Relationship between refraction and prevalent as well as incident age-related maculopathy: the Rotterdam Study

Association of polymorphisms in the HTRA1 gene with myopia

PURPOSE

To evaluate the associations of single-nucleotide polymorphisms (SNPs) in the high-temperature requirement protease A 1 (HTRA1) gene with myopia.

METHODS

25 SNPs in HTRA1 were selected, including 23 haplotype-tagging SNPs, SNP rs2142308 from a previous genome-wide association study (GWAS) of myopia and rs11200638, a SNP strongly associated with age-related macular degeneration (AMD). All SNPs were genotyped in a Hong Kong Chinese cohort of 533 myopia subjects (including 175 high myopia, 189 moderate myopia and 189 mild myopia) and 280 non-myopic controls. The association of individual SNPs were evaluated in overall myopia and different subgroups of myopia using logistic regression.

RESULTS

A tagging SNP, rs11200647, was significantly associated with myopia (p=2.17×10-4, OR=0.67). Nominal associations were detected for the AMD-associated SNP rs11200638 (p=0.0042, OR=1.37) and tagging SNPs rs12266322 (p=0.0048, OR=0.59) and rs17103569 (p=0.047, OR=1.34). The association of rs11200647 with myopia remained significant after adjusting for rs11200638, rs12266322 and rs17103569. In sub-group analysis, two tagging SNPs, rs11200647 (p=2.24×10-4, OR=0.58) and rs12266322 (p=8.31×10-4, OR=0.39), showed significant association with moderate myopia. In haplotype association analysis, haplotypes AT (p=1.00×10-4, OR=1.77) and haplotype GT (p=0.0019, OR=0.64), defined by rs11200647 and rs66884382, were significantly associated with myopia.

CONCLUSIONS

This study provided new evidence to support HTRA1 as an associated gene for myopia, especially moderate myopia. The findings suggested that myopia and AMD may have shared genetic components.

Association between axial length and uveitis

PURPOSE

Multiple studies have examined the association between myopia and various ocular diseases, but there is no clinical report of the relationship between myopia and uveitis. This study aimed to elucidate the relationship between myopia and uveitis by comparing axial lengths (AL) of uveitis patients with control individuals.

METHODS

This study included 1052 eyes (663 patients; 288 males, 375 females; median age 56.0 years) with uveitis referred to Tokyo Medical University Hospital. Controls were 738 eyes with cataract but no other ocular diseases. AL was measured by IOLMaster or conventional A-mode ultrasound system. Uveitis eyes were grouped into various types of non-infectious uveitis, infectious uveitis, and unidentified uveitis. Median AL of each uveitis group was compared with control group using Mann-Whitney U-test, and also compared with adjustment for age and sex using multiple regression analysis. Binary logistic analysis was performed to examine whether AL plays a role in the risk of developing uveitis.

RESULTS

Of 1052 eyes, 808 eyes (76.8%) were diagnosed with non-infectious uveitis [sarcoidosis (176 eyes, 16.7%), Vogt-Koyanagi-Harada disease (122 eyes, 11.6%), Behçet's disease (130 eyes, 12.4%), and others (380 eyes, 36.1%)], 146 eyes (13.9%) with infectious uveitis, and 98 eyes (9.3%) with unidentified uveitis. Median AL in all uveitis eyes was significantly shorter than in control eyes (23.73 vs 24.31 mm, p < 0.001 unadjusted), and AL remained significantly shorter in uveitis than in control after age- and sex-adjustment (p < 0.001). Median AL was significantly shorter in non-infectious uveitis (23.72 mm) and in infectious uveitis (23.99 mm) compared to controls (p < 0.001 and < 0.05, respectively), and was significantly shorter in non-infectious uveitis than in infectious uveitis (p < 0.05). Each millimeter decrease in AL was associated with 1.266-fold increase in unadjusted risk [odds ratio (OR), 1.266; 95% confidence interval (CI), 1.196-1.341; p < 0.001) and 1.446-fold in age- and sex-adjusted risk (OR, 1.446; 95% CI, 1.349-1.549; p < 0.001) of developing uveitis.

CONCLUSION

Median AL of uveitis eyes with infectious or non-infectious etiologies was significantly shorter than that in control eyes, suggesting an increased risk of developing uveitis in eyes with shorter AL. This feature should be considered when exploring new pathogenetic mechanisms of uveitis.

KEY MESSAGES

What is known Shorter axial length may be associated with the pathogenesis of central serous chorioretinopathy and increased risk of early age-related macular degeneration. What is new Here we assessed the relationship between myopia and uveitis by comparing axial lengths of uveitis patients. Median axial length in all uveitis eyes was significantly shorter than in control eyes, and axial length remained significantly shorter in uveitis than in control after age- and sex-adjustment. Each millimeter decrease in axial length was associated with 1.266-fold increase in unadjusted risk and 1.446-fold in age- and sex-adjusted risk of developing uveitis.

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.

Clinical and anatomical features of myopia

The purpose of the review is to summarize clinical and anatomically-related aspects of myopia. Recent studies have revealed macular atrophy as myopic maculopathy (MMP) stage-4 was accompanied by a central Bruch´s membrane (BM) defect associated with a subretinal proliferation (as sign of previous macular neovascularization). Patchy atrophies (MMP-stage 3) could be differentiated into those without versus with BM defects/subretinal proliferations. BM defects and subretinal proliferations were associated with each other (OR: 78.3; P < 0.001). Fundus tessellation as MMP-stage-1 correlated with visual acuity reduction, suggesting pathological changes already at MMP stage 1, in addition to a leptochoroid as risk factor. Myopic parapapillary beta zone (potentially caused by an axial elongation-related enlargement of the retinal pigment epithelium [RPE] layer opening; characterized by small or no alpha zone, few or no RPE drusen at its border, normal BM thickness) can be differentiated from glaucomatous parapapillary beta zone (characterized by alpha zone, RPE drusen, and thickened BM). The overlying retinal layers extended into the parapapillary zones, deeper than the superficial layers. Prevalence of non-glaucomatous optic neuropathy increased non-linearly with longer axial length in highly myopic eyes and was a major cause for vision loss in high myopia. In patients aged 85 + years, prevalence of MMP stage 3 or 4 in highly myopic eyes (axial length ≥ 26.5 mm) was about 75 %. Myopia was associated with a lower prevalence of diabetic retinopathy, age-related macular degeneration and angle-closure glaucoma, while high myopia, more than moderate myopia, was associated with higher prevalence and incidence of open-angle glaucoma.

Positive and Negative Associations of Myopia with Ocular Diseases in Population-Based Studies

PURPOSE

Prevalence of myopia and vision impairment due to myopic macular degeneration and myopia-related optic neuropathies have markedly increased worldwide. We evaluated whether myopia is associated with other ocular disorders.

DESIGN

Population-based studies conducted in Russia, China, and India.

PARTICIPANTS

The Russian Ural Eye and Medical Study (UEMS) and the Beijing Eye Study (BES) included 5899 individuals and 4439 individuals (all aged 40+ years), respectively, and the Central India Eye and Medical Study (CIEMS) consisted of 4711 individuals aged 30+ years. The studies were conducted in rural and urban regions in Bashkortostan/Russia, Nagpur/India, and Beijing/China.

METHODS

The participants underwent a series of ophthalmological and general medical examinations.

MAIN OUTCOME MEASURES

Axial length as a surrogate for myopia and prevalence of diabetic retinopathy (DR), age-related macular degeneration (AMD), angle-closure glaucoma (ACG), and open-angle glaucoma (OAG).

RESULTS

In the UEMS, DR prevalence (odds ratio [OR], 0.73), AMD prevalence (OR, 0.85), and ACG prevalence (OR, 0.72) decreased, and OAG prevalence (OR, 1.65) increased with longer axial length in multivariable analyses. In the CIEMS, lower AMD prevalence (OR, 0.81) and lower ACG prevalence (OR, 0.55), and higher OAG prevalence (OR, 1.45) were associated with longer axial length. Diabetic retinopathy prevalence (0.33%) was too low for statistical analysis in the CIEMS. In the BES, prevalence (OR, 0.64) and 10-year incidence of DR (OR, 0.48) and prevalence (OR, 0.83) and 5-year incidence of AMD (OR, 0.996) decreased, and prevalence (OR, 1.35) and 10-year incidence of OAG (OR, 1.40) increased with longer axial length. In all 3 studies, the association between higher OAG prevalence and longer axial length was nonlinear with a slight increase for the moderate myopia range and a steep increase in the highly myopic range.

CONCLUSIONS

Myopia is associated with a lower prevalence of DR, AMD, and ACG and a lower incidence of DR and AMD, whereas high myopia more than moderate myopia is associated with a higher prevalence and incidence of OAG. Future studies may assess whether in myopia (in particular, in moderate myopia), the myopia-related advantages, that is, lower prevalence of DR, AMD, and ACG, may outweigh the increased risks for OAG and other myopia-related disorders.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

UK Biobank retinal imaging grading: methodology, baseline characteristics and findings for common ocular diseases

BACKGROUND/OBJECTIVES

This study aims to describe the grading methods and baseline characteristics for UK Biobank (UKBB) participants who underwent retinal imaging in 2009-2010, and to characterise individuals with retinal features suggestive of age-related macular degeneration (AMD), glaucoma and retinopathy.

METHODS

Non-mydriatic colour fundus photographs and macular optical coherence tomography (OCT) scans were manually graded by Central Administrative Research Facility certified graders and quality assured by clinicians of the Network of Ophthalmic Reading Centres UK. Captured retinal features included those associated with AMD (≥1 drusen, pigmentary changes, geographic atrophy or exudative AMD; either imaging modality), glaucoma (≥0.7 cup-disc ratio, ≥0.2 cup-disc ratio difference between eyes, other abnormal disc features; photographs only) and retinopathy (characteristic features of diabetic retinopathy with or without microaneurysms; either imaging modality). Suspected cases of these conditions were characterised with reference to diagnostic records, physical and biochemical measurements.

RESULTS

Among 68,514 UKBB participants who underwent retinal imaging, the mean age was 57.3 years (standard deviation 8.2), 45.7% were men and 90.6% were of White ethnicity. A total of 64,367 participants had gradable colour fundus photographs and 68,281 had gradable OCT scans in at least one eye. Retinal features suggestive of AMD and glaucoma were identified in 15,176 and 2184 participants, of whom 125 (0.8%) and 188 (8.6%), respectively, had a recorded diagnosis. Of 264 participants identified to have retinopathy with microaneurysms, 251 (95.1%) had either diabetes or hypertension.

CONCLUSIONS

This dataset represents a valuable addition to what is currently available in UKBB, providing important insights to both ocular and systemic health.

Prevalence and determinants of reticular pseudodrusen in the Russian Ural Eye and Medical Study

PURPOSE

To assess the prevalence of reticular pseudodrusen (RPD) and their determinants.

METHODS

The Population-based Ural Eye and Medical Study conducted in Bashkortostan/Russia included 5899 participants aged 40+ years. Presence of RPDs was assessed on conventional colour fundus photographs, red-free fundus images and optical coherence tomographic images.

RESULTS

The study included 4914 (83.3%) individuals (mean age: 58.5 ± 10.5 years; range: 40-94 years). Using two age limits (>55 years and 40+ years) for the definitions of RPD and AMD (age-related macular degeneration), RPD prevalence was 186/4914 (3.8%; 95% confidence interval (CI): 3.3, 4.3) and 246/4914 (5.0%, 95% CI: 4.4, 5.6), respectively, and the prevalence of any AMD without RPD was 182/4914 (3.7%: 95% CI: 3.2, 4.2) and 224/4914 (4.6%; 95% CI: 4.0, 5.1) respectively. Within the subgroup of early AMD, intermediate AMD and late AMD, RPD prevalence (age limit: 40+ years) was 55.1% (95% CI: 49.5, 60.8), 42.9% (95% CI: 33.8, 51.9) and 33.3% (95% CI: 16.4, 50.3) respectively. In multivariable analysis, higher RPD prevalence (age limit 40+ years) was associated with higher age (odds ratio (OR): 1.08; 95% CI: 1.07, 1.10; p < 0.001), rural region of habitation (OR: 3.81; 95% CI: 2.76, 5.24; p < 0.001) and lower percentage of lymphocytes on leukocyte counts (OR: 0.95; 95% CI: 0.93, 0.97; p < 0.001). Higher prevalence of any AMD without RPD was associated with urban region (OR: 1.58; 95% CI: 1.18, 2.11; p = 0.002), lower diabetes prevalence (OR: 0.55; 95% CI: 0.33, 0.90; p = 0.02) and shorter axial length (OR: 0.85; 95% CI: 0.74, 0.98; p = 0.03), after adjusting for age.

CONCLUSIONS

Reticular pseudodrusen (mean prevalence: 3.8% (age limit >55 years); 5.0% (age limit 40+ years)) differs from AMD without RPD in its association with urban region (AMD without RPD: rural region), lower lymphocyte percentage (AMD without RPD: no association) and a lack of associations with axial length (AMD without RPD: shorter axial length) and with diabetes prevalence (AMD without RPD: lower diabetes prevalence).

Associations of refractive errors and retinal changes measured by optical coherence tomography: A systematic review and meta-analysis

Studies reporting alteration in retinal thickness using optical coherence tomography (OCT) have been performed in different populations with various degrees of refractive error, producing inconsistent results. Therefore, we performed a meta-analysis to evaluate the alterations in retinal OCT measurements in myopic and hyperopic patients compared to controls. Evaluation of different retinal layers' thickness may have significance for developing novel approaches for preventing, diagnosing, and treating refractive errors and their complications. We searched PubMed and EMBASE to identify articles that reported OCT measurements of different retinal layers and regions, including macular, foveal, parafoveal, perifoveal, foveolar, ganglion cell complex (GCC), retinal nerve fiber layer (RNFL), peripapillary retinal nerve fiber layer (pRNFL), and ganglion cell and inner plexiform layer (GC-IPL) thickness in addition to macular volume, and optic disc area in myopes and hyperopes comparing their differences with controls. We applied either a fixed-effects or random-effects model for the meta-analysis of these differences based on the assessed heterogeneity level. Furthermore, subgroup analyses and metaregression, as well as publication bias and quality assessment, were conducted for the eligible studies. Forty-seven studies with a total of 12223 eyes, including 8600 cases and 3623 non-cases, are included in this meta-analysis. Our results showed that, in comparison to controls, highly myopic eyes had a significantly lower value for mean macular thickness, macular GCC, macular GC-IPL, parafoveal, perifoveal, foveal, foveolar, RNFL, and pRNFL thickness. Compared to controls, moderately myopic eyes showed a significantly thinner mean macular GCC layer and pRNFL. On the other hand, hyperopic eyes had significantly thicker average pRNFL than controls. Several other significant differences were also observed in various regional analyses. The findings of the current study affirm the retinal OCT measurement differences between myopic and hyperopic eyes compared to controls, emphasizing OCT measurements' advantages as potential biomarkers of ocular pathologies.

Axial length and its associations in the Ural Very Old Study

To assess the distribution of axial length as surrogate for myopia and its determinants in an old population, we performed the Ural Very Old Study as a population-based cohort study. Out of 1882 eligible individuals aged 85 + years, the Ural Very Old Study performed in an urban and rural region in Bashkortostan/Russia included 1526 (81.1%) individuals undergoing ophthalmological and medical examinations with sonographic axial length measurement. Biometric data were available for 717 (47.0%) individuals with a mean age of 88.0 ± 2.6 years (range 85–98 years; 25%). Mean axial length was 23.1 ± 1.1 mm (range 19.37–28.89 mm). Prevalences of moderate myopia (axial length 24.5–< 26.5 mm) and high myopia (axial length ≥ 26.5 mm) were 47/717 (6.6%; 95% CI 4.7, 8.4) and 10/717 (1.4%; 95% CI 0.5, 2.3), respectively. In multivariable analysis, longer axial length was associated (coefficient of determination r² 0.25) with taller body height (standardized regression coefficient beta:0.16;non-standardized regression coefficient B: 0.02; 95% confidence interval (CI) 0.01, 0.03; P < 0.001), higher level of education (beta: 0.12; B: 0.07; 95% CI 0.02, 0.11; P = 0.002), and lower corneal refractive power (beta: − 0.35; B: − 0.23; 95% CI − 0.28, − 0.18; P < 0.001). Higher prevalence of moderate myopia, however not of high myopia, was associated with higher educational level (OR 1.39; 95% CI 1.09, 1.68; P = 0.007) and lower corneal refractive power (OR 0.77; 95% CI 0.63, 0.94; P = 0.01). In this old study population, prevalence of moderate axial myopia (6.6% versus 9.7%) was lower than, and prevalence of high axial myopia (1.4% versus 1.4%) was similar as, in a corresponding study on a younger population from the same Russian region. Both myopia prevalence rates were higher than in rural Central India (1.5% and 0.4%, respectively). As in other, younger, populations, axial length and moderate myopia prevalence increased with higher educational level, while high myopia prevalence was independent of the educational level.

The Risks and Benefits of Myopia Control

PURPOSE

The prevalence of myopia is increasing around the world, stimulating interest in methods to slow its progression. The primary justification for slowing myopia progression is to reduce the risk of vision loss through sight-threatening ocular pathologic features in later life. The article analyzes whether the potential benefits of slowing myopia progression by 1 diopter (D) justify the potential risks associated with treatments.

METHODS

First, the known risks associated with various methods of myopia control are summarized, with emphasis on contact lens wear. Based on available data, the risk of visual impairment and predicted years of visual impairment are estimated for a range of incidence levels. Next, the increased risk of potentially sight-threatening conditions associated with different levels of myopia are reviewed. Finally, a model of the risk of visual impairment as a function of myopia level is developed, and the years of visual impairment associated with various levels of myopia and the years of visual impairment that could be prevented with achievable levels of myopia control are estimated.

RESULTS

Assuming an incidence of microbial keratitis between 1 and 25 per 10 000 patient-years and that 15% of cases result in vision loss leads to the conclusion that between 38 and 945 patients need to be exposed to 5 years of wear to produce 5 years of vision loss. Each additional 1 D of myopia is associated with a 58%, 20%, 21%, and 30% increase in the risk of myopic maculopathy, open-angle glaucoma, posterior subcapsular cataract, and retinal detachment, respectively. The predicted mean years of visual impairment ranges from 4.42 in a person with myopia of -3 D to 9.56 in a person with myopia of -8 D, and a 1-D reduction would lower these by 0.74 and 1.21 years, respectively.

CONCLUSIONS

The potential benefits of myopia control outweigh the risks: the number needed to treat to prevent 5 years of visual impairment is between 4.1 and 6.8, whereas fewer than 1 in 38 will experience a loss of vision as a result of myopia control.

Compatibility of intravitreally applied epidermal growth factor and amphiregulin

Introduction

To examine the compatibility of intravitreally injected epidermal growth factor (EGF) and amphiregulin as EGF family member.

Methods

Four rabbits (age: 4 months; body weight: 2.5 kg) received three intravitreal injections of EGF (100 ng) uniocularly in monthly intervals and underwent ocular photography, tonometry, biometry, and optical coherence tomography. After sacrificing the rabbits, the globes were histomorphometrically examined. In a second study part, eyes of 22 guinea pigs (age: 2–3 weeks) received two intravitreal administrations of amphiregulin (10 ng) or phosphate buffered solution (PBS) in 10-day interval, or were left untouched. Ten days after the second injection, the guinea pigs were sacrificed, the enucleated eyes underwent histological and immune-histological examinations.

Results

The rabbit eyes with EGF injections versus the contralateral untouched eyes did not show significant differences in intraocular pressure (7.5 ± 2.4 mmHg vs. 6.8 ± 2.2 mmHg; P = 0.66), retinal thickness (158 ± 5 µm vs. 158 ± 3 µm; P = 1.0), cell counts in the retinal ganglion cell layer (3.3 ± 1.7 cells/150 µm vs. 3.0 ± 1.4 cells/150 µm; P = 0.83), inner nuclear layer (46.4 ± 23.2 cells/150 µm vs. 39.6 ± 6.4 cells/150 µm; P = 0.61), and outer nuclear layer (215 ± 108 cells/150 µm vs. 202 ± 47 cells/150 µm; P = 0.83), or any apoptotic retinal cells. The guinea pig eyes injected with amphiregulin versus eyes with PBS injections did not differ (P = 0.72) in the degree of microglial activation, and both groups did not differ from untouched eyes in number of apoptotic retinal cells and retinal gliosis.

Conclusions

Intravitreal applications of EGF (100 ng) in rabbits nor intravitreal applications of amphiregulin (10 ng) in guinea pigs led to intraocular specific inflammation or any observed intraocular destructive effect. The findings support the notion of a compatibility of intraocular applied EGF and amphiregulin.

Prevalence of age-related macular degeneration among optometric telemedicine users in Spain: a retrospective nationwide population-based study

PURPOSE

To evaluate the prevalence of AMD among optometric telemedicine users in Spain and to identify risk factors.

METHODS

Retrospective analysis of a nationwide database conducted on subjects attending to optometry centers, between January 2013 and December 2019. Fundus photographs were performed by optometrists, using non-mydriatic cameras, and evaluated by a group of 12 retina specialists.

RESULTS

Among the 119,877 subjects included, the overall prevalence of AMD was 7.6%. The prevalence of early, intermediate, and advanced AMD was 2.9%, 2.7%, and 2.0%, respectively. Of the 9129 AMD subjects, 1161 (12.7%) had geographic atrophy, and 1089 (11.9%) had neovascular AMD, either scar (4.5%) or exudative (7.4%). There was a significant association between AMD and age (per year older, adjusted odds ratio, OR 1.116; 95% CI 1.114 to 1.119, p<0.0001). Women had higher prevalence (adjusted OR 1.17; 95% CI 1.12 to 1.23, p<0.0001). Every diopter (spherical equivalent) of progress toward hyperopia was associated with a significant increase in early AMD prevalence (adjusted OR 1.02, 95 CI 1.01 to 1.04, p=0.0074). Presence of diabetes was associated with a lower AMD prevalence (p<0.0001).

CONCLUSIONS

The prevalence of AMD (any eye and any severity) was 7.6%, with a prevalence of advanced AMD of 2.0%. Older age and women were significantly associated with a higher prevalence of AMD, whereas myopia and presence of diabetes were associated with significantly lower odds of any AMD.

Prevalence and Associated Factors of Diabetic Retinopathy in a Russian Population. The Ural Eye and Medical Study

AIM

To assess prevalence and associated factors of diabetic retinopathy (DR) in a Russian population.

METHODS

Out of 7328 eligible individuals, the population-based cross-sectional Ural Eye and Medical Study included 5899 (80.5%) individuals aged 40+ years, who underwent a detailed medical and ophthalmological examination. Using ocular fundus photographs and optical coherence tomographic images, we assessed prevalence and degree of DR in 5105 participants.

RESULTS

DR was present in 99/5105 individuals (1.9%; 95% confidence interval [CI]: 1.6, 2.3). Its prevalence increased from 6/657 (1.0%; 95% CI: 0.2, 1.6) in the age group of 45-50 years to 24/680 (3.5%; 95% CI: 2.1, 4.9) in the age group of 65-70 years, and decreased to 3/153 (2.0%; 95% CI: 0.00, 4.2) in the age group of 80+ years. DR prevalence within the 577 (11.4%; 95% CI: 10.5, 12.2) individuals with diabetes was 99/577 (17.2%; 95% CI: 14.1, 20.2). DR was the cause for moderate-to-severe vision impairment (best corrected visual acuity <6/18 but ≥3/60) in four individuals (4/5105; 0.07%). In multivariable analysis, higher DR prevalence was associated with higher serum glucose concentration (odds ratio [OR]: 1.30; 95% CI: 1.20, 141), longer diabetes duration (OR: 1.06; 95% CI: 1.02, 1.09), type of diabetes therapy (nil/diet/oral/insulin) (OR:4.19;95% CI:3.08, 5.70), lower educational level (OR:0.81;95% CI:0.67, 0.98), lower manual dynamometric force (OR: 0.96; 95% CI: 0.94, 0.99), shorter ocular axial length (OR: 0.73; 95% CI: 0.56, 0.96), and higher diastolic blood pressure (OR: 1.04; 95% CI: 1.01, 1.06), or alternatively, higher estimated cerebrospinal fluid pressure (OR: 1.09; 95% CI: 1.01, 1.18).

CONCLUSION

In this urban and rural Russian population aged 40+ years, DR prevalence was relatively low (1.9%; 95% CI: 1.6, 2.3), showed an inverted U-shaped association with age, and in a cross-sectional study design it was associated with shorter axial length and higher estimated cerebrospinal fluid pressure.

EYES WITH SUBRETINAL DRUSENOID DEPOSITS AND NO DRUSEN: Progression of Macular Findings

PURPOSE

To investigate the macular changes over time in eyes containing subretinal drusenoid deposits (also known as pseudodrusen) with no drusen >63 µm.

METHODS

A consecutive series of patients were examined with color fundus photography, optical coherence tomography, and autofluorescence imaging with fluorescein angiography used as necessary. Exclusionary criteria included macular neovascularization, history of retinal surgery, pseudoxanthoma elasticum, and drusen >63 µm.

RESULTS

There were 85 eyes of 54 patients. The mean age at baseline was 83.6 (±7.8) years, and there were 17 men. The mean follow-up was 5.0 (±2.9) years. At initial optical coherence tomography examination, 12 eyes had extrafoveal atrophy and 17 eyes had vitelliform deposits, which were yellowish white subretinal collections that showed intense hyperautofluorescence. During follow-up, 11 eyes lost vitelliform material. After the disappearance of small deposits, focal hyperpigmentation remained. Loss of larger deposits was associated with noteworthy sequela; six developed subfoveal atrophy and one macular neovascularization close to regressing vitelliform material. Subfoveal geographic atrophy developed in four other eyes without vitelliform material by extension from areas of extrafoveal atrophy. Macular neovascularization developed in seven eyes over follow-up. The CFH Y402H and ARMS2 A69S allele frequencies were 57% and 48.9%, respectively, which is similar to a group of age-related macular degeneration controls. One patient had a novel PRPH2 mutation, but did not have a vitelliform deposit; the remainder had a normal PRPH2 and BEST1 coding sequences.

CONCLUSION

Eyes with subretinal drusenoid deposits and no drusen >63 mm have significant risk for the development of both neovascularization and geographic atrophy, the fundamental components of late age-related macular degeneration. An intermediate step in some eyes was the development of a vitelliform deposit, an entity not traditionally associated with age-related macular degeneration, but in these patients, the material seemed to be an important component of the disease pathophysiology. This vitelliform deposit was not associated with genetic markers for pattern dystrophy or Best disease.

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.

Age- and sex-based evaluation of the association between refractive error and age-related macular degeneration in the Korean population

PURPOSE

The aim of this study was to investigate the association between refractive error and prevalence of age-related macular degeneration (AMD) in Korean adults, based on the sex and age group.

METHODS

This was a nationwide population-based cross-sectional study that included 17,676 subjects aged over 40 years who participated in the 2008-2012 Korean National Health and Nutrition Examination Survey. Digital fundus images (45°) were obtained for both eyes under physiologic mydriasis and were graded using the international classification and grading system for age-related macular degeneration. The spherical equivalents of refractive errors were calculated in diopters using auto-refraction data.

RESULTS

After adjustment for potential confounders, myopia was associated with lower risk of any age-related macular degeneration [odds ratio (OR), 0.74; 95% Confidence Interval (CI), 0.61-0.91]. In particular, myopia was significantly associated with lower odds of age-related macular degeneration in female participants (any AMD: OR, 0.71; 95% CI, 0.54-0.93; early AMD: OR, 0.70; 95% CI, 0.53-0.93) and in participants younger than 50 years (any AMD: OR, 0.46; 95% CI, 0.24-0.90; early AMD: OR, 0.47; 95% CI, 0.24-0.93). There was no significant association between myopia and age-related macular degeneration in male participants and in participants older than 50 years.

CONCLUSIONS

In the Korean adult population, myopia was associated with significantly lower odds of any type of early age-related macular degeneration, particularly in females and in younger age groups.

Ocular Axial Length and Diabetic Retinopathy: The Kailuan Eye Study

Purpose

To examine the role of ocular axial length as an ocular parameter for the prevalence and severity of diabetic retinopathy (DR).

Methods

The cross-sectional Kailuan Diabetic Retinopathy Study included patients with diabetes who participated in the community-based longitudinal Kailuan Study and who had undergone ocular fundus photography. The fundus photographs were graded using the Early Treatment of Diabetic Retinopathy Study criteria.

Results

The study included 1096 patients with diabetes (mean age: 60.8 ± 9.4 years; axial length: 23.37 ± 0.92 mm). In binary regression analysis, a higher DR prevalence was associated with shorter axial length (P = 0.007; odds ratio [OR]: 0.81; 95% confidence interval [CI]: 0.70, 0.95) after adjusting for longer known duration of diabetes (P = 0.02; OR: 1.13; 95%CI: 1.02, 1.24) and higher fasting blood glucose concentration (P < 0.001; OR: 1.38; 95%CI: 1.26, 1.52). A more severe DR stage was associated (regression coefficient r: 0.46) with shorter ocular axial length (P = 0.047; standardized regression coefficient β: -0.06) after adjusting for higher fasting blood glucose (P < 0.001; β: 0.41) and longer known duration of diabetes (P = 0.045; β: 0.07). Longer axial length was associated with a lower DR prevalence (P = 0.003; β: -0.10) after adjusting for younger age (P < 0.001), male sex (P < 0.001), higher body mass index (P = 0.016), and lower fasting blood glucose concentration (P = 0.036).

Conclusions

After adjusting for systemic risk factors, DR prevalence decreased by 19% (95%CI: 5, 30) for each millimeter increase in axial length. With longer axial length being a surrogate for axial myopia, the marked increase in myopia prevalence worldwide may lead to a relative decrease in the prevalence and incidence of DR in future.

Correlation of axial length and myopic macular degeneration to levels of molecular factors in the aqueous

To elucidate the molecular processes associated with the development of myopic macular degeneration (MMD), we measured the intraocular concentrations of molecular factors in emmetropic and myopic eyes. This is a retrospective clinic-based case-control study that included eyes undergoing routine cataract surgery whereby aqueous humour samples were obtained. We measured the concentrations of pigment epithelium derived factor(PEDF), matrix metalloproteinase 2(MMP-2), tissue inhibitor of metalloproteinase(TIMP-2), vascular endothelial growth factor isoform A(VEGF-A), interleukin 8(IL-8), interleukin 6(IL-6), C-reactive protein(CRP), angiopoietin 2(Ang2), and amphiregulin. 38 eyes (axial length (AL): 22.4–32.4 mm), including 12 highly myopic (HM) eyes (AL ≥ 26.5 mm) without MMD and 12 HM eyes with MMD but without neovascularization were included. Eyes with MMD were found to have significantly lower VEGF-A levels (p = 0.007) and higher MMP-2 levels (p = 0.02) than control eyes after adjusting for age and gender. MMP-2 levels correlated positively (r = 0.58, p = 0.002), while VEGF-A levels correlated negatively with longer axial length (r = −0.75, p < 0.001). Both the concentrations of VEGF-A (P = 0.25) and MMP-2 (P = 0.69) were not significantly associated with MMD after adjusting for AL. These findings suggest that the predominant mechanism underlying the development of non-neovascular MMD may be axial elongation, driven in part by MMP-2 related mechanisms.

Refractive Error Has Minimal Influence on the Risk of Age-Related Macular Degeneration: A Mendelian Randomization Study

PURPOSE

To test the hypothesis that refractive errors such as myopia and hyperopia cause an increased risk of age-related macular degeneration (AMD) and to quantify the degree of risk.

DESIGN

Two-sample Mendelian randomization analysis of data from a genome-wide association study.

PARTICIPANTS

As instrumental variables for refractive error, 126 genome-wide significant genetic variants identified by the Consortium for Refractive Error and Myopia and 23andMe Inc. were chosen. The association with refractive error for the 126 variants was obtained from a published study for a sample of 95,505 European ancestry participants from UK Biobank. Association with AMD for the 126 genetic variants was determined from a genome-wide association study (GWAS) published by the International Age-related Macular Degeneration Genomics consortium of 33,526 (16,144 cases and 17,832 controls) European ancestry participants.

METHODS

Two-sample Mendelian randomization (MR) analysis was used to assess the causal role of refractive error on AMD risk, using the 126 genetic variants associated with refractive error as instrumental variables, under the assumption that the relationship between refractive error and AMD risk is linear.

MAIN OUTCOME MEASUREMENT

the risk AMD was caused by a 1-diopter (D) change in refractive error.

RESULTS

MR analysis suggested that refractive error had very limited influence on the risk of AMD. Specifically, 1 D more hyperopic refractive error was associated with an odds ratio (OR) of 1.080 (95% confidence interval [CI], 1.021-1.142; P = 0.007) increased risk of AMD. MR-Egger, MR pleiotropy residual sum and outlier, weighted median, and Phenoscanner-based sensitivity analyses detected minimal evidence to suggest that this result was biased by horizontal pleiotropy.

CONCLUSIONS

Under the assumption of a linear relationship between refractive error and the risk of AMD, myopia and hyperopia only minimally influence the causal risk for AMD. Thus, inconsistently reported strong associations between refractive error and AMD are likely to be the result of noncausal factors such as stochastic variation, confounding, or selection bias.

Small Hard Macular Drusen and Associations in 11- to 12-Year-Old Children in the Copenhagen Child Cohort 2000 Eye Study

Purpose

To assess the prevalence and associations of small hard drusen in a child cohort.

Methods

Cross-sectional study of 11- to 12-year-old Danish children from the population-based Copenhagen Child Cohort 2000 Eye Study. Fovea-centered, 45° color images of both eyes were graded for macular drusen (within one optic-disc-rim-to-fovea distance of the foveal center) and for extramacular drusen. Analyses tested for associations between drusen and anthropometric measures including choroidal thickness.

Results

Gradable fundus images from both eyes were available for 1333 children (640 boys, 693 girls) with a mean (SD) age of 11.7 (0.40) years. One or more small hard macular drusen (diameter <63 μm) were present in 82 (6.2%) right eyes and 82 (6.2%) left eyes and in 147 (11.0%) subjects. Four children (0.30%) had 20 or more small hard macular drusen in one or both eyes. Extramacular small hard drusen were present in 10.7% of children, and 19% of children had such drusen anywhere. The odds for having one or more small hard macular drusen increased with subfoveal choroidal thickness with an odds ratio of 1.15 (95% confidence interval, 1.03-1.28; P = 0.013) per 50-μm thicker choroid, adjusted for age and sex. The association with choroidal thickness was also present for extramacular drusen.

Conclusions

Having one or more small hard macular drusen was common in 11- to 12-year old children and it was associated with a thicker subfoveal choroid. Few children had many small hard drusen. There is no apparent clinical impact of small hard drusen in childhood.

Axial length and its associations in a Russian population: The Ural Eye and Medical Study

Purpose

To assess the normal distribution of axial length and its associations in a population of Russia.

Methods

The population-based Ural Eye and Medical Study included 5,899 (80.5%) individuals out of 7328 eligible individuals aged 40+ years. The participants underwent an ocular and systemic examination. Axial length was measured sonographically (Ultra-compact A/B/P ultrasound system, Quantel Medical, Cournon d'Auvergne, France).

Results

Biometric data were available for 5707 (96.7%) individuals with a mean age of 58.8±10.6 years (range:40–94 years; 25%, 50%, 75% quartile: 51.0, 58.0, 66.0 years, respectively). Mean axial length was 23.30±1.10 mm (range: 19.02–32.87mm; 95% confidence interval (CI): 21.36–25.89; 25%, 50%, 75% quartile: 22.65mm, 23.23mm, 23.88mm, resp.). Prevalences of moderate myopia (axial length:24.5-<26.5mm) and high myopia (axial length >26.5mm) were 555/5707 (8.7%;95%CI:9.0,10.5) and 78/5707 (1.4%;95%CI:1.1,1.7), respectively. Longer axial length (mean:23.30±1.10mm) was associated (correlation coefficient r²:0.70) with older age (P<0.001;standardized regression coefficient beta:0.14), taller body height (P<0.001;beta:0.07), higher level of education (P<0.001;beta:0.04), higher intraocular pressure (P<0.001;beta:0.03), more myopic spherical refractive error (P<0.001;beta:-0.55), lower corneal refractive power (P<0.001;beta:-0.44), deeper anterior chamber depth (P<0.001;beta:0.20), wider anterior chamber angle (P<0.001;beta:0.05), thinner peripapillary retinal nerve fiber layer thickness (P<0.001;beta:-0.04), higher degree of macular fundus tessellation (P<0.001;beta:0.08), lower prevalence of epiretinal membranes (P = 0.01;beta-0.02) and pseudoexfoliation (P = 0.007;beta:-0.02) and higher prevalence of myopic maculopathy (P<0.001;beta:0.08). In that model, prevalence of age-related macular degeneration (any type: P = 0.84; early type: P = 0.46), diabetic retinopathy (P = 0.16), and region of habitation (P = 0.27) were not significantly associated with axial length.

Conclusions

Mean axial length in this typically multi-ethnic Russian study population was comparable with values from populations in Singapore and Beijing. In contrast to previous studies, axial length was not significantly related with the prevalences of age-related macular degeneration and diabetic retinopathy or region of habitation.

Evaluation of the Relationship Between Age-related Macular Degeneration and Refractive Error, Socio-demographic Features, and Biochemical Variables in a Turkish Population

OBJECTIVES

To investigate the relationship between age-related macular degeneration (AMD) and refractive error and axial length, as well as the socio-demographic characteristics and biochemical variables that may affect this relationship.

MATERIALS AND METHODS

A total of 196 eyes of 98 patients over 50 years of age who were diagnosed with AMD at our clinic were included in this cross-sectional study. Early and late AMD findings were categorized according to the age-related eye disease study grading scale. Objective refractive error was measured by autorefractometer, confirmed by subjective examination, and spherical equivalent was calculated. Refractive errors of -0.50 D to 0.50 D were classified as emmetropia, <-0.50 D as myopia, and >0.50 D as hyperopia. Axial length was measured by ultrasonic biometry and values ≤23.00 mm were classified as short, >23.00 and <24.00 mm as normal, and ≥24.00 mm as long axial length. Demographic, systemic, and biochemical parameters of all patients were also investigated.

RESULTS

Hypermetropic refractive error and shorter axial length were significantly more common than the other groups (p<0.01). No differences were observed between early and late stage groups in terms of refractive error and axial length. Patients with myopia had significantly lower values for total cholesterol, triglyceride, fasting blood glucose, and proportion of smokers. Rates of oral nutritional supplement use and fish consumption were significantly higher in the early AMD group. The most common comorbidity among the AMD patients in our study was essential hypertension.

CONCLUSION

Hyperopic refractive error and shorter axial length were found to be associated with AMD. Longitudinal studies including larger patient numbers are needed to elucidate the causal and temporal relationship between hyperopic refractive error and AMD.

Factors Associated with Age-Related Macular Degeneration in Chinese American Adults: The Chinese American Eye Study (CHES)

OBJECTIVE

To assess associations between age-related macular degeneration (AMD) and multiple factors comprising a conceptual model of AMD risk in a population of Chinese Americans, and to draw comparisons with a similar risk assessment of a Latino population.

DESIGN

A cross-sectional population-based study.

PARTICIPANTS

We enrolled 4582 Chinese Americans aged ≥50 residing in Monterey Park, California.

METHODS

Participants completed a comprehensive eye examination, including stereoscopic fundus photography and ocular biometric measurements. Fundus images were graded using a modified version of the Wisconsin Age-Related Maculopathy Grading System.

MAIN OUTCOMES AND MEASURES

Odds ratios for factors significantly modifying the risk of AMD and its related retinal lesions.

RESULTS

Of the eligible participants, 4172 (72%) had fundus photographs gradable for AMD. Early AMD was present in 375 eyes (4.6%), and late AMD was present in 17 (0.2%). Shorter axial length, male sex, older age, and family history of AMD were identified as independent risk factors for prevalent AMD and its characteristic retinal lesions using a conceptual model of potential AMD risk factors. Of 4 AMD risk factors identified for Latinos, 3 (older age, male sex, shorter axial length) overlapped with those identified for Chinese Americans, with an association similar in magnitude and direction. Lower levels of education were a risk factor specific to Latinos. Based on a multivariable logistic regression model, the predicted probability of early AMD was 31% lower among Chinese Americans relative to Latinos (95% confidence interval [CI], 17%-43%). Chinese Americans also had statistically significantly lower odds of any AMD and 2 types of early retinal lesions symptomatic of AMD.

CONCLUSIONS

Factors associated with prevalent AMD are similar for Chinese Americans and Latinos. Chinese Americans who were older, were male, had a family history of AMD, and had a shorter axial length were at an increased risk for AMD compared with those without these risk factors. We observed a significantly lower predicted prevalence of AMD among Chinese Americans compared with Latinos, even after controlling for all relevant covariates, suggesting that additional genetic or lifestyle differences may play an important role in determining AMD risk.

Refractive Error and the Risk of Age-Related Macular Degeneration in the South Korean Population

PURPOSE

We investigated the association between refractive error and the prevalence of age-related macular degeneration (AMD) in a population-based study.

DESIGN

This was a cross-sectional study.

METHODS

Right eyes were included from 14,067 participants aged 40 years and older with gradable fundus photographs and refraction data from the fourth and the fifth Korea National Health and Nutrition Examination Survey 2008 to 2011. Early and late AMD was graded based on the International Age-Related Maculopathy Epidemiological Study Group grading system. Autorefraction data were collected to calculate spherical equivalent refraction in diopters (D) and classified into 4 groups: hyperopia (≥1.0 D), emmetropia (-0.99 to 0.99 D), mild myopia (-1.0 to -2.99 D), and moderate to high myopia (≤-3.0 D).

RESULTS

After adjustment for potential confounders, each diopter increase in spherical equivalent was associated with a 16% [odds ratio (OR), 1.16; 95% confidence interval (CI), 1.08-1.25] and 18% (OR, 1.18; 95% CI, 1.10-1.27) increased risk of any (early + late) and early AMD, respectively. Mild and moderate to high myopia were associated with lower odds of any and early AMD compared with hyperopia (any AMD: OR, 0.62; 95% CI, 0.4-0.95 for mild myopia; OR, 0.41; 95% CI, 0.21-0.81 for moderate to high myopia; early AMD: OR, 0.63; 95% CI, 0.4-0.99 for mild myopia; OR, 0.36; 95% CI, 0.16-0.77 for moderate to high myopia group). There was no association between refractive status and the likelihood of late AMD (P = 0.91).

CONCLUSIONS

Myopia is associated with lower odds of any and early AMD, but not with late AMD in the South Korean population.

The Royal College of Ophthalmologists' National Ophthalmology Database Study of cataract surgery: report 2, relationships of axial length with ocular copathology, preoperative visual acuity, and posterior capsule rupture

PURPOSE

To describe the relationships of axial length with ocular copathology, preoperative visual acuity, and posterior capsule rupture rates in patients undergoing cataract surgery.DesignThe Royal College of Ophthalmologists' National Ophthalmology Database (NOD) study.

METHODS

Anonymised data on 180 114 eyes from 127 685 patients undergoing cataract surgery between August 2006 and November 2010 were collected prospectively from 28 sites. Data parameters included: demographics, biometry, ocular copathology, visual acuity measurements, and surgical complications including posterior capsule rupture, or vitreous loss or both (PCR).

RESULTS

Consultant surgeons performed a higher proportion of operations on eyes whose axial length were at the extremes. Glaucoma and age related macular degeneration were more common in eyes with shorter axial lengths, whilst previous vitrectomy was associated with longer axial lengths. Eyes with brunescent or white cataracts or amblyopia were more common at both axial length extremes. Preoperative visual acuities were similar for eyes with axial length measurements up to approximately 28 mm and worse for eyes with longer axial length measurements. PCR rates showed little change with axial length (overall mean 1.95%, 95% CI: 1.89 to 2.01%), except for a borderline increase in eyes with axial length <20.0 mm where rates were 3.6% (95% CI: 2.0 to 6.3%). The likelihood of PCR in eyes with axial length <20.0 mm was 1.88 times higher than those of ≥20.0 mm (P=0.0373).

CONCLUSION

Rates of ocular comorbidities vary by axial length. PCR rates in eyes with very short or long axial lengths were lower than expected.

Axial length and subfoveal choroidal thickness in individuals with age-related macular degeneration

PURPOSE

To compare axial length (AL) and subfoveal choroidal thickness (SFCT) between individuals with age-related macular degeneration (AMD) and controls with no lesions.

METHODS

This was a case-control study. In total, 853 eyes of 484 patients (>65 years), including 397 eyes at various AMD stages and 456 eyes with no fundus lesions (controls) were recruited. Using color fundus photography, eyes were grouped according to AMD degree. AL was automatically measured using IOL Master and SFCT was manually measured by two independent observers. The associations among age, AL, SFCT, and each AMD grade were analyzed.

RESULTS

Out of 853 eyes, 456 had no lesions, 217 contained drusen only, 134 had early AMD, and 46 had late AMD. The eyes with late AMD were older (p = 0.007) and had longer AL (p ≥ 0.001) and thinner SFCT (p < 0.001) compared with groups of no fundus lesions, drusen only, and early AMD. SFCT in eyes with late AMD decreased by 19.20 μm (p = 0.049), 24.78 μm (p = 0.029), and 15.56 μm (p = 0.162) compared with groups of no fundus lesions, drusen only, and early AMD, respectively. SFCT decreased by 14.18 μm/mm increase in AL (p < 0.001). The odds ratio (OR) for late AMD by longer AL (≥25 mm) and thinner SFCT (<240 μm) was 4.54 (χ² = 9.36; p = 0.002) and 4.86 (χ² = 17.62; p < 0.001), respectively, and was 9.57 (χ² = 18.07; p < 0.001) when both AL ≥ 25 ≥m and SFCT < 240 μm.

CONCLUSION

Eyes with late AMD have distinct reduced SFCT and elongated AL. Eyes with thinner SFCT and longer AL showed high ORs for late AMD and even higher ORs when both factors were simultaneously present. These findings illustrate the crucial pathophysiological role of these two important ocular fac tors and arouse our attention to patients with both characteristics, especially in Asian countries where the prevalence of myopia are disturbingly high.

Intravitreal vascular endothelial growth factor concentration and axial length

BACKGROUND

To examine the intravitreal concentration of vascular endothelial growth factor (VEGF) in dependence of the axial length in eyes without intraocular neovascularization.

METHODS

The concentrations of VEGF in vitreous samples and blood samples of patients undergoing pars plana vitrectomy for treatment of idiopathic macular holes or epiretinal membranes were examined using enzyme-linked immunosorbent assay. Axial length was determined by biometry.

RESULTS

The study included 34 patients with macular holes (n = 21) or epiretinal membranes (n = 13) with a mean age of 62.4 ± 10.5 years (range: 35-76 years) and a mean axial length of 24.1 ± 1.8 mm (range: 21.0-29.1 mm). The intravitreal VEGF concentration (mean: 71.0 ± 63.2 pg/mL) was significantly (P < 0.001) lower than the VEGF concentration in the blood (830 ± 585 pg/mL). Both parameters were significantly associated with each other (P = 0.04; correlation coefficient r = 0.35). The intravitreal VEGF concentration was not significantly associated with gender (P = 0.25) or age (P = 0.48). A higher intravitreal VEGF concentration was significantly associated with a shorter axial length (P = 0.025; r = -0.39) or a higher hyperopic refractive error (P = 0.04; r = 0.35). Neither plasma concentration of VEGF nor the ratio of plasma VEGF concentrations to intravitreal VEGF concentration was significantly associated with axial length (P = 0.89 and P = 0.22, respectively) or with refractive error (P = 0.89 and P = 0.26, respectively).

CONCLUSION

Intravitreal VEGF concentration decreased with increasing axial length. It suggests a diluting effect in eyes with larger intraocular volume and/or a faster turnover rate of VEGF in axially myopic eyes with vitreous liquefaction.

Intracameral interleukin 1β, 6, 8, 10, 12p, tumor necrosis factor α and vascular endothelial growth factor and axial length in patients with cataract

Objective

To assess associations between the aqueous humour concentration of interleukin IL-1β, IL-6, IL-8, IL-10 and IL-12p, tumor necrosis factor α (TNF-α) and vascular endothelial growth factor (VEGF) and axial length in eyes with cataract.

Methods

The hospital-based investigation included patients who underwent cataract surgery between March 2014 and April 2014. Using aqueous humour collected at the start of cataract surgery, the interleukins IL-1β, IL-6, IL-8, IL-10 and IL-12p, TNF-α and VEGF were examined using a cytometric bead array. Axial length was determined by partial coherence laser interferometry (IOL Master).

Results

The study included 33 patients with cataract (33 eyes) with a mean age of 69.2±10.8 years (range:50–87 years) and a mean axial length of 24.7±1.9 mm (range:22.6–31.5 mm). Lower aqueous concentration of VEGF was significantly associated with longer axial length (VEGF concentration (pg/mL) = -5.12 x Axial Length (mm) + 163; correlation coefficient r = -0.41; P<0.001) and more myopic refractive error (VEGF concentration (pg/mL) = 1.27xspherical equivalent (diopters)+44.8; r = 0.383; P = 0.002). The aqueous concentrations of all other substances were not significantly (all P>0.10) associated with axial length or refractive error.

Conclusions

Higher intravitreal concentrations of VEGF were measured in eyes with a longer axial length, while the intraocular concentrations of IL-1β, IL-6, IL-8, IL-10, IL-12p and TNF-α were not correlated with axial length. The lower concentration of VEGF in axially elongated eyes may be one of the reasons for the lower prevalence of age-related macular degeneration and diabetic retinopathy in myopic eyes.

Refractive error and risk of early or late age-related macular degeneration: a systematic review and meta-analysis

OBJECTIVE

To summarize relevant evidence investigating the associations between refractive error and age-related macular degeneration (AMD).

DESIGN

Systematic review and meta-analysis.

METHODS

We searched Medline, Web of Science, and Cochrane databases as well as the reference lists of retrieved articles to identify studies that met the inclusion criteria. Extracted data were combined using a random-effects meta-analysis. Studies that were pertinent to our topic but did not meet the criteria for quantitative analysis were reported in a systematic review instead.

MAIN OUTCOME MEASURES

Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between refractive error (hyperopia, myopia, per-diopter increase in spherical equivalent [SE] toward hyperopia, per-millimeter increase in axial length [AL]) and AMD (early and late, prevalent and incident).

RESULTS

Fourteen studies comprising over 5800 patients were eligible. Significant associations were found between hyperopia, myopia, per-diopter increase in SE, per-millimeter increase in AL, and prevalent early AMD. The pooled ORs and 95% CIs were 1.13 (1.06-1.20), 0.75 (0.56-0.94), 1.10 (1.07-1.14), and 0.79 (0.73-0.85), respectively. The per-diopter increase in SE was also significantly associated with early AMD incidence (OR, 1.06; 95% CI, 1.02-1.10). However, no significant association was found between hyperopia or myopia and early AMD incidence. Furthermore, neither prevalent nor incident late AMD was associated with refractive error. Considerable heterogeneity was found among studies investigating the association between myopia and prevalent early AMD (P = 0.001, I2 = 72.2%). Geographic location might play a role; the heterogeneity became non-significant after stratifying these studies into Asian and non-Asian subgroups.

CONCLUSION

Refractive error is associated with early AMD but not with late AMD. More large-scale longitudinal studies are needed to further investigate such associations.

Racial variations in the prevalence of refractive errors in the United States: the multi-ethnic study of atherosclerosis

PURPOSE

To describe racial variations in the prevalence of refractive errors among adult white, Chinese, Hispanic, and black subjects in the United States.

DESIGN

Cross-sectional data from a prospective cohort study-the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

A total of 6000 adults aged 45 to 84 years living in the United States participated in the study. Refractive error was assessed, without cycloplegia, in both eyes of all participants using an autorefractor. After excluding eyes with cataract, cataract surgery, or previous refractive surgery, the eye with the larger absolute spherical equivalent (SE) value for each participant was used to classify refractive error. Any myopia was defined as SE of -1.0 diopters (D) or less; high myopia was defined as SE of -5.0 D or less; any hyperopia was defined as SE of +1.0 D or more; clinically significant hyperopia was defined as SE of +3.0 D or more. Astigmatism was defined as a cylinder value of +1.0 D or more.

RESULTS

After excluding 508 participants with cataracts in both eyes, 838 participants with cataract surgery, 90 participants with laser refractive surgery, and 134 participants who refused to remove their contact lenses for the refraction measurement, 4430 adults with refractive error assessment in at least 1 eye contributed to the analysis. The prevalence of myopia among MESA participants was 25.1%, with lowest rates in Hispanic participants (14.2%), followed by black (21.5%) and white participants (31.0%), and highest rates in Chinese participants (37.2%). The overall rates of high myopia and astigmatism were 4.6% and 45.0%, respectively, with Chinese subjects also having the highest rates of high myopia (11.8%) and astigmatism (53.4%). The overall prevalence of any hyperopia was 38.2% and clinically significant hyperopia was 6.1%, with Hispanic participants having the highest rates of hyperopia (50.2%) and clinically significant hyperopia (8.8%). In multivariate analyses adjusting for age, sex, race, and study site, higher education level, being employed, and being taller were associated with a higher prevalence of myopia. In contrast, lower educational level and being shorter were associated with a higher prevalence of hyperopia.

CONCLUSIONS

Myopia and astigmatism were most prevalent in the Chinese population, with Chinese subjects having 3 times the prevalence of myopia as Hispanic subjects. Hyperopia was most common in Hispanic subjects. These findings provide further insights into variations in refractive errors among different racial groups and have important implications for the eye care services in the United States.

Refractive errors and age-related macular degeneration: a systematic review and meta-analysis

OBJECTIVE

To evaluate the association between refractive errors and age-related macular degeneration (AMD).

MAIN OUTCOME MEASURES

A clear understanding of the relationship between refractive error and AMD provides insights into the pathophysiology of AMD.

METHODS

We searched PubMed and Embase from their inception to July 2012 for population-based studies with data on refractive error and AMD assessed from retinal photographs at baseline and follow-up. We performed separate meta-analyses for cross-sectional studies and cohort studies using adjusted odds ratios (ORs) and hazard ratios (HRs) under random effects models, respectively.

RESULTS

Analysis of the 6 cross-sectional studies showed that hyperopia was associated with higher odds of prevalent AMD (pooled OR hyperopia vs. emmetropia: 1.16; 95% confidence interval [CI], 1.04-1.29) and that myopia was associated with lower odds of prevalent AMD (pooled OR myopia vs. emmetropia: 0.75; 95% CI, 0.61-0.92). Analysis from the 3 cohort studies showed nonsignificant associations. Analysis of the 5 cross-sectional and 2 cohort studies showed that each diopter increase in spherical equivalent was associated with increased odds of both prevalent (pooled OR, 1.09; 95% CI, 1.06-1.12) and incident (pooled HR, 1.06; 95% CI, 1.02-1.10) AMD. In 3 cross-sectional studies with data on axial length, each millimeter increase in axial length was associated with a decreased odd of prevalent AMD (pooled OR, 0.76; 95% CI, 0.69-0.85).

CONCLUSIONS

Refractive error is associated with AMD, although a temporal relationship cannot be determined on the basis of current evidence. Ophthalmologists should be aware that risk of AMD clinically seems to vary by refractive status.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Age-related macular degeneration revisited--piecing the puzzle: the LXIX Edward Jackson memorial lecture

PURPOSE

To present the current understanding of age-related macular degeneration (AMD) pathogenesis, based on clinical evidence, epidemiologic data, histopathologic examination, and genetic data; to provide an update on current and emerging therapies; and to propose an integrated model of the pathogenesis of AMD.

DESIGN

Review of published clinical and experimental studies.

METHODS

Analysis and synthesis of clinical and experimental data.

RESULTS

We are closer to a complete understanding of the pathogenesis of AMD, having progressed from clinical observations to epidemiologic observations and clinical pathologic correlation. More recently, modern genetic and genomic studies have facilitated the exploration of molecular pathways. It seems that AMD is a complex disease that results from the interaction of genetic susceptibility with aging and environmental factors. Disease progression also seems to be driven by a combination of genetic and environmental factors.

CONCLUSIONS

Therapies based on pathophysiologic features have changed the paradigm for treating neovascular AMD. With improved understanding of the underlying genetic susceptibility, we can identify targets to halt early disease and to prevent progression and vision loss.

Drusen prevalence and pigmentary changes in Caucasians aged 18-54 years

AIMS AND PURPOSE

The aim of this study was to describe the prevalence and characteristics of drusen and pigmentary changes in a middle-aged population.

METHODS

Retinal images from 500 individuals aged 18-54 years were included. The source of participants was two UK optometry practices. Retinal images were graded using the Wisconsin Age-Related Maculopathy Grading System. However, owing to the relatively young age of the population studied, a new category of drusen of smaller size (<31.5 μm) was introduced.

RESULTS

Drusen were identified within the central macular grid in 91.48% of all gradable eyes and in 444 subjects. Drusen sized <31.5 μm were present in 89.7% of eyes, drusen sized >31.5 μm and <63 μm were present in 45.9% of all eyes and drusen >63 μm and <125 μm were present in only 1.7% of eyes. No eye had drusen larger or equal to 125 μm. Very few eyes (1.2%) showed pigmentary changes within the grid. Drusen load increased with increasing age, P <0.001.

CONCLUSIONS

The frequency of drusen in a younger Caucasian population aged 18-54 years is high, with 91.48% of all gradable eyes having drusen. The most frequent drusen subtype was hard distinct drusen <31.5 μm. No druse greater or equal in size to 125 μm was seen. Pigmentary changes are rare.

Prevalence of age-related macular degeneration in elderly Caucasians: the Tromsø Eye Study

PURPOSE

To describe the sex- and age-specific prevalence of drusen, geographic atrophy, and neovascular age-related macular degeneration (AMD).

DESIGN

Population-based, cross-sectional study.

PARTICIPANTS

Caucasian adults aged 65 to 87 years from the 6th Tromsø Study, a population-based study conducted in 2007-2008 in the municipality of Tromsø, Norway.

METHODS

Digital color fundus photographs were graded for predominant phenotype based on drusen size, geographic atrophy, and neovascular AMD.

MAIN OUTCOME MEASURES

Age-related macular degeneration.

RESULTS

A total of 3025 subjects participated; 89% of those were invited to the eye examinations. Gradable photographs were available for 2631 persons (mean age 72.3 years). Drusen 63-125 μm as the predominant phenotype were found in 34.9% of participants (95% confidence interval [CI], 33.1-36.8), drusen >125 μm were found in 24.1% (95% CI, 22.5-25.8), geographic atrophy was found in 1.0% of participants (95% CI, 0.6-1.4), and neovascular AMD was found in 2.5% of participants (95% CI, 1.9-3.1). Bilateral involvement of late AMD was present in 1.1% of the sample. Eyes with late AMD had a significantly lower refractive error (spherical equivalent 0.078 vs. 0.99 diopters, P<0.0001), and 42.5% of eyes had Snellen visual acuity ≤ 0.32.

CONCLUSIONS

The prevalence of AMD among the elderly persons in this study was similar to rates in other Caucasian populations. Late AMD was present in 10.9% of subjects aged 80 years or more. No sex differences in prevalence rates of large drusen or late AMD were observed. Lower refractive error was observed in eyes with late AMD than in eyes without late AMD.

Associations of early age-related macular degeneration with ocular and general parameters. The Central India Eyes and Medical Study

PURPOSE

To assess associations between age-related macular degeneration (AMD) and ocular and general parameters.

METHODS

The Central India Eye and Medical Study, a population-based study performed in rural Central India, included 4711 subjects (aged 30+ years) out of 5885 eligible subjects (response rate: 80.1%). Fundus photographs were assessed using the Wisconsin Age-Related Maculopathy Grading system.

RESULTS

Fundus photographs were available for 4542 (96.4%) subjects. Early AMD was present in 215/4542 subjects (4.7 ± 0.3%), and late AMD was detected in 8/4542 (0.2 ± 0.03%) subjects. After adjustment for age, prevalence of AMD was significantly associated with hyperopic refractive error (p = 0.001), shorter axial length (p = 0.01), and higher corneal refractive power (p = 0.02). Each dioptre increase in hyperopic refraction or each millimetre decrease in axial length was associated with a 15% [odds ratio (OR):1.15; 95% confidence interval (CI): 1.06, 1.24] and 19% (OR: 0.81; 95%CI: 0.69, 0.95) increased probability of early AMD, respectively. AMD was not significantly associated with blood pressure, serum concentration of cholesterol, glycosylated haemoglobin Hb1Ac, high-density lipoproteins and postprandial glucose, gender, level of education, any parameter of smoking, alcohol consumption, psychiatric depression or of daily activities, anterior chamber depth, lens thickness, intraocular pressure, size of the optic disc, neuroretinal rim and parapapillary atrophy, nor amount of nuclear cataract and status after cataract surgery. If the statistical analysis was adjusted for age and refractive error, age-related macular degeneration was marginally significantly associated with a low intake of fruits (p = 0.06).

CONCLUSIONS

Hyperopia (and short axial length) besides age was the single most important associated factor for AMD in adult Indians.

Association of risk factors for choroidal neovascularization in age-related macular degeneration with decreased foveolar choroidal circulation

PURPOSE

To investigate the relationship between known risk factors for age-related macular degeneration (AMD) progression and foveolar choroidal circulation in eyes with nonexudative AMD.

DESIGN

Cross-sectional study of nonexudative AMD.

METHODS

Laser Doppler flowmetry measurements of relative choroidal blood velocity, choroidal blood volume (ChBVol), and choroidal blood flow (ChBFlow) were obtained in the center of the fovea of 273 study eyes of 204 AMD patients investigated at the Scheie Eye Institute, University of Pennsylvania Medical School. All study eyes had visual acuity of 20/40 or better, good fixation, no other intraocular pathologic features, and no evidence of choroidal neovascularization. RPE hypertrophy was determined from color fundus photographs by trained masked graders at the Scheie Image Reading Center. Correlation analysis and multivariate linear regression analysis with adjustments for significant covariates were carried out.

RESULTS

A significant inverse correlation was observed between age and ChBFlow (r = -0.36; P < .0001), and ChBVol (r = -0.28; P < .0001), but not for choroidal blood velocity. A significant inverse correlation was observed between spherical equivalent and ChBFlow (r = -0.21; P = .006) and ChBVol (r = -0.14; P = .04), but not for choroidal blood velocity. ChBFlow and ChBVol were significantly lower in patients with a history of hypertension (P < or = .003) and in eyes with retinal pigment epithelium hypertrophy (P < or = .04), respectively.

CONCLUSIONS

All the above-described risk factors for AMD development and progression are associated with decreased choroidal circulatory parameters, suggesting that decreases in choroidal circulatory parameters may be involved in the development of AMD.

ARMS2/HTRA1 and CFH polymorphisms are not associated with choroidal neovascularization in highly myopic eyes of the elderly Japanese population

PURPOSE

The purpose of this study was to investigate whether the genetic risk factors of age-related macular degeneration (AMD) are associated with the development of choroidal neovascularization (CNV) in highly myopic eyes of elderly Japanese.

METHODS

Highly myopic elderly Japanese patients with and without CNV were genotyped for three AMD-associated single nucleotide polymorphisms (SNPs), namely rs10490924 (A69S) of ARMS2, rs11200638 of HTRA1, and rs1061170 (Y402H) of complement factor H (CFH), with the TaqMan SNP assay. One hundred and eighty-three unrelated highly myopic (axial lengths>26.00 mm or refractive errors>-6.0 diopters) Japanese patients with CNV who were >or=50 years of age (mean age+/-standard deviation of 62.7+/-6.3 years) and 170 highly myopic patients without CNV who were >or=50 years old (62.3+/-7.1 years) were studied. The differences in the genotypic distributions for the three SNPs between the two groups were tested with the Trend chi2 test, and logistic regression analyses were performed for age and gender adjustment.

RESULTS

No significant difference was detected in the distribution of the three SNPs, rs10490924 (P>0.1), rs11200638 (P>0.1), and rs1061170 (P>0.5), between the two groups even after adjustments for age and gender differences.

CONCLUSION

The genetic risk factors of AMD related to these SNPs do not contribute significantly to the development of CNV in a highly myopic elderly Japanese population.

Prevalence and progression of myopic retinopathy in Chinese adults: the Beijing Eye Study

PURPOSE

To determine the prevalence and progression of myopic retinopathy in Chinese adults.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

The Beijing Eye Study 2001 included 4439 subjects of 5324 individuals who were invited to participate (response rate, 83.4%); the eligibility criterion was an age of 40+ years. The study was repeated in 2006, with 3251 subjects (73.2%) participating.

METHODS

The participants underwent a detailed eye examination, including fundus photography. Myopic retinopathy was defined by posterior staphylomata, lacquer cracks, Fuchs' spot of the macula, and myopic chorioretinal atrophy at the posterior pole. Parapapillary atrophy was assessed separately.

MAIN OUTCOME MEASURES

Prevalence of myopic retinopathy and its change during a follow-up of 5 years.

RESULTS

After exclusion of pseudophakic or aphakic eyes, and eyes without assessable fundus photographs, 4319 subjects (97.3%) were included in the present study. Myopic retinopathy was present in 198 eyes (2.3%+/-0.2%; 95% confidence interval [CI], 2.0-2.6) of 132 participants (3.1%). Myopic retinopathy was significantly associated with higher age (P<0.001), worse best-corrected visual acuity (P<0.001), deeper anterior chamber (P = 0.04), larger optic disc (P<0.001), less age-related macular degeneration (P = 0.02; odds ratio [OR] 0.90), and greater prevalence of open-angle glaucoma (P<0.001; OR 4.42). Myopic retinopathy was not associated significantly (P>0.20) with body height and weight, gender, rural versus urban region of residence, level of education, intraocular pressure, or central corneal thickness. The prevalence of myopic retinopathy increased significantly (P<0.001) with increasing myopic refractive error, from 3.8% in eyes with a myopic refractive error of < -4.0 diopters to 89.6% in eyes with a myopic refractive error of at least -10.0 diopters. At the 5-year follow-up examination, enlargement of the chorioretinal atrophy at the posterior fundus was observed in 9% of the eyes.

CONCLUSIONS

Myopic retinopathy was present in 3.1% of subjects aged 40+ years who resided in the Greater Beijing area. Myopic retinopathy was associated with increased age, worse best-corrected visual acuity, deeper anterior chamber, larger optic disc, less age-related macular degeneration, and higher prevalence of open-angle glaucoma.

Ocular risk factors for age-related macular degeneration: the Los Angeles Latino Eye Study

PURPOSE

To assess the association between ocular factors and age-related macular degeneration (AMD) in Latinos.

DESIGN

Population-based, cross-sectional study of 6357 self-identified Latinos aged 40 years and older.

METHODS

Ophthalmic examination included subjective refraction, measurement of axial length, evaluation of iris color, Lens Opacities Classification System II (LOCS II) grading of cataracts, and stereoscopic macular photographs for AMD lesions. Generalized estimating equation analysis incorporated data from both eyes to estimate odds ratios (OR) adjusted for covariates.

RESULTS

After controlling for confounders (age, gender, and smoking), prior cataract surgery was associated with advanced AMD (OR, 2.8; 95% CI, 1.01, 7.8), increased retinal pigment (OR, 1.6; 95% CI, 1.02, 1.5), and retinal pigment epithelial depigmentation (OR, 2.2; 95% CI, 1.1, 4.4). The presence of any lens opacity was associated with soft drusen (OR, 1.2; 95% CI, 1.002, 1.5). Longer axial length (per mm) was associated with decreased odds of soft drusen, increased retinal pigment, and geographic atrophy (GA) (ORs, 0.8 [95% CI, 0.7, 0.9], 0.8 [95% CI, 0.7, 0.9], 0.7 [95% CI, 0.5, 0.9], respectively). Myopia was inversely associated with soft drusen (OR, 0.8; 95% CI, 0.7, 0.99). Lighter-colored irises were associated with GA (OR, 5.0; 95% CI, 1.0, 25.3).

CONCLUSIONS

Cross-sectional associations of ocular factors such as cataract, cataract surgery, and refractive errors with early AMD lesions found in Latinos are consistent with those in non-Hispanic Whites. Additionally, prior cataract surgery was associated with advanced AMD.