Age-Related Eye Disease Study Research Group. Risk factors associated with age-related macular degeneration. A case-control study in the age-related eye disease study: Age-Related Eye Disease Study Report Number 3

Zinc deficiency as possible link between immunosenescence and age-related diseases

As global life expectancy increases, research reveals a critical challenge in aging: the progressive deterioration of immune function, termed immunosenescence. This age-related immune decline is characterized by a complex dysregulation of immune responses, which leaves older adults increasingly vulnerable to infections, chronic inflammatory states, and various degenerative diseases. Without intervention, immunosenescence significantly contributes to morbidity and mortality among the elderly, intensifying healthcare burdens and diminishing quality of life on both individual and societal levels. This review explores the essential role of zinc, a trace element critical for immune health, in mitigating the impact of immunosenescence and slowing the cascade of immunological dysfunctions associated with aging. By modulating the activity of key immune cells and pathways, zinc supplementation emerges as a promising approach to strengthen immunity, reduce oxidative stress, and counteract "inflammaging," a state of chronic, low-grade inflammation that accelerates tissue damage and drives disease progression. Zinc's involvement in cellular defense and repair mechanisms across the immune system highlights its ability to enhance immune cell functionality, resilience, and adaptability, strengthening the body's resistance to infection and its ability to manage stressors that contribute to diseases of aging. Indeed, zinc has demonstrated potential to improve immune responses, decrease inflammation, and mitigate the risk of age-related conditions including diabetes, depression, cardiovascular disease, and vision loss. Given the prevalent barriers to adequate zinc intake among older adults, including dietary limitations, decreased absorption, and interactions with medications, this review underscores the urgent need to address zinc deficiency in aging populations. Recent findings on zinc's cellular and molecular effects on immune health present zinc supplementation as a practical, accessible intervention for supporting healthier aging and improving quality of life. By integrating zinc into targeted strategies, public health efforts may not only sustain immunity in the elderly but also extend healthy longevity, reduce healthcare costs, and potentially mitigate the incidence and impact of chronic diseases that strain healthcare systems worldwide.

Evaluation of the macula pigment optical density by a psychophysical test in dry age-related macular degeneration

PurposeTo evaluate the macular pigment optical density (MPOD) in dry age-related macular degeneration (AMD).MethodsThis prospective study included 68 dry AMD patients and, as the control group, 91 healthy volunteers. Age, gender, family history, smoking, alcohol, hypertension, hyperlipidemia, height, weight, dietary lutein intake, and use of lutein-zeaxanthin (L-Z) were questioned. Full ophthalmic examination was performed. Color fundus photography and fundus autofluorescence (FAF) images were recorded. MPOD was measured by color perimetry (CP) every 3 months for 9 months in the dry AMD group, and 1 time at the beginning of the study in the control group. 6 mg/day lutein or 10 mg/day L and 2 mg/day Z were started in non-users.ResultsSmoking, obesity, family history, light iris color, and hyperlipidemia were seen more frequently in the AMD group. Average MPOD values in the AMD group were; 3.69 ± 1.82 (baseline), 4.74 ± 1.29 (3rd month), 4.99 ± 1.27 (6th month), and 5.02 ± 1.35 (9th month) dB, respectively. In the control group, the average MPOD was 4.97 ± 1.27 dB. At the baseline, the MPOD of the AMD group was significantly lower than the control group. Smoking, obesity, poor dietary lutein intake, light iris color, and hyperlipidemia were associated with low MPOD.DiscussionThe relationship between MPOD and AMD is controversial in the literature. Low MPOD and AMD may be related depending on our results. Quit smoking, and having a rich dietary L-Z intake are important for preventing AMD progression. The results of the CP are consistent with the other psychophysical tests.

Dopaminergic Therapies May Decrease Risk of Early and Intermediate Non-exudative Age-related Macular Degeneration Progression

BACKGROUND AND OBJECTIVE

Age-related macular degeneration (AMD) is a leading cause of vision loss, with progression to geographic atrophy (GA) posing a significant challenge. This study aimed to assess whether dopaminergic therapies (DMTs) reduce risk of AMD progressing to GA.

PATIENTS AND METHODS

A retrospective cohort study analyzed electronic health records of 320 patients (449 eyes) with early or intermediate nonexudative AMD at Duke Eye Center from 2014 to 2024. Of these, 80 patients (110 eyes) were on DMTs, and 240 (339 eyes) served as controls. GA progression was evaluated annually over 5 years.

RESULTS

GA progression was lower in the DMT group across all intervals, with lifetime rates of 9.4% in the non-DMT group versus 2.7% in the DMT group (P < 0.05). Multivariate analysis showed a significant protective effect (odds ratio 0.08, P < 0.001).

CONCLUSION

DMTs may significantly reduce risk of AMD progressing to GA, warranting further research. [Ophthalmic Surg Lasers Imaging Retina 2025;56:XX-XX.].

Possible Association Between Dopamine Antagonists and Increased Conversion to Exudative Age-Related Macular Degeneration

Purpose: To investigate whether modulating dopamine signaling affects conversion to exudative age-related macular degeneration (AMD). Methods: A retrospective cohort study was performed using the Duke Epic database. Eyes from patients with a diagnosis of nonexudative AMD with at least 1 year of follow-up were evaluated for conversion to exudative AMD. Eyes with an AMD diagnosis were evaluated for age, sex, smoking history, hypertension, Age-Related Eye Disease Study (AREDS) or AREDS2 prescription, dopamine-modulating therapy prescription, and indication for dopamine-modulating therapy. Generalized estimating equations were used to calculate odds ratios for individual variables on conversion from nonexudative to exudative AMD. Results: Five hundred fifty-eight eyes of 354 patients with an initial diagnosis of nonexudative AMD were evaluated for conversion to exudative AMD. Conversion to exudative AMD was significantly higher in patients who had been on dopamine antagonist therapies for at least 3 years than in patients who were not on any dopamine-modulating therapies. After controlling for other variables, dopamine antagonists were associated with an increased risk for conversion to exudative AMD at 3 years of follow-up (P = .005). Conclusions: These findings suggest that antagonizing dopamine signaling may be associated with the development of macular neovascularization in eyes with nonexudative AMD. Although the data are observational, these findings warrant further investigation of dopamine signaling in conversion to exudative AMD.

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 the dietary omega-6 to omega-3 fatty acid ratio and age-related macular degeneration in Korean adults

BACKGROUND

Long-chain polyunsaturated fatty acids of the omega-6 and omega-3 families affect processes implicated in vascular and neural retinal disease pathogenesis. This study aimed to investigate the association between the dietary omega-6 to omega-3 fatty acid ratio and age-related macular degeneration (AMD).

METHODS

We conducted a cross-sectional analysis using a nationwide representative sample of older adults (≥ 50 years), including 1,944 men and 2,592 women, from the Korea National Health and Nutrition Examination Survey (2017-2018). Omega-6 and omega-3 fatty acid intakes were collected through a 24-hour recall method and used to calculate the omega-6 to omega-3 fatty acid ratio. Associations between the ratio and AMD were determined using odds ratios (ORs) from multivariate logistic regressions.

RESULTS

The prevalence of AMD was 19.8% and 17.7% in Korean men and women, respectively. In women, the multivariable-adjusted OR for incurring AMD was significantly higher in the 2nd (OR = 1.36; 95% CI = 1.02-1.81) and 3rd (OR = 1.36; 95% CI = 1.02-1.83) tertiles of the dietary omega-6 to omega-3 fatty acid ratio than in the 1st tertile (OR = 1, the reference OR) (P = 0.036 for this trend). However, this association was not observed in men.

CONCLUSIONS

These results suggest that high omega-6 to omega-3 fatty acid ratios may be associated with an increased prevalence of AMD among Korean women.

Association between the weight-adjusted waist index and age-related macular degeneration in US adults aged≥40 years: the NHANES 2005-2008

Objective

The association between the weight-adjusted waist index (WWI) and age-related macular degeneration (AMD) in US adults aged 40 years and older is unknown. The goal of this study was to ascertain a possible association between the two.

Methods

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) in the US from 2005 to 2008. The WWI was calculated by dividing waist circumference (WC) by the square root of body weight (kg). AMD was diagnosed based on distinctive features observed in the fundus, using a standard classification system. Weighted logistic regression analyses were conducted to investigate the association between the WWI and AMD. Spline smoothing and threshold effects were applied to explore non-linear correlations. Subgroup analyses were performed to identify underlying covariates affecting this relationship. In addition, receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive power of the WWI for AMD.

Results

A total of 5,132 participants were enrolled in this study. The results showed a significant positive association between the WWI and risk of AMD (OR = 1.76 (1.52, 2.04); p < 0.0001). When the WWI was categorized into tertiles, the highest group exhibited a stronger association compared to the lowest tertile (OR = 2.90 (2.18, 3.86); p < 0.0001) in model 1. The subgroup analyses and interaction tests indicated that the relationship between the WWI and AMD was stable across various populations. The spline smoothing and threshold effects showed a positive non-linear correlation between the WWI and AMD incidence. Furthermore, compared to body mass index (BMI), WC, and weight, the WWI showed better predictability for AMD, as shown by the ROC analysis.

Conclusion

There exists a positive non-linear association between the WWI and AMD in US adults aged 40 years and older. The WWI-related obesity management is necessary for the prevention and treatment of AMD.

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.

Resveratrol Protects Photoreceptors in Mouse Models of Retinal Degeneration

Photoreceptor/retinal degeneration is the major cause of blindness. Induced and inherited mouse models of retinal degeneration are valuable tools for investigating disease mechanisms and developing therapeutic interventions. This study investigated the potential of the antioxidant resveratrol to relieve photoreceptor degeneration using mouse models. Clinical studies have shown a potential association between thyroid hormone (TH) signaling and age-related retinal degeneration. Excessive TH signaling induces oxidative stress/damage and photoreceptor death in mice. C57BL/6 (rod-dominant) and Nrl-/- (cone-dominant) mice at postnatal day 30 (P30) received triiodothyronine (T3) via drinking water (20 µg/mL) with or without concomitant treatment with resveratrol via drinking water (120 µg/mL) for 30 days, followed by evaluation of photoreceptor degeneration, oxidative damage, and retinal stress responses. In experiments using Leber congenital amaurosis model mice, mother Rpe65-/- and Rpe65-/-/Nrl-/- mice received resveratrol via drinking water (120 µg/mL) for 20 days and 10-13 days, respectively, beginning on the day when the pups were at P5, and pups were then evaluated for cone degeneration. Treatment with resveratrol significantly diminished the photoreceptor degeneration induced by T3 and preserved photoreceptors in Rpe65-deficient mice, manifested as preserved retinal morphology/outer nuclear layer thickness, increased cone density, reduced photoreceptor oxidative stress/damage and apoptosis, reduced upregulation of genes involved in cell death/inflammatory responses, and reduced macroglial cell activation. These findings demonstrate the role of oxidative stress in photoreceptor degeneration, associated with TH signaling and Rpe65 deficiency, and support the therapeutic potential of resveratrol/antioxidants in the management of retinal degeneration.

Machine learning derived retinal pigment score from ophthalmic imaging shows ethnicity is not biology

Few metrics exist to describe phenotypic diversity within ophthalmic imaging datasets, with researchers often using ethnicity as a surrogate marker for biological variability. We derived a continuous, measured metric, the retinal pigment score (RPS), that quantifies the degree of pigmentation from a colour fundus photograph of the eye. RPS was validated using two large epidemiological studies with demographic and genetic data (UK Biobank and EPIC-Norfolk Study) and reproduced in a Tanzanian, an Australian, and a Chinese dataset. A genome-wide association study (GWAS) of RPS from UK Biobank identified 20 loci with known associations with skin, iris and hair pigmentation, of which eight were replicated in the EPIC-Norfolk cohort. There was a strong association between RPS and ethnicity, however, there was substantial overlap between each ethnicity and the respective distributions of RPS scores. RPS decouples traditional demographic variables from clinical imaging characteristics. RPS may serve as a useful metric to quantify the diversity of the training, validation, and testing datasets used in the development of AI algorithms to ensure adequate inclusion and explainability of the model performance, critical in evaluating all currently deployed AI models. The code to derive RPS is publicly available at: https://github.com/uw-biomedical-ml/retinal-pigmentation-score .

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Global burden of low vision and blindness due to age-related macular degeneration from 1990 to 2021 and projections for 2050

BACKGROUND

Age-related macular degeneration (AMD) is a leading cause of blindness and low vision worldwide. This study examines the global burden and trends in AMD-related low vision and blindness from 1990 to 2021, with projections through 2050.

METHODS

Data were obtained from the 2021 Global Burden of Disease (GBD 2021) study, covering 204 countries and regions. Key metrics, including the prevalent case numbers, annual disability-adjusted life years (DALYs), age-standardized prevalence rates (ASPR), and age-standardized DALY rates (ASDALYR), specific to low vision and blindness due to AMD, were calculated per 100,000 population. Trend analysis used the estimated annual percentage change (EAPC) method, and K-means clustering identified regions with similar burdens and trends. Autoregressive Integrated Moving Average(ARIMA) and Exponential Smoothing(ES) models provided future projections.

RESULTS

Globally, the total number of prevalent cases and DALYs has substantially increased. The number of prevalent cases of low vision and blindness due to AMD increased from 3,640,180 (95% UI: 3,037,098 - 4,353,902) in 1990 to 8,057,521 (95% UI: 6,705,284-9,823,238) in 2021. DALYs increased from 302,902 (95% UI: 206,475 - 421,952) in 1990 to 578,020 (95% UI: 401,241-797,570) in 2021. From 1990 to 2021, both the ASPR and ASDALYR for AMD-related low vision and blindness showed a downward trend. The ASPR was 94 (95% UI: 78.32-114.42) per 100,000 population, with an EAPC of -0.26 (95% CI: -0.31 to -0.22), and the ASDALYR was 6.78 (95% UI: 4.7-9.32) per 100,000 population, with an EAPC of -0.94 (95% CI: -1.01 to -0.88). The disease burden of AMD-related low vision and blindness increases with age, and the burden for female patients is slightly higher than for males. Regional stratification by the Socio-Demographic Index (SDI) shows that the burden of AMD-related low vision and blindness in areas with low SDI is higher than in areas with high SDI. From 1990 to 2021, notable increases in ASPR and ASDALYR were observed mainly in the southern and central regions of sub-Saharan Africa. Moreover, the increases in prevalence and DALYs vary by region, country, and level of socioeconomic development. The ARIMA model predicts that by 2050, the number of prevalent cases of low vision and blindness due to AMD will reach 13,880,610(95% CI: 9,805,575-17,955,645), and the DALYs will be 764,731(95% CI: 683,535-845,926). The ES model predicts that by 2050, the number of prevalent cases of AMD-related low vision and blindness will reach 9,323,124(95% CI: 5,222,474-13,423,774), and the DALYs will be 641,451 (95% CI: 383,588-899,318).

CONCLUSION

This study indicates that between 1990 and 2021, the global prevalent cases and DALYs caused by AMD-related low vision and blindness have increased over the past three decades, correlating with factors such as age, gender, socioeconomic status, and geographical location. Predictive models indicate that as the population ages, the number of patients with low vision and blindness due to AMD, along with associated DALYs, will continue to rise. By 2050, it is expected that over 9 million people worldwide will be affected by AMD-related vision loss, with women being particularly impacted. These findings can provide data support for public health planning, resource allocation, and the formulation of medical policies, ensuring an effective response to the challenges posed by the future increase in AMD-related low vision and blindness.

A Comprehensive Health Screening Program Reveals the Prevalence of and Risk Factors for Age-Related Macular Degeneration: A Cross-Sectional Analysis

Background/Objectives: We investigated the prevalence of age-related macular degeneration (AMD) and associated risk factors in Korean subjects who underwent comprehensive health screening examinations. Methods: This single health screening center-based cross-sectional study included a total of 73,574 consecutive participants older than 30 years who underwent a health screening examination, including fundus photography, between October 2003 and December 2010. Weighted prevalence and risk factors for AMD were evaluated. Logistic regression was used to identify AMD risk factors. Results: The weighted prevalence of AMD was 15.42%, with a prevalence of 3.34% among people in their 30s. Advanced age significantly increased the risk for both early/intermediate AMD (p < 0.001 across the age groups of 40, 50, 60, and 70+ years) and advanced AMD (p <0.001 for the age groups of 60 and 70+ years). The male sex was strongly associated with an increased risk of both early/intermediate and advanced AMD (p < 0.001 for both). Retinal arteriosclerosis, whether low- or high-grade, was linked to early/intermediate AMD (p < 0.001 for both grades), whereas only high-grade arteriosclerosis was linked to advanced AMD (p < 0.001). Additionally, hypertension (p < 0.001), the hepatitis B carrier status (p < 0.001), elevated mean corpuscular volume (p < 0.001), and lower serum uric acid levels (p = 0.014) were associated with early/intermediate AMD. Higher education levels protected against early/intermediate AMD (p = 0.004 for high school graduates, p < 0.001 for ≥college graduates). Higher serum inorganic phosphate levels (p = 0.002) and lower total serum ALB levels (p = 0.005) were significant risk factors for advanced AMD. Conclusions: Korean individuals as young as 30 years old are at risk of AMD. This study newly identified associations between retinal arteriosclerosis and both early/intermediate and advanced AMD, as well as associations between serum inorganic phosphate levels and total ALB levels with advanced AMD.

Bridging the gap of vision restoration

Retinitis pigmentosa (RP) and Age-Related Macular Degeneration (AMD) are similar in that both result in photoreceptor degeneration leading to permanent progressive vision loss. This affords the possibility of implementing vision restoration techniques, where light signaling is restored to spared retinal circuitry to recreate vision. There are far more AMD patients (Wong et al., 2014), yet more resources have been put towards researching and developing vision restoration strategies for RP despite it rarity, because of the tractability of RP disease models. The hope is that these therapies will extend to the AMD population, however, many questions remain about how the implementation of prosthetic or optogenetic vision restoration technologies will translate between RP and AMD patients. In this review, we discuss the difference and similarities of RP and AMD with a focus on aspects expected to impact vision restoration strategies, and we identify key gaps in knowledge needed to further improve vision restoration technologies for a broad patient population.

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.

Factors Affecting Visual Acuity After Anti-Vascular Endothelial Growth Factor Therapy in Neovascular Age-Related Macular Degeneration: A Multicenter Study in Japan

Background/Objectives: Anti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for neovascular age-related macular degeneration (nvAMD). While proactive and adequate treatment generally leads to better visual outcomes, various factors, including the disease type, ocular findings, lifestyle, and systemic status, affect the visual prognosis in clinical settings. This study aimed to identify the factors that affect the visual prognosis in patients with nvAMD treated with anti-VEGF therapy. Methods: We conducted a multicenter retrospective cohort study at eight tertiary referral centers in Japan, where we reviewed the medical records of patients newly diagnosed with nvAMD between January 2014 and December 2019. These patients had started treatment with either ranibizumab (0.5 mg) or aflibercept (2.0 mg) and were followed for at least 1 year. We evaluated the impact of the disease type, systemic factors, and initial fundus findings on the best-corrected visual acuity (BCVA) at 1 year. Results: This study included 182 patients (129 men, 53 women), with a mean age of 75.0 ± 8.6 years. The disease types were categorized as typical AMD (53%), polypoidal choroidal vasculopathy (PCV) (43%), and retinal angiomatous proliferation (RAP) (4%). Univariate analysis identified age, the baseline logarithm of the minimum angle of resolution BCVA, intraretinal fluid (IRF), pigment epithelial detachment (PED), and subretinal hyperreflective material (SHRM). Multivariate analysis identified the following significant risk factors associated with vision worsening: age, smoking history, diabetes, and the presence of IRF and PED. Conclusions: The presence of IRF, PED, and SHRM at the start of treatment and a history of smoking and diabetes may be associated with a poor visual prognosis in patients with nvAMD.

Associations of mediterranean diet score and age-related macular degeneration in Korean elderly

BACKGROUND

Previous studies have reported associations between individual nutrients or specific foods and the risk of age-related macular degeneration (AMD). However, the relationship between overall dietary quality, specifically the alternative Mediterranean diet (aMED) score, and AMD remains unclear. Therefore, this study aimed to investigate the association between the aMED score, as an indicator of overall diet quality, and AMD in the Korean population.

METHODS

We conducted a cross-sectional analysis using nationally representative samples of older adults aged ≥ 65 years (895 men and 1,191 women) from the Korea National Health and Nutrition Examination Survey (2017-2018). Food intake and the aMED score were estimated using 24-h recall. AMD was diagnosed by an ophthalmologist based on fundus photography. The associations of aMED score tertiles with AMD were determined using odds ratios (ORs) from multivariate logistic regressions.

RESULTS

Multiple logistic regression analysis revealed a significantly negative association between the aMED score and AMD (adjusted ORs = 0.58; 95% confidence interval = 0.39-0.88; p-trend = 0.021) in older men after adjusting for confounding factors such as age, body mass index, family monthly income, current smoking, alcohol consumption, physical activity, chronic disease status, and energy intake. Notably, this association was exclusively observed in men, and no significant association was observed between the aMED score and AMD in women (adjusted OR = 0.88; 95% CI = 0.61-1.29; p-trend = 0.691).

CONCLUSIONS

This study's findings suggest that a high aMED score may be associated with a reduced risk of AMD in older men. Future studies with larger sample sizes and a prospective or interventional design are required to enhance current understanding regarding the association between diet quality and AMD.

Harnessing the power of longitudinal medical imaging for eye disease prognosis using Transformer-based sequence modeling

Deep learning has enabled breakthroughs in automated diagnosis from medical imaging, with many successful applications in ophthalmology. However, standard medical image classification approaches only assess disease presence at the time of acquisition, neglecting the common clinical setting of longitudinal imaging. For slow, progressive eye diseases like age-related macular degeneration (AMD) and primary open-angle glaucoma (POAG), patients undergo repeated imaging over time to track disease progression and forecasting the future risk of developing a disease is critical to properly plan treatment. Our proposed Longitudinal Transformer for Survival Analysis (LTSA) enables dynamic disease prognosis from longitudinal medical imaging, modeling the time to disease from sequences of fundus photography images captured over long, irregular time periods. Using longitudinal imaging data from the Age-Related Eye Disease Study (AREDS) and Ocular Hypertension Treatment Study (OHTS), LTSA significantly outperformed a single-image baseline in 19/20 head-to-head comparisons on late AMD prognosis and 18/20 comparisons on POAG prognosis. A temporal attention analysis also suggested that, while the most recent image is typically the most influential, prior imaging still provides additional prognostic value.

Correlation between corneal endothelial layer features and age-related macular degeneration severity

PURPOSE

This study aimed to investigate the relationship between corneal endothelial layer features and the severity of age-related macular degeneration (AMD).

METHODS

The study included 119 patients, with 47 females and 72 males. Patients were categorized into four groups based on the AREDS grading system: no AMD (group 1), mild AMD (group 2), moderate AMD (group 3), and advanced AMD (group 4). Only the right eye of patients with both eyes suitable for the study was included. Corneal endothelial cell density (CD), coefficient of variation (CoV), hexagonal cell ratio (HEX), and central corneal thickness (CCT) were measured using specular microscopy (Konan Medical Inc., Nishinomiya, Japan).

RESULTS

Group 1 had 40 patients, group 2 had 27 patients, and groups 3 and 4 had 26 patients each. Significant differences were observed between the mean endothelial CD, CoV, and HEX values among the groups, while no significant difference was found in CCT values (p = 0.049, p = 0.002, p = 0.004, and p = 0.883, respectively). A mild negative correlation was observed between AMD severity and CD and HEX values, while a mild positive correlation was found between AMD severity and CoV.

CONCLUSION

Increasing severity of AMD may negatively impact corneal endothelial layer values.

Harnessing the power of longitudinal medical imaging for eye disease prognosis using Transformer-based sequence modeling

Deep learning has enabled breakthroughs in automated diagnosis from medical imaging, with many successful applications in ophthalmology. However, standard medical image classification approaches only assess disease presence at the time of acquisition, neglecting the common clinical setting of longitudinal imaging. For slow, progressive eye diseases like age-related macular degeneration (AMD) and primary open-angle glaucoma (POAG), patients undergo repeated imaging over time to track disease progression and forecasting the future risk of developing a disease is critical to properly plan treatment. Our proposed Longitudinal Transformer for Survival Analysis (LTSA) enables dynamic disease prognosis from longitudinal medical imaging, modeling the time to disease from sequences of fundus photography images captured over long, irregular time periods. Using longitudinal imaging data from the Age-Related Eye Disease Study (AREDS) and Ocular Hypertension Treatment Study (OHTS), LTSA significantly outperformed a single-image baseline in 19/20 head-to-head comparisons on late AMD prognosis and 18/20 comparisons on POAG prognosis. A temporal attention analysis also suggested that, while the most recent image is typically the most influential, prior imaging still provides additional prognostic value.

91 Circulating inflammatory proteins and the risk of age-related macular degeneration: A bidirectional Mendelian randomization study

Previous observational studies have indicated a correlation between circulating inflammatory proteins and age-related macular degeneration (AMD), yet the causal nature of this relationship remains uncertain. This study aims to investigate the causal link between circulating inflammatory proteins and AMD utilizing a bidirectional two-sample Mendelian randomization approach. The findings indicated that elevated levels of four circulating inflammatory proteins, including C-C Motif Chemokine Ligand 11 (CCL11), Signaling Lymphocytic Activation Molecule Family Member 1 (SLAMF1), TNF Superfamily Member 11 (TRANCE) and Vascular Endothelial Growth Factor A (VEGF-A) lead to the increased risk of AMD, while increased levels of two circulating inflammatory proteins, including Fibroblast Growth Factor 19 (FGF-19) and Interleukin 10 Receptor Subunit Alpha (IL-10RA), resulted in the decreased risk of AMD. Conversely, the results from reverse Mendelian randomization suggested that the presence of AMD lead to the reduction in levels of 15 circulating inflammatory proteins. The findings of this study support the association between elevated levels of circulating inflammatory proteins and the risk of AMD, as well as the potential impact of AMD on reducing circulating inflammatory protein levels. CCL11, SLAMF1, TRANCE and VEGF-A are identified as potential molecular markers in the progression of AMD. These results offer a novel molecular therapeutic target for the prevention and treatment of AMD.

Transcriptomic Analysis Reveals That Excessive Thyroid Hormone Signaling Impairs Phototransduction and Mitochondrial Bioenergetics and Induces Cellular Stress in Mouse Cone Photoreceptors

Thyroid hormone (TH) plays an essential role in cell proliferation, differentiation, and metabolism. Experimental and clinical studies have shown a potential association between TH signaling and retinal degeneration. The suppression of TH signaling protects cone photoreceptors in mouse models of retinal degeneration, whereas excessive TH signaling induces cone degeneration, manifested as reduced light response and a loss of cones. This work investigates the genes/transcriptomic alterations that might be involved in TH-induced cone degeneration in mice using single-cell RNA sequencing (scRNAseq) analysis. One-month-old C57BL/6 mice received triiodothyronine (T3, 20 µg/mL in drinking water) for 4 weeks as a model of hyperthyroidism/excessive TH signaling. At the end of the experiments, retinal cells were dissociated, and cell viability was analyzed before being subjected to scRNAseq. The resulting data were analyzed using the Seurat package and visualized using the Loupe browser. Among 155,866 single cells, we identified 14 cell clusters, representing various retinal cell types, with rod and cone clusters comprising 76% and 4.1% of the total cell population, respectively. Cone cluster transcriptomes demonstrated the most alterations after the T3 treatment, with 450 differentially expressed genes (DEGs), accounting for 38.5% of the total DEGs. Statistically significant changes in the expression of genes in the cone cluster revealed that phototransduction and oxidative phosphorylation were impaired after the T3 treatment, along with mitochondrial dysfunction. A pathway analysis also showed the activation of the sensory neuronal/photoreceptor stress pathways after the T3 treatment. Specifically, the eukaryotic initiation factor-2 signaling pathway and the cAMP response element-binding protein signaling pathway were upregulated. Thus, excessive TH signaling substantially affects cones at the transcriptomic level. The findings from this work provide an insight into how excessive TH signaling induces cone degeneration.

Thyroid Hormone Signaling in Retinal Development and Function: Implications for Diabetic Retinopathy and Age-Related Macular Degeneration

Thyroid Hormones (THs) play a central role in the development, cell growth, differentiation, and metabolic homeostasis of neurosensory systems, including the retina. The coordinated activity of various components of TH signaling, such as TH receptors (THRs) and the TH processing enzymes deiodinases 2 and 3 (DIO2, DIO3), is required for proper retinal maturation and function of the adult photoreceptors, Müller glial cells, and pigmented epithelial cells. Alterations of TH homeostasis, as observed both in frank or subclinical thyroid disorders, have been associated with sight-threatening diseases leading to irreversible vision loss i.e., diabetic retinopathy (DR), and age-related macular degeneration (AMD). Although observational studies do not allow causal inference, emerging data from preclinical models suggest a possible correlation between TH signaling imbalance and the development of retina disease. In this review, we analyze the most important features of TH signaling relevant to retinal development and function and its possible implication in DR and AMD etiology. A better understanding of TH pathways in these pathological settings might help identify novel targets and therapeutic strategies for the prevention and management of retinal disease.

Immunogenetic and Environmental Factors in Age-Related Macular Disease

Age-related macular degeneration (AMD) is a chronic disease, which often develops in older people, but this is not the rule. AMD pathogenesis changes include the anatomical and functional complex. As a result of damage, it occurs, in the retina and macula, among other areas. These changes may lead to partial or total loss of vision. This disease can occur in two clinical forms, i.e., dry (progression is slowly and gradually) and exudative (wet, progression is acute and severe), which usually started as dry form. A coexistence of both forms is possible. AMD etiology is not fully understood. Extensive genetic studies have shown that this disease is multifactorial and that genetic determinants, along with environmental and metabolic-functional factors, are important risk factors. This article reviews the impact of heavy metals, macro- and microelements, and genetic factors on the development of AMD. We present the current state of knowledge about the influence of environmental factors and genetic determinants on the progression of AMD in the confrontation with our own research conducted on the Polish population from Kuyavian-Pomeranian and Lubusz Regions. Our research is concentrated on showing how polluted environments of large agglomerations affects the development of AMD. In addition to confirming heavy metal accumulation, the growth of risk of acute phase factors and polymorphism in the genetic material in AMD development, it will also help in the detection of new markers of this disease. This will lead to a better understanding of the etiology of AMD and will help to establish prevention and early treatment.

The Complement System as a Therapeutic Target in Retinal Disease

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

Sex-Specific Differences in the Relationship Between Prematurity and Ocular Geometry

Purpose

To explore differences in the relationship between gestational age (GA) and birth weight (BW) percentile and ocular geometry between males and females.

Methods

The Gutenberg Prematurity Eye Study involved a prospective ophthalmic examination of adults, aged 18 to 52 years, who were born preterm or at term, in Germany. The associations between GA and BW percentile on the main outcome measures were evaluated by uni- and multivariable linear regression analyses. The main outcome measures were central corneal thickness, corneal radius, anterior chamber depth, lens thickness, posterior segment length, and central foveal thickness. Potential sex-specific differences and an effect modification by sex were analyzed.

Results

This study involved 438 participants (245 females, 193 males) with an average age of 28.6 ± 8.7 years. In female participants, central foveal thickness was negatively associated with a higher GA (B = -2.99; P < 0.001). Similarly, male participants also demonstrated a negative association between central foveal thickness and GA (B = -4.27; P < 0.001). The multivariable model with effect modification revealed that the central foveal thickness was thicker with lower GA. There was an association between the effect modification of GA with sex and central foveal thickness, demonstrating a more pronounced effect of GA on central foveal thickness in male participants (B = 1.29; P = 0.04).

Conclusions

This study identified a sex-specific correlation between lower GA and thicker central foveal thickness, suggesting differences in the developmental trajectory of this biometric parameter concerning GA. A thicker central foveal thickness might affect the visual acuity of individuals born preterm in adulthood, with a more pronounced impact in males and a potential predisposition to age-related diseases later in life. Sex did not influence the association of GA or BW percentile to other ocular geometric parameters.

Association of Genetic Risk for Age-Related Macular Degeneration with Morphological Features of the Retinal Microvascular Network

BACKGROUND

Age-related macular degeneration (AMD) is a multifactorial disease encompassing a complex interaction between aging, environmental risk factors, and genetic susceptibility. The study aimed to determine whether there is a relationship between the polygenic risk score (PRS) in patients with AMD and the characteristics of the retinal vascular network visualized by optical coherence tomography angiography (OCTA).

METHODS

235 patients with AMD and 97 healthy controls were included. We used data from a previous AMD PRS study with the same group. The vascular features from different retina layers were compared between the control group and the patients with AMD. The association between features and PRS was then analyzed using univariate and multivariate approaches.

RESULTS

Significant differences between the control group and AMD patients were found in the vessel diameter distribution (variance: p = 0.0193, skewness: p = 0.0457) and fractal dimension distribution (mean: p = 0.0024, variance: p = 0.0123). Both univariate and multivariate analyses showed no direct and significant association between the characteristics of the vascular network and AMD PRS.

CONCLUSIONS

The vascular features of the retina do not constitute a biomarker of the risk of AMD. We have not identified a genotype-phenotype relationship, and the expression of AMD-related genes is perhaps not associated with the characteristics of the retinal vascular network.

Gender differences in retinal diseases: A review

Gender medicine is a medical specialty that addresses gender differences in health and disease. Traditionally, medical research and clinical practice have often been focused on male subjects and patients. As a result, gender differences in medicine have been overlooked. Gender medicine considers the biological, psychological, and social differences between the genders and how these differences affect the development, diagnosis, treatment, and prevention of disease. For ophthalmological diseases epidemiological differences are known. However, there are not yet any gender-based ophthalmic treatment approaches for women and men. This review provides an overview of gender differences in retinal diseases. It is intended to make ophthalmologists, especially retinologists, more sensitive to the topic of gender medicine. The goal is to enhance comprehension of these aspects by highlighting fundamental gender differences. Integrating gender medicine into ophthalmological practice helps promote personalized and gender-responsive health care and makes medical research more accurate and relevant to the entire population.

Advanced age-related macular degeneration and risk factors in eyes with pachydrusen

The risk of progression to advanced age-related macular degeneration (AMD) varies depending on the type of drusen. This retrospective longitudinal study included 248 eyes of 156 patients with pachydrusen without advanced AMD at baseline. Macular neovascularization (MNV) and geographic atrophy (GA) were evaluated. Risk factors for progression to advanced AMD were determined using multivariate Cox regression analysis. The mean age at baseline was 65.4 ± 9.1 years, and the mean follow-up duration was 6.40 ± 3.58 years. The mean total number of pachydrusen and macular pachydrusen were 4.10 ± 2.85 and 2.27 ± 1.81 per eye, respectively. Pachydrusen was accompanied by other types of drusen in 4.8% (12 eyes) of eyes at baseline. During follow-up, MNVs occurred in 2.8% (seven eyes), including polypoidal choroidal vasculopathy (PCV six eyes); however, no GA occurred. Regarding risk factors for progression to neovascular AMD, age (p = 0.023) and macular pigmentary changes (p = 0.014) were significantly associated with MNV development. The cumulative incidence of MNV was significantly higher in the group with macular pigmentary changes (17.39% vs. 0.57% at 10 years; p = 0.0005). The number of macular pachydrusen and the presence of MNV in the fellow eye did not show a statistically significant relationship with MNV development. Age and macular pigmentary changes are risk factors for MNV development in the eyes with pachydrusen. Eyes with pachydrusen appear to have a risk profile for advanced AMD that is different from that of AMD eyes with drusen or drusenoid deposits other than pachydrusen.

Using the Amsler Grid Test for Age-Related Macular Degeneration Screening

Objectives

To evaluate the use of the Amsler grid test (AGT) in screening for age-related macular degeneration (AMD), one of the most common causes of blindness, in primary healthcare settings.

Materials and Methods

The AGT was applied to 700 eyes of 355 people aged 50 and over who applied to a family health center in Ankara and had no eye complaints. The test was considered positive if the lines on the AGT card were seen as broken or curved, there was a difference in shape or size between the squares, or a color change or blurring was described in any area. An ophthalmologist was consulted if the AGT was positive in one or both eyes. Patients considered suitable by ophthalmologists were evaluated with optical coherence tomography. AGT results were compared with ophthalmologist examination and tomography findings in terms of AMD detection.

Results

The AGT was positive in 97 (13.9%) and negative in 603 (86.1%) out of 700 eyes included in the study. A total of 184 eyes, 79 with a positive AGT and 105 eyes with a negative test, were evaluated by an ophthalmologist. As a result of examinations and tests performed by ophthalmologists, AMD was detected in a total of 67 eyes: 42 of 79 eyes with positive AGT and 25 of 105 eyes with negative AGT but referred to an ophthalmologist for different reasons. In our study, the AGT had 62.7% sensitivity and 68.4% specificity.

Conclusion

The AGT is an inexpensive and easily applicable test. Although moderate sensitivity and specificity were found in our study; further studies are needed to evaluate the suitability of its use for AMD screening in primary care with limited facilities.

Comparison of antiangiogenic agents (ranibizumab, aflibercept, bevacizumab and ziv-aflibercept) in the therapeutic response to the exudative form of age-related macular degeneration according to the treat-and-extend protocol- true head-to-head study

PURPOSE

To evaluate the structural and functional changes in eyes with neovascular age related macular degeneration (nAMD) in a real-world setting, using Treat and Extend protocol (T&E), comparing four antiangiogenic agents.

METHODS

Prospective, observational, case series study performed in 131 patients with the exudative form of nAMD. Patients were randomly assigned into four groups according to the antiangiogenic agent. During the first year, all eyes received at least 3 monthly intravitreal injections of antiangiogenic agents, and afterwards, were submitted to the T&E.

RESULTS

There was statistically significant difference (p < 0.05) between pre- and post-treatment in the best corrected visual acuity measurements by drug used. Patients who used aflibercept had significantly fewer injections than patients using the other drugs (mean = 9.03). No significant difference was observed between the drugs bevacizumab, ranibizumab and ziv-aflibercept. With regard to biomarkers, patients who used aflibercept and had lower baseline central retinal thickness, absence of hyperreflective foci and no subretinal hyperreflective material had the lowest number of injections.

CONCLUSION

Results indicate that over 2 years, Intravitreal aflibercept on T&E provided better visual and anatomical improvements when compared to other drugs used in this study with significantly fewer injections.

Metabolic activity of visceral adipose tissue is associated with age-related macular degeneration: a pilot 18F-FDG PET/CT study

Background

Obesity is known to increase the risk and severity of age-related macular degeneration (AMD). Increased inflamed metabolic activity of visceral adipose tissue (VAT) is considered as a crucial underlying mechanism for the harmful effects of obesity. In this study, we aimed to investigate the inflamed metabolic activity of VAT with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and their association with AMD.

Materials and methods

A total of 57 elderly participants (aged ≥ 50 years) who underwent 18F-FDG PET/CT for health screening and subsequent fundoscopic exam for complaint of recently impaired vision were enrolled. The metabolic activity of VAT was measured from the maximum standardized uptake value (SUVmax) of VAT. The early AMD participant was defined as the participant with either eye satisfying AMD and without any sign of advanced AMD (neovascular AMD or geographic atrophy). The late AMD participant was defined as the participant with either eye satisfying advanced AMD.

Results

VAT SUVmax was highest in participants with late AMD, intermediate in early AMD, and lowest in non-AMD participants. The levels of systemic inflammation surrogate markers were also highest in late AMD group. Furthermore, VAT SUVmax was positively correlated with systemic inflammation surrogate markers and independently associated with the late AMD.

Conclusions

The metabolic activity of VAT evaluated by 18F-FDG PET/CT was associated with the severity of AMD and synchronized with the level of systemic inflammation. Thus, VAT SUVmax could be potentially employed as a surrogate marker of obesity-driven VAT inflammation associated with AMD.

Nighttime Outdoor Artificial Light and Risk of Age-Related Macular Degeneration

Importance

Light pollution's impact on human health is increasingly recognized, but its link to exudative age-related macular degeneration (EAMD) remains unclear.

Objective

To investigate the association between exposure to outdoor artificial light at night (OALAN) and the risk of incident EAMD.

Design, Setting, and Participants

In this nationwide population-based case-control study, all individuals 50 years or older with newly diagnosed EAMD between January 1, 2010, and December 31, 2011, were identified with reference to the Korean National Health Insurance Service registration program database for rare and intractable diseases. Birth year- and sex-matched controls (with no EAMD diagnosis until 2020) were selected at a 1:30 ratio. Data were acquired from May 1 to December 31, 2021, and analyzed from June 1 to November 30, 2022.

Exposures

Mean levels of OALAN at participants' residential addresses during 2008 and 2009 were estimated using time-varying satellite data for a composite view of persistent nighttime illumination at an approximate scale of 1 km2.

Main Outcomes and Measures

The hazard ratios (HRs) and 95% CIs of the association between residential OALAN and risk of incident EAMD were determined based on maximum likelihood estimation after adjusting for sociodemographic characteristics, comorbidities, and area-level risk factors (ie, nighttime traffic noise and particulate matter of aerodynamic diameter ≤10 μm in each participant's administrative district of residence).

Results

A total of 126 418 participants were included in the analysis (mean [SD] age, 66.0 [7.9] years; 78 244 men [61.9%]). Of these, 4078 were patients with newly diagnosed EAMD and 122 340 were EAMD-free matched controls. In fully adjusted models, an IQR (55.8 nW/cm2/sr) increase in OALAN level was associated with an HR of 1.67 (95% CI, 1.56-1.78) for incident EAMD. The exposure-response curve demonstrated a nonlinear, concave upward slope becoming more pronounced at higher levels of light exposure (ie, at approximately 110 nW/cm2/sr). In a subgroup analysis, an IQR increase in OALAN was associated with increased risk of incident EAMD in urban areas (HR, 1.46 [95% CI, 1.33-1.61]) but not in rural areas (HR, 1.01 [95% CI, 0.84-1.22]).

Conclusions and Relevance

In this nationwide population-based case-control study, higher levels of residential OALAN were associated with an increased risk of incident EAMD. Future studies with more detailed information on exposure, individual adaptive behaviors, and potential mediators are warranted.

Causality of Diabetic Nephropathy and Age-Related Macular Degeneration: A Mendelian Randomization Study

PURPOSE

Age-related macular degeneration (AMD) currently stands as the leading cause of irreversible vision loss in the present era. The primary objective of this study was to investigate the causal relationships between diabetic nephropathy (DN), its associated risk factors, and AMD among participants of European descent.

METHODS

Genetic variants associated with DN and its risk factors, encompassing glycemic traits, lipidemic traits, systolic/diastolic blood pressure, obesity, and urate, were obtained from previously published genome-wide association studies. Summary-level statistics for AMD were acquired from the FinnGen database. Univariable and multivariable Mendelian randomization (MR) were employed to conduct this investigation.

RESULTS

Our MR analyses indicated that per 1-standard deviation (SD) increase of DN heightened the risk of overall AMD (p = 1.03 × 10-8, OR = 1.24). And these findings remained consistent when examining both dry AMD (p = 2.27 × 10-4, OR = 1.17) and wet AMD (p = 5.15 × 10-6, OR = 1.33). Additionally, there was a causal association between high-density lipoprotein-cholesterol (HDL-C) levels and an increased risk of AMD (p = 2.69 × 10-3, OR = 1.23), while triglycerides were found to mitigate the risk (p = 0.02, OR = 0.83). Notably, no significant associations were observed between other risk factors of DN and AMD.

CONCLUSIONS

These findings suggest that the impact of DN on the development of AMD may be more substantial than previously believed. Furthermore, elevated HDL-C levels appear to heighten the risk of AMD, whereas triglycerides may provide a protective effect.

Adherence of patients with age-related macular degeneration to AREDS 2-recommended nutritional supplements

BACKGROUND

The Age-Related Eye Disease Study 2 (AREDS 2) proved the benefit of vitamin and mineral supplementation in preventing advanced age-related macular degeneration (AMD). AREDS 2 supplements are indicated for patients with either bilateral intermediate AMD (AREDS category 3) or unilateral neovascular AMD (AREDS category 4).

AIMS

The aims of this telephone survey were to identify the rate of adherence of patients to AREDS 2 supplements and the factors associated with non-compliance in these patient groups.

METHODS

A patient telephone survey was conducted in an Irish tertiary care hospital. Patients were identified by chart review, and their AREDS categorization was reconfirmed. A telephone consultation was conducted with each patient to assess their compliance with the micronutrient supplements.

RESULTS

We identified 120 patients who met the AREDS criteria for supplementation. Of these, 103 patients were graded as category 4, and 17 patients were graded as category 3. Almost a fifth (18%) were current smokers. Under two-thirds (60%) of the patients were taking AREDS 2 supplements. Of the remainder, 83% of patients did not recall being advised of their benefit. The cost was cited by 10% of patients as a reason for non-compliance.

CONCLUSION

The ophthalmologist not only has a duty of care to treat the neovascular complications of AMD, but they must also strive to improve patient compliance with AREDS supplements. The cessation of smoking needs to be actively promoted in order to stop preventable vision loss in patients with AMD.

Alteration in Melanin Content in Retinal Pigment Epithelial Cells upon Hydroquinone Exposure

Abnormal pigmentation or depigmentation of the retinal pigment epithelium (RPE) is a precursor to neovascular age-related macular degeneration (nAMD). In this study, we evaluated the effects of hydroquinone (HQ), the most potent reductant in cigarette smoke, on the melanin production in RPE cells. Induced pluripotent stem cell (iPS)-derived RPE and adult retinal pigment epithelial (ARPE-19) cells were cultured with HQ. Real-time reverse transcription polymerase chain reaction revealed that the expression of melanin-related genes decreased due to the addition of HQ for 1 day. Enzyme-linked immunosorbent immunoassay showed that the concentration of melanin significantly decreased due to the addition of HQ for 24 h. A suspension of RPE cells with HQ for 24 h was prepared, and the absorbance was measured. The absorbance decreased particularly under blue light, suggesting that blue light may reach the choroid and cause choroidal inflammation. Additionally, melanin levels significantly decreased due to the addition of HQ for 1 week. After blue light irradiation on the RPE with HQ for 1 week, the vascular endothelial growth factor in the medium was significantly higher in the HQ group than in the control group. HQ-induced changes in melanin production may be responsible for the uneven pigmentation of the RPE, and these changes may cause nAMD.

Immune System, Inflammation and Autoantigens in Wet Age-Related Macular Degeneration: Pathological Significance and Therapeutic Importance

Wet age-related macular degeneration (wAMD) is a chronic inflammation-associated neurodegenerative disease affecting the posterior part of the eye in the aging population. Aging results in the reduced functionality of cells and tissues, including the cells of the retina. Initiators of a chronic inflammatory and pathologic state in wAMD may be a result of the accumulation of inevitable metabolic injuries associated with the maintenance of tissue homeostasis from a young age to over 50. Apart from this, risk factors like smoking, genetic predisposition, and failure to repair the injuries that occur, alongside attempts to rescue the hypoxic outer retina may also contribute to the pathogenesis. Aging of the immune system (immunosenescence) and a compromised outer blood retinal barrier (BRB) result in the exposure of the privileged milieu of the retina to the systemic immune system, further increasing the severity of the disease. When immune-privileged sites like the retina are under pathological stress, certain age- and disease-related conditions may necessitate assistance from cells distant from the resident ones to help restore the functionality of the tissue. As a necessary part of tissue repair, inflammation is a major response to disease and recruits immune cells to the site of damage. We suspect that the specific reparative inflammatory responses are controlled by an autoantigen-T cell-mediated mechanism, a process that may be hindered in wAMD.

Genetic Risk Assessment of Degenerative Eye Disease (GRADE): study protocol of a prospective assessment of polygenic risk scores to predict diagnosis of glaucoma and age-related macular degeneration

BACKGROUND

Glaucoma and age-related macular degeneration (AMD) account for a substantial portion of global blindness. Both conditions are highly heritable, with recognised monogenic and polygenic inheritance patterns. Current screening guidelines lack decisive recommendations. Polygenic risk scores (PRS) allow for cost-effective broad population risk stratification for these conditions. The predictive potential of PRS could facilitate earlier diagnosis and treatment, and prevent unnecessary vision loss.

METHODS

The Genetic Risk Assessment of Degenerative Eye disease (GRADE) study is a prospective study designed to generate high-quality evidence about the feasibility of PRS to stratify individuals from the general population, enabling identification of those at highest risk of developing glaucoma or AMD. The targeted recruitment is 1000 individuals aged over 50 years, from which blood or saliva samples will be used for genotyping and an individual PRS for glaucoma and AMD will be derived. Individuals with PRS values in the bottom decile (n = 100), top decile (n = 100) and middle 80% (n = 100) for both glaucoma and AMD will undergo a detailed eye examination for glaucoma and/or AMD.

DISCUSSION

The primary objective will be to compare the prevalence of glaucoma and AMD cases between low, intermediate, and high PRS risk groups. We expect to find a higher prevalence of both diseases in the high PRS risk group, as compared to the middle and low risk groups. This prospective study will assess the clinical validity of a PRS for glaucoma and AMD in the general Australian population. Positive findings will support the implementation of PRS into clinical practice.

Geographic Atrophy Management Consensus (GA-MAC): a Delphi panel study on identification, diagnosis and treatment

BACKGROUND/AIMS

With a paradigm shift in geographic atrophy (GA) treatments now available, establishing consensus on the identification and diagnosis of the disease along with considerations for management of patients with GA will assist eye care professionals (ECP) in their day-to-day practices, leading to improved patient outcomes.

METHODS

A modified Delphi panel process (Geographic Atrophy Management Consensus) consisting of three total surveys and one virtual live meeting held between survey 2 and survey 3. Data were collected from July to October 2022. Participants included expert members of the eye care community that have demonstrated outstanding leadership among peers: a steering committee with three ECPs and a 15-member panel divided between five optometrists, five comprehensive ophthalmologists and five retina specialists. Consensus on statements related to the management of patients with GA was calculated using the RAND/UCLA Appropriateness Method.

RESULTS

At the conclusion of the third survey, consensus was reached on 91% of the 77 statements. Critical consensus topics include: (1) optical coherence tomography as the favoured method to diagnose and monitor GA, (2) preferred practice patterns regarding referral of patients to retina specialists and (3) treatment criteria given the advent of emerging therapeutics for GA.

CONCLUSIONS

Generating awareness of early signs of disease development, progression and identifying the best tools to evaluate GA establishes ideal management and referral strategies. Given the paradigm shift in GA management driven by approved therapies, coupled with the fact that the disease is progressive resulting in devastating vision loss, these strategies are critical to ensure best overall outcomes.

Excessive Thyroid Hormone Signaling Induces Photoreceptor Degeneration in Mice

Rod and cone photoreceptors degenerate in inherited and age-related retinal degenerative diseases, ultimately leading to loss of vision. Thyroid hormone (TH) signaling regulates cell proliferation, differentiation, and metabolism. Recent studies have shown a link between TH signaling and retinal degeneration. This work investigates the effects of excessive TH signaling on photoreceptor function and survival in mice. C57BL/6, Thra1 -/-, Thrb2 -/-, Thrb -/-, and the cone dominant Nrl -/- mice received triiodothyronine (T3) treatment (5-20 μg/ml in drinking water) for 30 d, followed by evaluations of retinal function, photoreceptor survival/death, and retinal stress/damage. Treatment with T3 reduced light responses of rods and cones by 50-60%, compared with untreated controls. Outer nuclear layer thickness and cone density were reduced by ∼18% and 75%, respectively, after T3 treatment. Retinal sections prepared from T3-treated mice showed significantly increased numbers of TUNEL-positive, p-γH2AX-positive, and 8-OHdG-positive cells, and activation of Müller glial cells. Gene expression analysis revealed upregulation of the genes involved in oxidative stress, necroptosis, and inflammation after T3 treatment. Deletion of Thra1 prevented T3-induced degeneration of rods but not cones, whereas deletion of Thrb2 preserved both rods and cones. Treatment with an antioxidant partially preserved photoreceptors and reduced retinal stress responses. This study demonstrates that excessive TH signaling induces oxidative stress/damage and necroptosis, induces photoreceptor degeneration, and impairs retinal function. The findings provide insights into the role of TH signaling in retinal degeneration and support the view of targeting TH signaling for photoreceptor protection.

Comparison of Novel Volumetric Microperimetry Metrics in Intermediate Age-Related Macular Degeneration: PINNACLE Study Report 3

Purpose

To investigate and compare novel volumetric microperimetry (MP)-derived metrics in intermediate age-related macular degeneration (iAMD), as current MP metrics show high variability and low sensitivity.

Methods

This is a cross-sectional analysis of microperimetry baseline data from the multicenter, prospective PINNACLE study (ClinicalTrials.gov NCT04269304). The Visual Field Modeling and Analysis (VFMA) software and an open-source implementation (OSI) were applied to calculate MP-derived hill-of-vison (HOV) surface plots and the total volume (VTOT) beneath the plots. Bland-Altman plots were used for methodologic comparison, and the association of retinal sensitivity metrics with explanatory variables was tested with mixed-effects models.

Results

In total, 247 eyes of 189 participants (75 ± 7.3 years) were included in the analysis. The VTOT output of VFMA and OSI exhibited a significant difference (P < 0.0001). VFMA yielded slightly higher coefficients of determination than OSI and mean sensitivity (MS) in univariable and multivariable modeling, for example, in association with low-luminance visual acuity (LLVA) (marginal R2/conditional R2: VFMA 0.171/0.771, OSI 0.162/0.765, MS 0.133/0.755). In the multivariable analysis, LLVA was the only demonstrable predictor of VFMA VTOT (t-value, P-value: -7.5, <0.001) and MS (-6.5, <0.001).

Conclusions

The HOV-derived metric of VTOT exhibits favorable characteristics compared to MS in evaluating retinal sensitivity. The output of VFMA and OSI is not exactly interchangeable in this cross-sectional analysis. Longitudinal analysis is necessary to assess their performance in ability-to-detect change.

Translational Relevance

This study explores new volumetric MP endpoints for future application in therapeutic trials in iAMD and reports specific characteristics of the available HOV software applications.

Discontinuation of treatment and retreatment of neovascular age-related macular degeneration in the real-world: Bundang AMD cohort study report 5

Introduction

This single-center retrospective cohort study investigated the incidence rate and risk factors for the discontinuation of anti-vascular endothelial growth factor (VEGF) injections and retreatment in typical neovascular age-related macular degeneration (tnAMD) and polypoidal choroidal vasculopathy (PCV) in the real-world setting.

Methods

A total of 488 eyes with either tnAMD (n = 334) or PCV (n = 154) followed up for ≥3 years were analyzed. The discontinuation of treatment was defined as the cessation of anti-VEGF injections for 1 year or longer. Eyes with discontinuing treatment were subdivided into group A: eyes with stable responses (complete or incomplete resolution) and group B: those with no expectation of visual gain or poor response. The proportion and median time of discontinuation of treatment or retreatment were analyzed. The visual prognosis and the associated risk factors for the discontinuation of treatment or retreatment were also investigated.

Results

The mean follow-up period was 8.1 ± 3.4 years. Of 488 eyes, discontinuation of the treatment occurred in 322 eyes (66.0%), and the median time to discontinuation was 1.5 years after the initial injection. Of 297 eyes with discontinuation of treatment excluding 25 eyes with vitrectomy or photodynamic therapy after the discontinuation of the injection, 277 eyes belonged to group A and the remaining 20 eyes belonged to group B. Of the 277 eyes discontinuing treatment with a stable response, 185 eyes (66.8%) were given retreatment. The median time to retreatment was 3.3 years after the discontinuation of the injections. PCV and the lower annual number of injections were the significant factors associated with discontinuation. Younger age, male gender, and PCV were the significant factors for the retreatment.

Conclusion

Our long-term real-world study showed that two-thirds of eyes with neovascular age-related macular degeneration (nAMD) had the discontinuation of the anti-VEGF injections and two-thirds of eyes discontinuing treatment with stable responses experienced retreatment. Long-term follow-up and regular monitoring are needed to detect the recurrence.

TFOS Lifestyle: Impact of nutrition on the ocular surface

Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials.

Red Wine Extract Prevents Oxidative Stress and Inflammation in ARPE-19 Retinal Cells

Age-related macular degeneration (AMD) is one of the most commonly occurring ocular diseases worldwide. This degenerative condition affects the retina and leads to the loss of central vision. The current treatments are focused on the late stage of the disease, but recent studies have highlighted the importance and benefits of preventive treatments and how good dietary habits can reduce the risk of progression to an advanced form of the disease. In this context, we studied whether resveratrol (RSV) or a polyphenolic cocktail, red wine extract (RWE), are able to prevent the initiating events of AMD (i.e., oxidative stress and inflammation) in human ARPE-19 retinal pigment epithelial (RPE) cells and macrophages. This study highlights that RWE and RSV can prevent hydrogen peroxide (H₂O₂) or 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH)-induced oxidative stress and can subsequently prevent DNA damage via the inhibition of the ATM (ataxia telangiectasia-mutated)/Chk2 (checkpoint kinase 2) or Chk1 signaling pathways, respectively. Moreover, ELISA assays show that RWE and RSV can prevent the secretion of proinflammatory cytokines in RPE cells and in human macrophages. Interestingly, RWE exhibits a greater protective impact compared to RSV alone, even though RSV was more concentrated when used alone than in the red wine extract. Our results suggest that RWE and RSV may have potential interest as preventive nutritional supplementations against AMD.

Role of Complement in the Onset of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a progressive degenerative disease of the central retina and the leading cause of severe loss of central vision in people over age 50. Patients gradually lose central visual acuity, compromising their ability to read, write, drive, and recognize faces, all of which greatly impact daily life activities. Quality of life is significantly affected in these patients, and there are worse levels of depression as a result. AMD is a complex, multifactorial disease in which age and genetics, as well as environmental factors, all play a role in its development and progression. The mechanism by which these risk factors interact and converge towards AMD are not fully understood, and therefore, drug discovery is challenging, with no successful therapeutic attempt to prevent the development of this disease. In this review, we describe the pathophysiology of AMD and review the role of complement, which is a major risk factor in the development of AMD.

Trends and disparities in disease burden of age-related macular degeneration from 1990 to 2019: Results from the global burden of disease study 2019

Objectives

This study aims to estimate the trends and disparities in the worldwide burden for health of AMD, overall and by age, sex, socio-demographic index (SDI), region, and nation using prevalence and years lived with disability (YLDs) from Global Burden of Disease (GBD) study 2019.

Methods

This retrospective study presents the prevalent AMD cases and YLDs from 1990-2019, as well as the age-standardized prevalence rate (ASPR) and age-standardized YLD rate (ASYR) of AMD. To measure changes over time, estimated annual percentage changes (EAPCs) of the age-standardized rates (ASRs) were analyzed globally, then studied further by sex, SDI, region, and nation. We included data from the 2019 Global Burden of Disease (GBD) database to examine AMD prevalence and YLDs from 1990-2019 in 204 countries and territories, as well as demographic information such as age, sex, SDI, region, and nation.

Results

Globally, the number of prevalent AMD cases increased from 3,581,329.17 (95% uncertainty interval [UI], 3,025,619.4-4,188,835.7) in 1990 to 7,792,530 (95% UI, 6,526,081.5-9,159,394.9) in 2019, and the number of YLDs increased from 296,771.93 (95% uncertainty interval [UI], 205,462.8-418,699.82) in 1990 to 564,055.1 (95% UI, 392,930.7-789,194.64) in 2019. The ASPR of AMD had a decreased trend with an EAPC of -0.15 (95% confidence interval [CI], -0.2 to -0.11) from 1990 to 2019, and the ASYR of AMD showed a decreased trend with an EAPC of -0.71 (95% confidence interval [CI], -0.78 to -0.65) during this period. The prevalence and YLDs of AMD in adults over 50 years of age showed a significant increase. The prevalence and YLDs of AMD were significantly higher in females than males, overall. The ASPRs and ASYRs in low SDI regions was greater than in high SDI regions from 1990 to 2019. In addition, increases in prevalence and YLDs differed by regions and nations, as well as level of socio-economic development.

Conclusion

The number of prevalent cases and YLDs due to AMD increased over 30 years and were directly linked to age, sex, socio-economic status, and geographic location. These findings can not only guide public health work but also provide an epidemiological basis for global strategy formulation regarding this global health challenge.

Influence of Clinical and Genetic Factors on the Progression of Age-Related Macular Degeneration: A 3-Year Follow-Up

The aim of the present study was to analyze the relationship of age-related macular degeneration (AMD) progression with clinical characteristics, demographic, and environmental risk factors that would affect disease development. In addition, the influence of three genetic AMD polymorphisms (CFH Y402H, ARMS2 A69S, and PRPH2 c.582-67T>A) on AMD progression was investigated. In total, 94 participants with previously diagnosed early or intermediate AMD in at least one eye were recalled for an updated re-evaluation after 3 years. The initial visual outcomes, medical history, retinal imaging data, and choroidal imaging data were collected to characterize the AMD disease status. Among the AMD patients, 48 demonstrated AMD progression, and 46 showed no disease worsening at 3 years. Disease progression was significantly associated with worse initial visual acuity (OR = 6.74, 95% CI = 1.24-36.79, p = 0.03) and the presence of the wet AMD subtype in fellow eyes (OR = 3.79, 95%CI = 0.94-15.2, p = 0.05). In addition, a higher risk of AMD progression appeared in the patients with active thyroxine supplementation (OR = 4.77, CI = 1.25-18.25, p = 0.002). The CC variant of CFH Y402H was associated with AMD advancement compared to the TC+TT phenotype (OR = 2.76, 95% CI: 0.98-7.79, p = 0.05). Identifying risk factors of AMD progression may lead to earlier intervention and better outcomes, preventing the expansion of the late stage of the disease.

Nutrition-induced macular-degeneration-like photoreceptor damage in jumping spider eyes

Age-related macular degeneration (AMD) is a leading cause of vision loss in humans. Despite its prevalence and medical significance, many aspects of AMD remain elusive and treatment options are limited. Here, we present data that suggest jumping spiders offer a unique opportunity for understanding the fundamentals underlying retinal degeneration, thereby shedding light on a process that impacts millions of people globally. Using a micro-ophthalmoscope and histological evidence, we demonstrate that significant photoreceptor damage can occur during development in the image-forming anterior lateral eyes of the jumping spider Phidippus audax. Furthermore, we find that this photoreceptor degeneration is exacerbated by inadequate nutrition and is most prevalent in the high-density region of the retina, like AMD in humans. This suggests that similar to those in vertebrates, the retinas in P. audax are challenged to meet high-energy cellular demands.

Is preventable sight loss truly preventable? An exploration of a public health indicator for sight loss due to age-related macular degeneration in England

BACKGROUND

Age-related macular degeneration accounts for the majority of severe sight impairment and sight impairment registration and certifications in adults in the UK [1, 2]. Whilst these treatments are effective in arresting nAMD progression, there is currently no treatment for GA [1, 3, 4].

METHODS

This paper provides an update to the data collected by Bunce et al. [3] and details the number of people certified together with incidence rates for the various types of AMD by: sex, sight impairment status, and for all ages using the 2016/2017 and 2017/2018 CVI due to AMD data for England from the Moorfields Eye Hospital, supplemented with 2017-2018 PHOF indicator 4.12i/E12a data. The study population includes individuals of all ages in England who were newly certified with visual impairment due to AMD.

RESULTS

Between 2016 and 2017, CVIs due to AMD totalled to 11,215; between 2017 and 2018, CVIs due to AMD totalled to 10,914. The PHOF indicator 4.12i/E12a assessed showed that overall rates of AMD certifications have steadily declined in England from 131.5 per 100,000 in 2010/2011 to 106.7 per 100,000 in 2017/2018.

CONCLUSION

As treatment is available for nAMD, a reduction in nAMD certifications could be expected; however, growth of the elderly population in England combined with there currently being no treatment available for GA means AMD certification rates should be increasing. Therefore, it is postulated that not all cases of AMD are being certified and registered with some likely going undiagnosed.