but are not limited to, angiogenesis, inflammation, and lipid metabolic dysregulation, mechanisms also important in the initiation and development of several retinal diseases. Herein, we present an overview of the biology of three diseases affecting the posterior eye, summarize a growing body of evidence that suggests direct or indirect involvement of nuclear receptors in disease progression, and discuss the therapeutic potential of targeting nuclear receptors for treatment.

Effects of adiponectin polymorphisms on the risk of advanced age-related macular degeneration

OBJECTIVE

To determine the relationships between variants in adiponectin gene (ADIPOQ) with advanced forms of age-related macular degeneration (AMD) susceptibility.

METHODS

A total of 189 advanced AMD patients and 168 controls were recruited. Seven tagging single-nucleotide polymorphisms in ADIPOQ were genotyped by the SNaPshot method.

RESULTS

Alleles or genotypes of rs822396 distributed significantly differently in advanced AMD patients and controls. The minor allele G at rs822396 was associated with an increased risk of advanced AMD in a dominant model. Furthermore, haplotype analysis revealed that haplotypes AGGACCT and TGACCCC were significantly increased the advanced AMD susceptibility, whereas haplotypes AGAACGC, TGAACGT and TGACAGC had protective effects.

CONCLUSION

ADIPOQ genetic variant rs822396 might affect an individual's susceptibility to AMD, making it efficient genetic biomarkers for early detection of AMD.

Inflammation and its role in age-related macular degeneration

Inflammation is a cellular response to factors that challenge the homeostasis of cells and tissues. Cell-associated and soluble pattern-recognition receptors, e.g. Toll-like receptors, inflammasome receptors, and complement components initiate complex cellular cascades by recognizing or sensing different pathogen and damage-associated molecular patterns, respectively. Cytokines and chemokines represent alarm messages for leukocytes and once activated, these cells travel long distances to targeted inflamed tissues. Although it is a crucial survival mechanism, prolonged inflammation is detrimental and participates in numerous chronic age-related diseases. This article will review the onset of inflammation and link its functions to the pathogenesis of age-related macular degeneration (AMD), which is the leading cause of severe vision loss in aged individuals in the developed countries. In this progressive disease, degeneration of the retinal pigment epithelium (RPE) results in the death of photoreceptors, leading to a loss of central vision. The RPE is prone to oxidative stress, a factor that together with deteriorating functionality, e.g. decreased intracellular recycling and degradation due to attenuated heterophagy/autophagy, induces inflammation. In the early phases, accumulation of intracellular lipofuscin in the RPE and extracellular drusen between RPE cells and Bruch's membrane can be clinically detected. Subsequently, in dry (atrophic) AMD there is geographic atrophy with discrete areas of RPE loss whereas in the wet (exudative) form there is neovascularization penetrating from the choroid to retinal layers. Elevations in levels of local and systemic biomarkers indicate that chronic inflammation is involved in the pathogenesis of both disease forms.

Thyroid function and age-related macular degeneration: a prospective population-based cohort study--the Rotterdam Study

BACKGROUND

In animal models, lack of thyroid hormone is associated with cone photoreceptor preservation, while administration of high doses of active thyroid hormone leads to deterioration. The association between thyroid function and age-related macular degeneration (AMD) has not been investigated in the general population.

METHODS

Participants of age ≥ 55 years from the Rotterdam Study with thyroid-stimulating hormone (TSH) and/or free thyroxine (FT4) measurements and AMD assessment were included. We conducted age- and sex-adjusted Cox proportional hazards models to explore the association of TSH or FT4 with AMD, in the full range and in those with TSH (0.4-4.0 mIU/L) and/or FT4 in normal range (11-25 pmol/L). Cox proportional hazards models were performed for the association of TSH or FT4 with retinal pigment alterations (RPA), as an early marker of retinal changes. Multivariable models additionally included cardiovascular risk factors and thyroid peroxidase antibodies positivity. We also performed stratification by age and sex. A bidirectional look-up in genome-wide association study (GWAS) data for thyroid parameters and AMD was performed. Single nucleotide polymorphisms (SNPs) that are significantly associated with both phenotypes were identified.

RESULTS

We included 5,573 participants with a median follow-up of 6.9 years (interquartile range 4.4-10.8 years). During follow-up 805 people developed AMD. TSH levels were not associated with increased risk of AMD. Within normal range of FT4, participants in the highest FT4 quintile had a 1.34-fold increased risk of developing AMD, compared to individuals in the middle group (95% confidence interval [CI] 1.07-1.66). Higher FT4 values in the full range were associated with a higher risk of AMD (hazard ratio 1.04, CI, 1.01-1.06 per 1 pmol/L increase). Higher FT4 levels were similarly associated with a higher risk of RPA. Restricting analyses to euthyroid individuals, additional multivariable models, and stratification did not change estimates. We found a SNP (rs943080) in the VEGF-A gene, associated with AMD, to be significant in the TSH GWAS (P = 1.2 x 10(-4)). Adding this SNP to multivariable models did not change estimates.

CONCLUSIONS

Higher FT4 values are associated with increased risk of AMD - even in euthyroid individuals - and increased risk of RPA. Our data suggest an important role of thyroid hormone in pathways leading to AMD.

Systemic levels of vascular endothelial growth factor before and after intravitreal injection of aflibercept or ranibizumab in patients with age-related macular degeneration: a randomised, prospective trial

PURPOSE

To evaluate the changes of vascular endothelial growth factor (VEGF) plasma levels after intravitreal injections of aflibercept or ranibizumab in patients with exudative age-related macular degeneration (AMD).

METHODS

Thirty-eight patients with exudative AMD were included in this randomised, prospective study. Nineteen patients were randomised to treatment with intravitreal aflibercept (2.0 mg) and 19 to intravitreal ranibizumab (0.5 mg). The concentration of VEGF was measured by ELISA just before the injection, after 7 days and 1 month. Twenty-two age- and sex-matched healthy patients without chorioretinal diseases served as control.

RESULTS

The median baseline plasma VEGF concentration was 61.0 pg/ml in the control group, 43.0 pg/ml in the aflibercept group and 59.0 pg/ml in the ranibizumab group (p=0.127). Seven days after intravitreal injection of aflibercept plasma levels were significantly reduced to values below the minimum detectable dose (MDD) in 17 of 19 patients (89.5%) resulting in a median VEGF concentration of <9 pg/ml (p<0.001). The reduction persisted throughout 1 month with values below the MDD in 5 of 19 patients (26.3%) and a median measurement of 17.0 pg/ml (p<0.001). In patients treated with ranibizumab no significant effects could be observed with a baseline VEGF of 59.0 pg/ml, 54.0 pg/ml at 7 days (p=0.776) and 58.5 pg/ml at 4 weeks of follow-up (p=0.670).

CONCLUSION

After intravitreal aflibercept injection, the systemic VEGF levels were significantly reduced throughout the observational period of 4 weeks. No significant systemic effects of intravitreal ranibizumab on plasma VEGF were observed.

Age-Related Macular Degeneration: Advances in Management and Diagnosis

Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in older populations in industrialized nations. AMD is a late-onset deterioration of photoreceptors and retinal pigment epithelium in the central retina caused by various environmental and genetic factors. Great strides in our understanding of AMD pathogenesis have been made in the past several decades, which have translated into revolutionary therapeutic agents in recent years. In this review, we describe the clinical and pathologic features of AMD and present an overview of current diagnosis and treatment strategies.

Aspirin use and early age-related macular degeneration: a meta-analysis

OBJECTIVE

The aim of this review was to evaluate the evidence for an association between Aspirin use and early age-related macular degeneration (ARMD).

METHODS

A literature search was performed in 5 databases with no restrictions on language or date of publication. Four studies involving 10292 individuals examining the association between aspirin and ARMD met the inclusion criteria. Meta-analysis was carried out by Cochrane Collaboration Review Manager 5.2 software (Cochrane Collaboration, Copenhagen, Denmark).

RESULTS

The pooled odd ratios showed that Aspirin use was associated with early ARMD (pooled odds ratio 1.43, 95% CI 1.09-1.88).

CONCLUSIONS

There is a small but statistically significant association between Aspirin use and early ARMD, which may warrant further investigation.

Clinical characteristics and current treatment of age-related macular degeneration

Age-related macular degeneration (AMD) is a multifactorial degeneration of photoreceptors and retinal pigment epithelium. The societal impact is significant, with more than 2 million individuals in the United States alone affected by advanced stages of AMD. Recent progress in our understanding of this complex disease and parallel developments in therapeutics and imaging have translated into new management paradigms in recent years. However, there are many unanswered questions, and diagnostic and prognostic precision and treatment outcomes can still be improved. In this article, we discuss the clinical features of AMD, provide correlations with modern imaging and histopathology, and present an overview of treatment strategies.

Age-related macular degeneration: linking clinical presentation to pathology

Age-related macular degeneration (AMD) is one of the leading causes of blindness worldwide in the elderly population. Optometrists, as primary eye health care providers, require the skills and knowledge to accurately diagnose and manage AMD patients. There is an overwhelming body of research related to the clinical presentation, etiology, epidemiology, and pathology of this disease. Additionally, the evolution of new imaging modalities creates new opportunities to clinically detect and analyze previously uncharacterized and earlier changes in the retina. The challenge for optometrists is to combine all this information into an applicable knowledge base for use in everyday clinical assessment of AMD so that timely and accurate referrals can be made to retinal specialists. This review attempts to address this issue by linking the clinical presentation of AMD with the underlying disease biology. We emphasize the contribution of recent noninvasive imaging technologies to the clinical assessment of early and more advanced AMD including optical coherence tomography, fundus autofluorescence, and infrared reflectance.

Lipids, lipid genes, and incident age-related macular degeneration: the three continent age-related macular degeneration consortium

PURPOSE

To describe associations of serum lipid levels and lipid pathway genes to the incidence of age-related macular degeneration (AMD).

DESIGN

Meta-analysis.

METHODS

setting: Three population-based cohorts. population: A total of 6950 participants from the Beaver Dam Eye Study (BDES), Blue Mountains Eye Study (BMES), and Rotterdam Study (RS). observation procedures: Participants were followed over 20 years and examined at 5-year intervals. Hazard ratios associated with lipid levels per standard deviation above the mean or associated with each additional risk allele for each lipid pathway gene were calculated using random-effects inverse-weighted meta-analysis models, adjusting for known AMD risk factors. main outcome measures: Incidence of AMD.

RESULTS

The average 5-year incidences of early AMD were 8.1%, 15.1%, and 13.0% in the BDES, BMES, and RS, respectively. Substantial heterogeneity in the effect of cholesterol and lipid pathway genes on the incidence and progression of AMD was evident when the data from the 3 studies were combined in meta-analysis. After correction for multiple comparisons, we did not find a statistically significant association between any of the cholesterol measures, statin use, or serum lipid genes and any of the AMD outcomes in the meta-analysis.

CONCLUSION

In a meta-analysis, there were no associations of cholesterol measures, history of statin use, or lipid pathway genes to the incidence and progression of AMD. These findings add to inconsistencies in earlier reports from our studies and others showing weak associations, no associations, or inverse associations of high-density lipoprotein cholesterol and total cholesterol with AMD.

Emerging roles for nuclear receptors in the pathogenesis of age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly in the Western world. Over the last 30 years, our understanding of the pathogenesis of the disease has grown exponentially thanks to the results of countless epidemiology, genetic, histological, and biochemical studies. This information, in turn, has led to the identification of multiple biologic pathways potentially involved in development and progression of AMD, including but not limited to inflammation, lipid and extracellular matrix dysregulation, and angiogenesis. Nuclear receptors are a superfamily of transcription factors that have been shown to regulate many of the pathogenic pathways linked with AMD and as such they are emerging as promising targets for therapeutic intervention. In this review, we will present the fundamental phenotypic features of AMD and discuss our current understanding of the pathobiological disease mechanisms. We will introduce the nuclear receptor superfamily and discuss the current literature on their effects on AMD-related pathophysiology.

Is age-related macular degeneration a manifestation of systemic disease? New prospects for early intervention and treatment

Age-related macular degeneration (AMD) is a common vision-threatening condition affecting the elderly. AMD shares common risk factors and processes, including vascular and inflammatory pathways, with many systemic disorders. Associations have been reported between AMD and hypertension, cardiovascular disease, cerebrovascular disease, dyslipidaemia, chronic kidney disease and neurodegenerative disorders. An increasing amount of evidence suggests that individuals with AMD are also at risk of systemic diseases such as stroke. In this review, we summarize the latest evidence to support the notion that AMD is an ocular manifestation of systemic disease processes, and discuss the potential systemic side effects of ocular AMD therapy of which general physicians should be aware. Recent genetic discoveries and understanding of the pathogenic pathways in AMD in relation to systemic disorders are also highlighted.

Long-term longitudinal study of patients treated with ranibizumab for neovascular age-related macular degeneration

PURPOSE OF REVIEW

To review the current literature regarding long-term treatment beyond 2 years with anti-vascular endothelial growth factor (VEGF) inhibition for neovascular age-related macular degeneration (nv-AMD).

RECENT FINDINGS

Only few studies of anti-VEGF treatment for nv-AMD exist beyond 2 years, and the number of patients followed for 4 years or longer is small. The results of studies show that the majority of patients with nv-AMD can preserve visual acuity compared with baseline, subgroups reveal large variations in visual benefit. Approximately 20-30% of patients seem to respond poorly to the treatment, and 20% obtain a condition with inactivity and good results. The majority of patients will need continuous active treatment. Long-term decline of visual acuity reflects the natural progression of the disease, however, insufficient treatment cannot be excluded leaving a potential for further improvement. Close follow-up to detect recurrent activity of nv-AMD and activity in fellow eye is important. Definitive evidence of systemic side-effects is lacking, but long-term VEGF inhibition seems to be tolerated well with few ocular and systemic complications.

SUMMARY

The majority of patients with nv-AMD can preserve visual acuity and expect long-term treatment beyond 2 years. Ocular complications and systemic adverse events remain few.