Purpose:The purpose of this study is to identify associative factors of vision threatening complications of diabetic retinopathy (DR), including proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME) in a New Mexican patient population with Type 2 diabetes featuring a high proportion of Hispanic and American Indian patients. Methods:In a retrospective, case-control, cross-sectional study, we performed both univariate and multivariate logistic regression testing of systemic factors for association among patients with nonproliferative diabetic retinopathy (NPDR) without DME, NPDR with DME, and PDR. We also used receiver operating characteristic (ROC) curves to understand how reliable glycemic control is at predicting DR end-complications. Results:Among our 584 patients, 172 were diagnosed with NPDR without DME, 293 with PDR, and 119 with NPDR with DME. A total of 25% of patients with NPDR without DME had poor glycemic control (HbA1c levels of ≥ 9.0%). Similarly, 10% of PDR and 7% of NPDR with DME patients had good glycemic control (HbA1c levels ≤ 7.0%), despite their advanced eye disease. For patients with PDR, we identified significant independent associations with microalbuminuria and macroalbuminuria, Hispanic ethnicity, duration of diabetes, and the use of insulin and beta-blocker medications. In NPDR with DME patients, significant associations were noted with microalbuminuria and macroalbuminuria, HbA1c, GFR, and beta-blocker medications. The hemoglobin A1c level was not significantly associated with PDR but was significantly associated with NPDR with DME. The ROC curve analysis indicated poor predictability for the HbA1c model concerning the presence of PDR (AUC = 0.640) and NPDR with DME (AUC = 0.640). Conclusions:This study suggests that glycemic exposure alone is not a good enough predictor of DR progression. Other diabetic microvascular complications such as nephropathy, in addition to race/ethnicity with differing genetic associative factors, may also play a role in the multifactorial progression through DR phenotypes.

Introduction and Objective: Diabetic retinopathy (DR) exhibits pronounced phenotypic heterogeneity, with most affected cases developing either proliferative diabetic retinopathy (PDR) or diabetic macular edema (DME), while others remain protected to advanced DR despite long duration of diabetes. This divergence suggests genetic modifiers influence susceptibility or protection. We aimed to identify genetic variants and pathways driving progression to PDR, DME, or long-term protection against advanced DR. Methods: We applied extreme phenotype genomic approaches in deeply phenotyped cohorts with isolated PDR, isolated DME, or long-duration diabetes (>20 years) with minimal or no DR. DR severity was graded on ultrawide-field images using ETDRS criteria by masked readers. Whole-exome or whole-genome sequencing was followed by stringent quality control, rare-variant filtering, burden testing, gene-level aggregation, exome-wide association, SKAT analyses, and pathway and network annotation. Results: Distinct rare-variant architectures characterized PDR and DME. PDR showed a higher burden of predicted high-impact variants enriched in immune, inflammatory, metabolic, and angiogenic pathways. In contrast, DME-associated and DR-protective variants were enriched in pathways related to vascular barrier integrity, sensory signaling, and anti-inflammatory or antiproliferative processes. Protective variants were enriched in the No DR cohort, particularly in genes involved in innate immunity and cellular stress responses (TLR5, RNASEL, STIM1, EDA2R, OSBPL1A), concordant with reduced systemic cytokine levels. Despite phenotypic differences, a shared core of inflammation associated genes emerged, indicating a convergent inflammatory state shaped by phenotype specific rare variants. Conclusion: Our study indicate that functional genetic variation modulates DR outcomes, distinguishing progression to PDR or DME and DR progression. These phenotype-specific biomarkers facilitate precise risk stratification and the development of targeted interventions. Disclosure S. Rangasamy: None. C. Legendre: None. J. Don: None. D. Subramani: None. F. Monickaraj: None. N. Schork: None. D. Duggan: None. J. Sun: Research Support; Current; Adaptive Sensory Technology. Other - Research support and food at meeting; Current; Boehringer Ingelheim International GmbH. Research Support; Current; Roche Pharmaceuticals. Research Support; Ended; Genentech, Inc. Research Support; Current; LKC Technologies, Konan. Other - Research support and food at meeting; Current; Novo Nordisk. Research Support; Current; Optovue, Incorporated. Research Support; Ended; Physical Sciences, Inc. Other - Food at meeting; Ended; Alcon. L.P. Aiello: Advisory Panel; Current; Optos plc. Research Support; Current; Boehringer Ingelheim International GmbH. Consultant; Current; Ceramedix. A. Das: None. Funding NIH 1R01EY028606

β-thalassemia patients often experience ocular abnormalities such as angioid streaks (ASs), retinal pigmented epithelium degradation, visual field defects, and in rare instances choroidal neovascularization (CNV). Although ASs are common in individuals with hemoglobinopathies, the occurrence of choroidal neovascularization without preceding ASs is exceptionally rare. In this report, we describe a β-thalassemia patient who had developed CNV at the age of 27 years and also had experience of renal stones at the age of 19 years. He had undergone splenectomy and was under conservative therapy of iron supplementation. We conducted whole-exome sequencing (WES) in search of CNV-associated variants. Through variant filtering and Phenolyzer analysis, we have identified a rare heterozygous missense variant in the ABCC6 gene, ABCC6:NM_001171:exon25:c.3524T>C (rs376062004). In silico analysis revealed that this variant is present in the highly conserved region and is likely to decrease the stability of the protein. Mutation in the ABCC6 gene leads to pseudoxanthoma elasticum (PXE). Previously, it was believed that ASs and subsequent CNV-like ocular complication may develop due to the pathophysiological condition of thalassemia. However, our study provides compelling evidence that rare mutations in the ABCC6 gene, in combination with oxygen insufficiency, may contribute to the development of CNV in β-thalassemia patients. This finding highlights the potential genetic basis of PXE-mediated CNV development in β-thalassemia.

BackgroundAlthough diabetic retinopathy (DR) and diabetic nephropathy (DN) are well known microvascular complications of diabetes, the correlation between DR and DN remains uncertain. Several studies have suggested differences in etiology and risk factors between these two complications.ObjectivesTo examine whether diabetic retinopathy (DR) and nephropathy (DN) have significant concordance in terms of severity progression in patients with type 2 diabetes.MethodsA case-control study was conducted involving two cohorts of type 2 diabetic patients from a New Mexican population. The cases had confirmed end-stage renal disease (ESRD; Stage 5, on dialysis, eGFR < 15 mL/min, n = 164), while the controls had mild diabetic nephropathy (DN) (Stage 1 or Stage 2, eGFR > 60 mL/min, n = 165). Systemic parameters were collected through retrospective chart reviews, which included HbA1c, blood pressure (BP), lipid levels, serum creatinine (Cr), and retinopathy status determined by dilated fundus examinations. Statistical analyses were conducted, encompassing univariate and multivariate logistic regression analyses for continuous variables, as well as a Chi-squared test for categorical variables.ResultsThe majority (65%) of the ESRD cohort had proliferative diabetic retinopathy (PDR), while 18% of patients exhibited no diabetic retinopathy (DR) or mild non-proliferative diabetic retinopathy (NPDR). Conversely, approximately 38% of the mild DN cohort had PDR. In the univariate analysis, ESRD was significantly associated with lower HbA1c levels (p<0.0001) and higher systolic blood pressure (p<0.0001). Within the ESRD cohort, the onset of PDR was significantly linked to younger age (p=0.0002), higher diastolic blood pressure (p=0.0319), and elevated LDL (p=0.0361). In the multivariate analysis, the development of PDR was inversely related to age (p=0.001, OR=0.95) and positively correlated with serum creatinine (p<0.0001, OR=1.25), systolic blood pressure (p=0.0221, OR=1.023), and albuminuria (p=0.0006, OR=4.65). HbA1c levels showed no significant correlation with the progression of PDR. The use of PDR as a screening tool for chronic kidney disease (CKD) has a sensitivity of 78.68% and a specificity of 51.16%, indicating that it is a suboptimal screening method.ConclusionsOur findings suggest discordance between the progression of diabetic retinopathy and nephropathy.

The Mary Tyler Moore Vision Initiative (MTM Vision) Diabetic Retinal Disease (DRD) Clinical Endpoints Workshop was held on November 14, 2023. More than 130 clinicians, scientists, and representatives from funding and regulatory agencies, diagnostic, therapeutic, and biotech industry and patient advocates discussed the needs for new diagnostic and therapeutic approaches to preserve and restore retinal neurovascular unit integrity in people with diabetes. MTM Vision projects, notably updating the DRD staging system and severity scale, establishing a human ocular biorepository and resource, and validating useful clinical endpoints and biomarkers to accelerate development of new drugs and improve patient care were emphasized. A public-private consortium is essential to fulfill the objectives of MTM Vision for the benefit of persons with diabetes.

OBJECTIVE To investigate quantitative and qualitative changes in retinal structure using optical coherence tomography (OCT) and their associations with systemic or other risk factors in individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS In the Epidemiology of Diabetes Interventions and Complications study, OCT images were obtained during study years 25–28 (2019-2022) in 937 participants; 54% and 46% were from the original intensive (INT) and conventional (CONV) treatment groups, respectively. RESULTS Participants were on average 61 years old with diabetes duration of 39 years and HbA1c 7.6%. Participants originally in the CONV group were more likely to have disorganization of retinal inner layers (DRIL) (CONV: 27.3% vs INT: 18.7%; P=0.0003), intraretinal fluid (CONV 24.4% vs INT 19.2%; P=0.0222), and intraretinal cysts (CONV 20.8% vs INT 16.6%; P=0.0471). In multivariable models, sex, age, smoking, mean updated SBP, and history of CSME and of anti-VEGF treatment were independently associated with changes in central subfield thickness, while HbA1c, BMI, history of CSME and of ocular surgery were associated with DRIL. Visual acuity decline was associated with significant thinning of all retinal subfields except for the central and inner nasal subfields. CONCLUSIONS Early intensive glycemic management in type 1 diabetes is associated with a decreased risk of DRIL. This important morphological abnormality was associated with a history of macular edema, a history of ocular surgery and worse visual acuity. This study reveals benefits of intensive glycemic management on the retina beyond features detected by fundus photographs and ophthalmoscopy.

Purpose: Hyperglycemia is a major risk factor for early lesions of diabetic retinal disease (DRD). Updating the DRD staging system to incorporate relevant basic and cellular mechanisms pertinent to DRD is necessary to better address early disease, disease progression, the use of therapeutic interventions, and treatment effectiveness. Design: We sought to review preclinical and clinical evidence on basic and cellular mechanisms potentially pertinent to DRD that might eventually be relevant to update the DRD staging system. Participants: Not applicable. Methods: The Basic and Cellular Mechanisms Working Group (BCM-WG) of the Mary Tyler Moore Vision Initiative carefully and extensively reviewed available preclinical and clinical evidence through multiple iterations and classified these. Main Outcome Measures: Classification was made into evidence grids, level of supporting evidence, and anticipated future relevance to DRD. Results: A total of 40 identified targets based on pathophysiology and other parameters for DRD were grouped into concepts or evaluated as specific candidates. VEGFA, peroxisome proliferator-activated receptor- alpha related pathways, plasma kallikrein, and angiopoietin 2 had strong agreement as promising for use as biomarkers in diagnostic, monitoring, predictive, prognostic, and pharmacodynamic responses as well as for susceptibility/risk biomarkers that could underlie new assessments and eventually be considered within an updated DRD staging system or treatment, based on the evidence and need for research that would fit within a 2year timeline. The BCM-WG found there was strong reason also to pursue the following important concepts regarding scientific research of DRD acknowledging their regulation by hyperglycemia: inflammatory/cytokines, oxidative signaling, vasoprotection, neuroprotection, mitophagy, and nutrients/microbiome. Conclusion: Promising targets that might eventually be considered within an updated DRD staging system or treatment were identified. Although the BCM-WG recognizes that at this stage little can be incorporated into a new DRD staging system, numerous potential targets and important concepts deserve continued support and research, as they may eventually serve as biomarkers and/or therapeutic targets with measurable benefits to patients with diabetes. Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. Ophthalmology Science 2024;4:100521 (c) 2024 by the American Academy of Ophthalmology. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/). Supplemental material available at www.ophthalmologyscience.org.

Purpose: Retinal fibrosis, characterized by fibroblasts, myofibroblasts, and extracellular matrix formation, occurs on the surface of the retinas following retinal neovascularization and vitreous hemorrhage. We have previously shown the contribution of neutrophils in the blood-retinal barrier alteration in an animal model of diabetic retinopathy (DR). We evaluated the hypothesis that the neutrophil signaling pathway contributes to the development of retinal fibrosis in DR. Methods: Neutrophil extracellular traps (NETs) were prepared by treating human neutrophils with 25 mM glucose and 250ug advanced glycation endproducts. Transendothelial resistance of NETs and disulfiram (NET inhibitor) in human retinal endothelial cells was measured by electric cell-substrate Impedance Sensing (ECIS). The mRNA and protein expression of NETs, fibrosis, and endothelial mesenchymal transition (EndoMT) markers were analyzed on Streptozotocin-induced diabetic mice (3 months). NETs marker (Citrullinated Histone H3) was measured on serum samples of diabetic and nondiabetic subjects (n=10 in each group). Results: Endothelial monolayer permeability was increased by NETs and significantly reduced by 10μM disulfiram. mRNA expression of EndoMT markers (TGFb1, MMP2, MMP9, ICAM1, VCAM1, & VE-Cad) and protein expression of NETs markers (PAD4 & Cit H3) were significantly increased in the retinas of diabetic animals compared with nondiabetic. Serum levels of Cit H3 were significantly increased in diabetic compared with nondiabetic subjects. Conclusions: Overall, we have shown evidence that neutrophil extracellular traps triggered by neutrophil infiltration in diabetes play an essential role in EndoMT process and fibrosis. Targeting the NETs may be a potential therapeutic approach to preventing retinal fibrosis formation and traction retinal detachment. Disclosure F. Monickaraj: None. A. Das: None. J. Smoake: None. Funding NIH 5R01EY0286061I01BX005348-01A1

Introduction & Objective: Our prior research has shown a clear distinction between two types of diabetic retinopathy (DR): predominantly exudative diabetic macular edema (DME) and predominantly proliferative diabetic retinopathy (PDR). These clinical presentations often occur separately, with a large percentage of patients (85% for PDR, 80% for DME) not showing signs of the other type. This suggests that DME and PDR may not be a single disease entity that progresses linearly but rather distinct diseases driven by different molecular mechanisms and genetic factors. Methods: We analyzed two distinct patient groups: i) only PDR and no signs of DME (n=182), and the other with only center-involving DME and no PDR (n =77). The severity of PDR was graded using the ETDRS standard protocol on ultrawide field retinal images. Whole-exome and whole-genome sequencing were performed to identify genetic factors, and a novel algorithm was used to evaluate the impact of coding variants in the cohort. Results: Comparative analysis of patients with exclusive manifestations of PDR compared to DME revealed a unique genetic framework differentiating the two cohorts. Notably, the prevalence of rare functional variants was significantly elevated in the PDR group (p<0.05). We discovered functional variants in genes, including CD36, MMRN2, EPHB2, PLAUR, and RAPGEF3, which are enriched in the angiogenesis pathway. Phenotype-centric gene variant analysis underscored the role of MMRN2, a key player in angiogenesis (p<0.001). MMRN2 (Multimerin-2) is a crucial regulator of endothelial cell movement, functioning as a negative modulator of angiogenesis by inhibiting KDR activation through its interaction with VEGFA. Conclusions: Rare functional variants may act as phenotype modifiers, potentially modulating the trajectory of DR into DME or PDR. Functional validation of these factors could represent new biomarkers and therapeutic targets for DR. Disclosure S. Rangasamy: None. F. Monickaraj: None. J.K. Sun: Research Support; Optovue, Boehringer-Ingelheim, Novo Nordisk, Roche Pharmaceuticals. Other Relationship; Roche Pharmaceuticals. Research Support; Physical Sciences, Inc, Boston Micromachines. L.P. Aiello: Advisory Panel; Novo Nordisk. Stock/Shareholder; Kalvista. Other Relationship; Optos. Consultant; Ceramedix. A. Das: None. Funding 5R01EY028606

Inflammation plays an important role in the pathogenesis of diabetic retinopathy (DR). To precisely define the inflammatory mediators, we examined the transcriptomic profile of human retinal endothelial cells exposed to advanced glycation end products, which revealed the neutrophil chemoattractant chemokine CXCL1 as one of the top genes upregulated. The effect of neutrophils in the alteration of the blood-retinal barrier (BRB) was further assessed in wild-type C57BL/6J mice intravitreally injected with recombinant CXCL1 as well as in streptozotocin-induced diabetic mice. Both intravitreally CXCL1-injected and diabetic animals showed significantly increased retinal vascular permeability, with significant increase in infiltration of neutrophils and monocytes in retinas and increased expression of chemokines and their receptors, proteases, and adhesion molecules. Treatment with Ly6G antibody for neutrophil depletion in both diabetic mice as well as CXCL1-injected animals showed significantly decreased retinal vascular permeability accompanied by decreased infiltration of neutrophils and monocytes and decreased expression of cytokines and proteases. CXCL1 level was significantly increased in the serum samples of patients with DR compared with samples of those without diabetes. These data reveal a novel mechanism by which the chemokine CXCL1, through neutrophil recruitment, alters the BRB in DR and, thus, serves as a potential novel therapeutic target. Article Highlights Intravitreal CXCL1 injection and diabetes result in increased retinal vascular permeability with neutrophil and monocyte recruitment. Ly6G antibody treatment for neutrophil depletion in both animal models showed decreased retinal permeability and decreased cytokine expression. CXCL1 is produced by retinal endothelial cells, pericytes, and astrocytes. CXCL1 level is significantly increased in serum samples of patients with diabetic retinopathy. CXCL1, through neutrophil recruitment, alters the blood-retinal barrier in diabetic retinopathy and, thus, may be used as a therapeutic target.

OBJECTIVE:To determine whether individuals with type 1 diabetes (T1D) who develop any retinopathy at any time prior to 5 years of diabetes duration have an increased subsequent risk for further progression of retinopathy or onset of proliferative diabetic retinopathy (PDR), clinically significant macular edema (CSME), diabetes-related retinal photocoagulation, or anti-vascular endothelial growth factor injections. Additionally, to determine the influence of HbA1c and other risk factors in these individuals. RESEARCH DESIGN AND METHODS:Diabetic retinopathy (DR) was assessed longitudinally using standardized stereoscopic seven-field fundus photography at time intervals of 6 months to 4 years. Early-onset DR (EDR) was defined as onset prior to 5 years of T1D duration. Cox models assessed the associations of EDR with subsequent risk of outcomes. RESULTS:In unadjusted models, individuals with EDR (n = 484) had an increased subsequent risk of PDR (hazard ratio [HR] 1.51 [95% CI 1.12, 2.02], P = 0.006), CSME (HR 1.44 [1.10, 1.88], P = 0.008), and diabetes-related retinal photocoagulation (HR 1.48 [1.12, 1.96], P = 0.006) compared with individuals without EDR (n = 369). These associations remained significant when adjusted for HbA1c, but only the association with PDR remained significant after adjustment for age, duration of T1D, HbA1c, sex, systolic/diastolic blood pressure, pulse, use of ACE inhibitors, albumin excretion rate, and estimated glomerular filtration rate (HR 1.47 [95% CI 1.04, 2.06], P = 0.028). CONCLUSIONS:These data suggest that individuals with any sign of retinopathy within the first 5 years of T1D onset may be at higher risk of long-term development of advanced DR, especially PDR. Identification of early-onset DR may influence prognosis and help guide therapeutic management to reduce the risk of future visual loss in these individuals.