Diabetic retinopathy and diabetic macular edema: pathophysiology, screening, and novel therapies

Topical delivery of anti-VEGF macromolecules for retinopathy: A review

Retinopathy is a sight-threatening posterior eye disease involving microvascular complications. Diabetic retinopathy (DR) is the most prevalent form of this. Topical biologics (anti-VEGFs) have better therapeutic outcomes compared to steroids because of minimum adverse effects. However, only invasive methods have been approved, which are associated with serious issues related to patient compliance. Non-invasive administrations of anti-VEGFs have challenges, including stability and penetrability. Investigations on the use of cell-penetrating peptides as carriers for the delivery of biologics have shown encouraging results. Loading the polar biologics into the core of liposomes to capitalize on the lipidic nature and small size for retinal access has also received research attention. However, issues related to the controlled release of these topical biologics for continued retinal access need further attention. Despite the challenges of achieving controlled release in topical application of ocular biologics, there is scope to develop their gels or solid scaffolds. Targeting by capitalizing on membrane transporters of endogenous substances and nutrients has succeeded in brain and other tissue-specific delivery. Thus, there is scope to improve penetrability using a membrane transportation system, as the eye has diverse kinds of membrane transporters that uptake nutrients and endogenous substances.

Applications of generative adversarial networks in the diagnosis, prognosis, and treatment of ophthalmic diseases

PURPOSE

Generative adversarial networks (GANs) are key components of many artificial intelligence (AI) systems that are applied to image-informed bioengineering and medicine. GANs combat key limitations facing deep learning models: small, unbalanced datasets containing few images of severe disease. The predictive capacity of conditional GANs may also be extremely useful in managing disease on an individual basis. This narrative review focusses on the application of GANs in ophthalmology, in order to provide a critical account of the current state and ongoing challenges for healthcare professionals and allied scientists who are interested in this rapidly evolving field.

METHODS

We performed a search of studies that apply generative adversarial networks (GANs) in diagnosis, therapy and prognosis of eight eye diseases. These disparate tasks were selected to highlight developments in GAN techniques, differences and common features to aid practitioners and future adopters in the field of ophthalmology.

RESULTS

The studies we identified show that GANs have demonstrated capacity to: generate realistic and useful synthetic images, convert image modality, improve image quality, enhance extraction of relevant features, and provide prognostic predictions based on input images and other relevant data.

CONCLUSION

The broad range of architectures considered describe how GAN technology is evolving to meet different challenges (including segmentation and multi-modal imaging) that are of particular relevance to ophthalmology. The wide availability of datasets now facilitates the entry of new researchers to the field. However mainstream adoption of GAN technology for clinical use remains contingent on larger public datasets for widespread validation and necessary regulatory oversight.

Increased fatty acid-binding protein 4 levels are associated with the risk of developing retinopathy in type 2 diabetes mellitus patients

AIM

Fatty acid-binding protein 4 (FABP4) is associated with the risk of developing diabetes and its microvascular complications. We aimed to explore the association between serum FABP4 levels and the risk of diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM).

METHODS

Serum FABP4 levels were measured via enzyme-linked immunosorbent assay in 275 individuals (78 healthy controls, 197 T2DM patients). DR severity was determined via fundus fluorescence angiography. Multivariate analyses were performed via logistic regression models. The diagnostic value of these measures was assessed via receiver operating characteristic curve analysis.

RESULTS

Serum FABP4 levels were significantly greater in the proliferative DR (PDR) group than in the ZeroDR (ZDR) and non-proliferative DR (NPDR) groups, and the FABP4 levels positively with DR severity (r = 0.328, P < 0.001). Logistic regression analysis revealed that after adjusting for potential confounders, increased FABP4, fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) levels were risk factors for DR development, and FABP4 was an independent risk factor for PDR development. A multivariate logistic regression model that included FABP4 as a categorical binary variable with a cutoff value of 20.57 ng/ml revealed that a level of FABP4 above the cutoff value increased the DR risk (OR=6.394; 95 % CI=3.18;13.58; P < 0.001). Similarly, a FABP4 concentration above the cutoff value of 24.40 ng/ml increased the PDR risk (OR=4.686; 95 % CI=1.907;12.34; P = 0.001).

CONCLUSION

The FABP4 level is associated with DR severity and has the potential as a serum biomarker for DR prediction.

Diabetic Retinopathy and Periodontitis: Implications from a Systematic Review and Meta-Analysis

BACKGROUND

Diabetes mellitus, a chronic metabolic disorder affecting millions worldwide, is associated with microvascular complications, including diabetic retinopathy (DR) and periodontitis. Understanding their interrelationship is crucial for comprehensive patient care.

OBJECTIVE

This systematic review and meta-analysis aim to investigate the association between DR and periodontitis in patients with Type 1 and Type 2 diabetes.

METHODOLOGY

Using the PECO framework, we searched PubMed/MEDLINE, Scopus, EMBASE, Google Scholar, and Web of Science databases (Inception to April 2023) for studies on the association between DR and periodontitis. Ten studies (n = 1828 participants), including observational and cross-sectional studies, met the inclusion criteria. We conducted qualitative synthesis, risk of bias analysis using the ROBINS-E tool, Grading of Recommendations, Assessment, Development, and Evaluations assessment (GRADE), and random-effects meta-analysis.

RESULTS

Eight studies found a significant association between severe periodontitis (pocket depth ≥5 mm) and DR, while two found no association. Meta-analysis of 843 participants showed diabetics with periodontitis had 4.48 times higher odds (95% confidence interval: 1.67-12.07, P = .003) of developing retinopathy compared to diabetics without periodontitis. High heterogeneity was observed (I2 = 86%). Subgroup analysis by diabetes type showed no significant difference. The overall GRADE level of evidence was very low.

CONCLUSION

While most included studies suggest an association between severe periodontitis and increased DR risk, the overall certainty of evidence is low. These findings highlight the potential importance of periodontal health in diabetic patients. High-quality longitudinal studies with adequate control of confounders are required to determine if periodontitis contributes to the progression of DR or if the conditions are merely coincidentally related.

Efficacy of Intravitreal Dexamethasone Implant (Ozurdex®) in Naïve and Refractory Patients with Different Morphological Subtypes of Diabetic Macular Edema

Background and Objectives: To investigate anatomical and functional outcomes in different morphological subtypes of diabetic macular edema (DME) treated with an intravitreal dexamethasone implant (Ozurdex) over 6 months follow-up. Materials and Methods: A retrospective, comparative study on patients with DME who received an intravitreal dexamethasone implant. Best-corrected visual acuity (BCVA), central subfoveal thickness (CST) and maximum CST on optical coherence tomography (OCT) were measured. The recruits were divided into three groups based on the morphological patterns of DME: serous retinal detachment (SRD), cystic macular edema (CME) and diffuse retinal thickening (DRT). The presence or absence of previous treatment were considered as being previously treated with anti-VEGF (PT) vs. naïve eyes (TN). All subjects received a single injection of the dexamethasone implant. The primary outcomes included changes in BCVA, CST and CSTMax at 2-, 4- and 6-months of follow-up. Results: CST was significantly reduced following one dexamethasone injection in the whole cohort from a total mean value of 513.3 μm to 368.2 μm at 2 months, 447.2 μm at 4 months and 471.5 μm at 6 months. The change in CST was significantly greater in SRD as opposed to the DRT and CME group at all time points. Overall, BCVA improved from 0.82 at baseline to 0.75 and 0.76 LogMAR at 2 and 4 months, respectively, whilst showing an overall deterioration to 0.84 at 6 months. The CME group showed the best BCVA at 6 months. Concerning treatment status (TN vs. PT), there was no significant difference in CST at 2 and 4 months, while CST was reduced at 6 months for the PT group (p = 0.023). Similarly, BCVA was significantly better in the PT group at 6 months (p = 0.017). Conclusions: The dexamethasone implant was effective in reducing DME and providing short-term BCVA improvement. The presence of SRD was associated with more favorable anatomical results, while CME was associated with better visual acuity. Dexamethasone provided superior results in previously treated patients.

Dose-Dependent Relationship Between Long-Term Metformin Use and the Risk of Diabetic Retinopathy: A Population-Based Cohort Study

BACKGROUND AND OBJECTIVE

Recent research has raised concerns about the association between metformin treatment in patients with diabetes mellitus (DM) and an increased risk of diabetic retinopathy. We sought to investigate this relationship, specifically examining if metformin use affects diabetic retinopathy risk in a dose-dependent manner.

METHODS

This study was a secondary data analysis based on a nationwide population database in Taiwan. Patients with new-onset DM, an age of 20 years or older, and a diagnosis of type 2 DM received at any time during 2002-2013 were included in the study. Patients diagnosed with new-onset type 2 DM between 2002 and 2013 were enrolled as the study population. We divided them into two groups: those treated with metformin and those treated with sulfonylureas. A Cox proportional hazards model was employed to estimate the risk of diabetic retinopathy after 5 years of follow-up, including cumulative defined daily dose and intensity of metformin treatment.

RESULTS

A total of 241,231 patients received treatment with metformin, while 152,617 patients were treated with sulfonylureas. Compared with patients treated with sulfonylureas, patients who received metformin treatment, at a cumulative defined daily dose < 30, had a lower risk of diabetic retinopathy (adjusted hazard ratio = 0.77; 95% confidence interval 0.60-0.98). However, those with varying defined daily doses, especially at a higher metformin treatment level (> 25 defined daily dose), had a 2.43 times higher risk of diabetic retinopathy (95% confidence interval 1.37-4.30) compared with patients treated with sulfonylureas.

CONCLUSIONS

Patients with DM treated with a lower cumulative dosage of metformin showed beneficial effects that were associated with a lower risk of diabetic retinopathy. In contrast, a higher intensity of metformin use had a greater risk of diabetic retinopathy.

Visual Acuity Outcomes and Influencing Factors in a Cohort of UK Real-World Diabetic Macular Oedema Patients During the First Two Years of Anti-VEGF Treatment

BACKGROUND/OBJECTIVES

The visual acuity (VA) outcomes after the first and second years of anti-vascular endothelial growth factor (anti-VEGF) treatment in patients with diabetic macular oedema (DMO) were evaluated, and the factors associated with treatment success were investigated.

METHODS

Using Medisoft electronic medical records (UK), this retrospective cohort study analysed VA outcomes, changes, and determinants in DMO patients at year 1 and year 2 after initial anti-VEGF injection. Descriptive analysis examined baseline demographics and clinical characteristics, while regression models were used to assess associations between these factors and changes in VA.

RESULTS

728 DMO patients (1035 eyes) treated with anti-VEGFs (ranibizumab, aflibercept, or bevacizumab) at the Northern Ireland Mater Macular Clinic from 2008 to 2021 were evaluated. The mean age was 64.5 (SD 12.8) years, and 59.6% were male. In the first year, the median annual injection number and interval were 6.0 (IQR 5.0-8.0) and 6.1 weeks (IQR 5.4-7.8), respectively, and in the second year, they were 3.0 (IQR 2.0-5.0) and 10.0 weeks (IQR 6.5-20.1). In the first two treatment years, 83.4% and 79.8% of eyes had improved/stable VA (ISVA) respectively. The injection number, interval, baseline VA, age, and proliferative diabetic retinopathy (PDR) significantly impacted VA outcomes.

CONCLUSIONS

Our study confirms the effectiveness of anti-VEGF treatments in improving or maintaining vision for DMO patients, consistent with previous real-world clinical data. An elder age, a better baseline VA, low annual injection numbers (<5), and less frequent injection intervals (≥12 weeks) were negatively associated with ISVA success in the first two years. These findings have implications for managing patient expectations, allocating resources, and understanding DMO clinical management.

Vulnerable parafoveal microcirculation quadrant in patients with type 2 diabetes mellitus

Diabetic retinopathy (DR) is a leading cause of vision loss among adults. This study evaluates Optical Coherence Tomography Angiography (OCTA) vessel density (VD) as a marker for DR in diabetes mellitus (DM) patients. An observational study was conducted with 47 type 2 DM patients and 21 healthy controls. OCTA measured superficial and deep retinal VD in the parafoveal region. Statistical analyses, including logistic regression and ROC curve analysis, were used to assess the association between VD and DR presence. Results showed that DM patients had lower parafoveal superficial (46.73 vs. 52.37%, p = 0.002) and deep VD (50.35 vs. 54.26%, p = 0.019) compared to controls. Within the DM group, DR patients had lower VD in the superior parafoveal superficial layer (p = 0.042) and temporal parafoveal deep layer (p = 0.035). ROC analysis identified a cutoff of 51.86% for the temporal deep parafoveal VD, with an AUC of 0.697 (p = 0.035) and 81.8% sensitivity for DR discrimination. Reduced VD in the temporal deep parafoveal region is linked to a higher DR likelihood. OCTA-derived VD metrics offer promise for early DR detection and underscore the importance of monitoring vascular changes in DM patients.

Serum inflammation biomarkers level in cystoid and diffuse diabetic macular edema

OBJECTIVE

To assess serum inflammatory biomarker levels in patients with different subtypes of diabetic macular edema (DME).

METHODS

We retrospectively analyzed 50 eyes from 37 treatment-naïve DME patients who underwent intravitreal injection therapy between June and December 2023. Based on the morphological characteristics of macular edema in optical coherence tomography (OCT), the eyes were categorized into the cystoid macular edema (CME) group (n = 25) and diffuse retinal thickening (DRT) group (n = 25). Additionally, 25 eyes with diabetes retinopathy but without DME served as the control group. Comprehensive clinical data were reviewed, including best-corrected visual acuity (BCVA), central macular thickness (CMT), macular cube volume (VOL) and hematological examination. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) were calculated.

RESULTS

NLR and SII levels were significantly higher in the CME group compared to the DRT group and control group (all P < 0.01). The optimal ROC cutoff value of NLR for CME was 2.27, with 88.0% sensitivity and 68.0% specificity. The optimal ROC cutoff value of SII for CME was 447.33, with 84.0% sensitivity and 60.0% specificity. After initial intravitreal injection therapy, BCVA and VOL significantly improved in each group (all P < 0.01). However, no significant correlation was found between systemic inflammatory marker levels and postoperative changes in BCVA, CMT and VOL (all P > 0.05).

CONCLUSION

Our study suggests that elevated NLR and SII levels are significantly associated with CME. Elevated serum inflammatory biomarkers may indicate a higher incidence of CME in these patients.

Plasma Metabolomics Identifies Key Metabolites and Improves Prediction of Diabetic Retinopathy: Development and Validation across Multinational Cohorts

PURPOSE

To identify longitudinal metabolomic fingerprints of diabetic retinopathy (DR) and to evaluate their usefulness in predicting DR development and progression.

DESIGN

Multicenter, multiethnic cohort study.

PARTICIPANTS

This study included 17 675 participants from the UK Biobank (UKB) who had baseline prediabetes or diabetes, identified in accordance with the 2021 American Diabetes Association guidelines, and were free of baseline DR and an additional 638 participants with type 2 diabetes mellitus from the Guangzhou Diabetic Eye Study (GDES) for external validation. Diabetic retinopathy was determined by ICD-10 codes in the UKB cohort and revised ETDRS grading criteria in the GDES cohort.

METHODS

Longitudinal DR metabolomic fingerprints were identified through nuclear magnetic resonance (NMR) assay in UKB participants. The predictive value of these fingerprints for predicting DR development were assessed in a fully withheld test set. External validation and extrapolation analyses of DR progression and microvascular damage were conducted in the GDES cohort using NMR technology. Model assessments included the concordance (C) statistic, net classification improvement (NRI), integrated discrimination improvement (IDI), calibration, and clinical usefulness in both cohorts.

MAIN OUTCOME MEASURES

DR development and progression and retinal microvascular damage.

RESULTS

Of 168 metabolites, 118 were identified as candidate metabolomic fingerprints for future DR development. These fingerprints significantly improved the predictability for DR development beyond traditional indicators (C statistic, 0.802 [95% confidence interval (CI), 0.760-0.843] vs. 0.751 [95% CI, 0.706-0.796]; P = 5.56 × 10-4). Glucose, lactate, and citrate were among the fingerprints validated in the GDES cohort. Using these parsimonious and replicable fingerprints yielded similar improvements for predicting DR development (C statistic, 0.807 [95% CI, 0.711-0.903] vs. 0.617 [95% CI, 0.494-0.740]; P = 1.68 × 10-4) and progression (C statistic, 0.797 [95% CI, 0.712-0.882] vs. 0.665 [95% CI, 0.545-0.784]; P = 0.003) in the external GDES cohort. Improvements in NRIs, IDIs, and clinical usefulness also were evident in both cohorts (all P < 0.05). In addition, lactate and citrate were associated with microvascular damage across macular and optic nerve head regions among Chinese GDES (all P < 0.05).

CONCLUSIONS

Metabolomic profiling may be effective in identifying robust fingerprints for predicting future DR development and progression, providing novel insights into the early and advanced stages of DR pathophysiology.

FINANCIAL DISCLOSURE(S)

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

Harmonizing Unets: Attention Fusion module in cascaded-Unets for low-quality OCT image fluid segmentation

Optical coherence tomography (OCT) is widely used for its high resolution. Accurate OCT image segmentation can significantly improve the diagnosis and treatment of retinal diseases such as Diabetic Macular Edema (DME). However, in resource-limited regions, portable devices with low-quality output are more frequently used, severely affecting the performance of segmentation. To address this issue, we propose a novel methodology in this paper, including a dedicated pre-processing pipeline and an end-to-end double U-shaped cascaded architecture, H-Unets. In addition, an Adaptive Attention Fusion (AAF) module is elaborately designed to improve the segmentation performance of H-Unets. To demonstrate the effectiveness of our method, we conduct a bunch of ablation and comparative studies on three open-source datasets. The experimental results show the validity of the pre-processing pipeline and H-Unets, achieving the highest Dice score of 90.60%±0.87% among popular methods in a relatively small model size.

Semi-supervised 3D retinal fluid segmentation via correlation mutual learning with global reasoning attention

Accurate 3D segmentation of fluid lesions in optical coherence tomography (OCT) is crucial for the early diagnosis of diabetic macular edema (DME). However, higher-dimensional spatial complexity and limited annotated data present significant challenges for effective 3D lesion segmentation. To address these issues, we propose a novel semi-supervised strategy using a correlation mutual learning framework for segmenting 3D DME lesions from 3D OCT images. Our method integrates three key innovations: (1) a shared encoder with three parallel, slightly different decoders, exhibiting cognitive biases and calculating statistical discrepancies among the decoders to represent uncertainty in unlabeled challenging regions. (2) a global reasoning attention module integrated into the encoder's output to transfer label prior knowledge to unlabeled data; and (3) a correlation mutual learning scheme, enforcing mutual consistency between one decoder's probability map and the soft pseudo labels generated by the other decoders. Extensive experiments demonstrate that our approach outperforms state-of-the-art (SOTA) methods, highlighting the potential of our framework for tackling the complex task of 3D retinal lesion segmentation.

Patient Preferences with Anti-Vascular Endothelial Growth Factor Treatment for Neovascular Age-Related Macular Degeneration and Diabetic Macular Edema: A Multinational Discrete Choice Experiment Study

INTRODUCTION

New anti-vascular endothelial growth factor (VEGF) treatments are emerging for the treatment of diabetic macular edema (DME)/neovascular age-related macular degeneration (nAMD). This study aimed to explore the treatment attributes patients find important when deciding on treatment options.

METHODS

This noninterventional survey study assessed treatment preferences through a discrete choice experiment (DCE) among patients with DME/nAMD in the USA, Canada, France, Italy, Spain, and the UK. The DCE design was informed by a targeted literature review and qualitative interview research and included five treatment attributes: mode of administration, frequency of examinations, frequency of injections or refills, likely change in visual acuity, and eye-related side effects. Conditional logit models were used to analyze the choice data.

RESULTS

Overall, 537 patients completed the DCE (DME, n = 173; nAMD, n = 364). Patients reported preferring "injection" over "implant surgery and refills" and better visual outcomes over "stabilization," which were also the most important attributes driving preference (35.1% and 31.5%, respectively). They also showed a preference for less-frequent treatment and examinations and for "mild-moderate, frequent" over "severe, rare" side effects. These findings were generally consistent across the two conditions, although significant differences were found depending on anti-VEGF treatment duration (nAMD, DME) and number of reported barriers (nAMD).

CONCLUSION

Patient preferences for treatment are driven by several factors. Considering these preferences is essential when designing/introducing new therapies. Individual treatment preferences should be identified and given key consideration when helping patients select from an expanding array of treatment options.

Study of Imaging Biomarkers as a Prognostic Factor and Guide in the Management of Diabetic Macular Oedema

Background: Diabetic macular oedema (DME) is a major cause of vision impairment in individuals with diabetes mellitus, characterised by fluid accumulation in the macula due to increased vascular permeability. The growing prevalence of diabetes worldwide has led to an increasing burden of DME on healthcare systems. While current treatment options such as anti-vascular endothelial growth factor (anti-VEGF) injections, corticosteroids, and laser therapy exist, the variability in patient responses highlights the need for reliable prognostic tools. Imaging biomarkers, particularly those identified using optical coherence tomography (OCT) and fluorescein angiography (FA), play a critical role in diagnosing and managing DME. This study evaluates the prognostic significance of these biomarkers in predicting disease progression and treatment outcomes. Materials and methods: This prospective observational study was conducted at Gandhi Medical College and Hamidia Hospital, Bhopal, Madhya Pradesh, from August 2022 to June 2024. A total of 123 patients with Type II diabetes mellitus diagnosed with DME were included through consecutive sampling. Comprehensive assessments, including visual acuity, slit-lamp examination, fundus evaluation, FA, and OCT, were performed. Key imaging biomarkers, such as central subfield thickness (CST), disorganisation of retinal inner layers (DRIL), intraretinal cysts, hyperreflective foci, and vitreomacular interface (VMI) abnormalities, were evaluated. Correlations between biomarkers, best-corrected visual acuity (BCVA), metabolic markers (HbA1c, serum cholesterol), and disease severity were analysed using statistical tools, including the chi-square test and Pearson's correlation. Results: The most common biomarkers observed were DRIL with external limiting membrane (ELM) disruption (38, 31%), intraretinal cysts with ELM disruption (36, 29.3%), and hyperreflective foci (28, 22.8%). VMI abnormalities were noted in 14 (11.4%) cases, while subretinal fluid with serous retinal detachment was present in seven patients (5.7%). Significant negative correlations were found between BCVA (LogMAR) and biomarkers, with intraretinal cysts (-0.526, p=0.003) and VMI abnormalities (-0.492, P=0.002) having the strongest associations. Higher glycosylated haemoglobin (HbA1c) levels were significantly associated with intraretinal cysts (P=0.014) and VMI abnormalities (P=0.042), while higher cholesterol levels correlated with hyperreflective foci (P=0.011) and subretinal fluid (P=0.014). Patients with proliferative diabetic retinopathy (PDR) exhibited worse visual outcomes and greater CST compared to those with non-proliferative diabetic retinopathy (NPDR). Conclusion: Imaging biomarkers, particularly DRIL, intraretinal cysts, and VMI abnormalities, significantly correlate with visual acuity and metabolic control in DME patients. These findings underscore the importance of OCT in the prognostic assessment of DME and highlight the need for personalised treatment approaches based on biomarker profiles. Future studies should focus on long-term follow-up and explore the potential for integrating these biomarkers into clinical decision-making to improve patient outcomes.

Comparison of the Risk of Diabetic Retinopathy Between Sodium-Glucose Cotransporter-2 Inhibitors and Dipeptidyl Peptidase-4 Inhibitors in Patients with Type 2 Diabetes Mellitus in Japan: A Retrospective Analysis of Real-World Data

INTRODUCTION

Diabetic retinopathy (DR), a microvascular complication of type 2 diabetes mellitus (T2DM), is a leading cause of blindness and has detrimental effects on patients' quality of life. We compared the risk of DR diagnosis with sodium-glucose cotransporter-2 inhibitors (SGLT2i) versus dipeptidyl peptidase-4 inhibitors (DPP-4i) in patients with T2DM in Japan.

METHODS

This Japanese retrospective cohort study used the JMDC Claims Database (data collected from January 2015 to September 2022). Patients with T2DM and no record of microvascular or macrovascular diseases who were newly treated with an SGLT2i (23,061 patients) or a DPP-4i (53,986 patients) were matched 1:1 using propensity score (10,166 per matched group). Incidence rates (IRs) and cumulative IRs of DR diagnosis were calculated for each treatment group; hazard ratio (HR) and its 95% confidence interval (CI) were calculated using Cox proportional hazard models to compare the risk between the groups.

RESULTS

The IR of DR diagnosis was 46.23 and 57.12 per 1000 person-years in the SGLT2i and DPP-4i groups, respectively, with a significantly lower risk in the SGLT2i group than in the DPP-4i group (HR 0.83, 95% CI 0.75-0.92, P = 0.0003).

CONCLUSIONS

In this study, the risk of DR diagnosis was lower with SGLT2i compared with DPP-4i in patients with T2DM without microvascular and macrovascular diseases in Japan. Findings suggest that early SGLT2i treatment may be beneficial in preventing DR development in early-stage T2DM. Graphical abstract available for this article.

Ophthalmic Use of Targeted Biologics in the Management of Intraocular Diseases: Current and Emerging Therapies

BACKGROUND

Monoclonal antibodies (mAbs) have demonstrated substantial potential in the treatment of intraocular diseases. This review aimed to comprehensively evaluate the applications, efficacy, and safety of mAbs in the management of intraocular conditions.

METHODS

A comprehensive literature search was conducted in major medical databases through July 2024. Relevant studies on monoclonal antibodies for intraocular diseases were included. Two independent researchers screened the literature, extracted data, and assessed study quality. Cost-effectiveness analyses were also reviewed.

RESULTS

Anti-vascular endothelial growth factor (VEGF) antibodies, such as bevacizumab, ranibizumab, and aflibercept, showed significant therapeutic effects in neovascular age-related macular degeneration (NVAMD), diabetic macular edema (DME), and retinal vein occlusion (RVO). Tumor necrosis factor-alpha (TNF-α) inhibitors demonstrated promising results in treating noninfectious uveitis. Complement system-targeted therapies like pegcetacoplan offered new options for geographic atrophy. Anti-VEGF antibodies showed potential in managing retinopathy of prematurity (ROP). However, challenges persist, including high costs, potential drug resistance, and limited long-term safety data in certain scenarios.

CONCLUSIONS

Monoclonal antibodies are vital for treating intraocular diseases, but continuous innovation and rigorous clinical evaluation are essential. Future research should focus on developing novel delivery systems, exploring combination therapies, conducting long-term follow-up studies, and investigating personalized treatment strategies to provide safer, more effective, and cost-effective therapeutic solutions.

Insights to Ang/Tie signaling pathway: another rosy dawn for treating retinal and choroidal vascular diseases

Retinal neurovascular unit (NVU) is a multi-cellular structure that consists of the functional coupling between neural tissue and vascular system. Disrupted NVU will result in the occurrence of retinal and choroidal vascular diseases, which are characterized by the development of neovascularization, increased vascular permeability, and inflammation. This pathological entity mainly includes neovascular age-related macular degeneration (neovascular-AMD), diabetic retinopathy (DR) retinal vein occlusion (RVO), and retinopathy of prematurity (ROP). Emerging evidences suggest that the angopoietin/tyrosine kinase with immunoglobulin and epidermal growth factor homology domains (Ang/Tie) signaling pathway is essential for the development of retinal and choroidal vascular. Tie receptors and their downstream pathways play a key role in modulating the vascular development, vascular stability, remodeling and angiogenesis. Angiopoietin 1 (Ang1) is a natural agonist of Tie2 receptor, which can promote vascular stability. On the other hand, angiopoietin 2 (Ang2) is an antagonist of Tie2 receptor that causes vascular instability. Currently, agents targeting the Ang/Tie signaling pathway have been used to inhibit neovascularization and vascular leakage in neovascular-AMD and DR animal models. Particularly, the AKB-9778 and Faricimab have shown promising efficacy in improving visual acuity in patients with neovascular-AMD and DR. These experimental and clinical evidences suggest that activation of Ang/Tie signaling pathway can inhibit the vascular permeability, neovascularization, thereby maintaining the normal function and structure of NVU. This review seeks to introduce the versatile functions and elucidate the modulatory mechanisms of Ang/Tie signaling pathway. Recent pharmacologic therapies targeting this pathway are also elaborated and summarized. Further translation of these findings may afford a new therapeutic strategy from bench to bedside.

The comorbidity burden of type 2 diabetes mellitus (T2DM): sex differences and associated factors among 830 cases in North-Eastern Morocco

Background and aim

Type 2 diabetes is prone to numerous comorbidities resulting from complex mechanisms involving hyperglycemia, insulin resistance, low-grade inflammation and accelerated atherogenesis. The purpose of the present study was to investigate these disorders and their associated risk factors according to patient sex in a population of type 2 diabetics in North-Eastern Morocco.

Methods

This study was conducted in a medical analysis laboratory over a 1-year period from 01/10/2018 to 01/10/2019. This epidemiological study was carried out on 830 subjects aged 18 and over. Quantitative variables were expressed as means ± standard deviation, and qualitative variables as frequencies and percentages. Hypothesis tests used to compare means and proportions were Student's t-test and Chi-square test of independence, respectively. Logistic regression was used to predict risk factors for each diabetes.

Results

830 patients were surveyed. 95.66% had diabetes-related comorbidities. Hypertension (23.7%), nephropathy (18.19%), dyslipidemia (14.82%), thyroid dysfunction (10.72%), cataract (10.12%), diabetic foot (7.23%), ketoacidosis (6.27%), retinopathy (3.49%), and skin disorders (2.77%) were observed. Sex was associated with dyslipidemia (p = 0.025), hypertension (p = 0.032) and retinopathy (p = 0.029). Uncontrolled blood sugar, unbalanced lipid profile, age, physical activity, obesity, smoking, and alcohol consumption were risk factors with differential involvement in the occurrence of the mentioned pathologies.

Conclusions

The results of our study showed that a significant proportion of the population suffers from diabetic comorbidities. To meet this challenge, further research is needed to identify the mechanisms of action of these factors, to control them and combat diabetogenic environments by setting up adapted educational programs.

Correlation of limited-early-response status with 12-month CST, BVA, and machine learning-quantified retinal fluid in diabetic macular oedema in routine clinical practice

BACKGROUND/OBJECTIVES

Anti-VEGF treatment response in DMO has been measured by changes in the central subfield thickness (CST) and best visual acuity (BVA) outcomes at 3 months after initial treatment, termed early or limited early response (ER/LER). This study correlates LER with 12-month BVA, CST, and retinal fluid volumes quantified by a machine learning algorithm on optical coherence tomography (OCT).

SUBJECTS/METHODS

The study included treatment naïve DMO patients ≥ 18 years with OCT scans at baseline (M0), M3, M6, and M12. The 220 patients were categorized as limited early responders (LER) if they had ≤ 10% CST reduction and/or < 5 ETDRS letter gain at M3. BVA, CST, and subretinal (SRF), intraretinal (IRF), and total retinal (TRF) fluid volumes quantified by a machine learning algorithm were compared between groups and across time.

RESULTS

At M12, the anatomic LER (aLER), defined solely by CST, had significantly worse BVA and CST versus the anatomic ER (aER) group (p < 0.001). Retinal fluid M12 outcomes did not significantly vary between all LER and ER groups. No significant BVA, CST, TRF, and IRF variance across time for LER was found (p > 0.1).

CONCLUSIONS

BVA and CST M12 outcomes vary by aLER/aER status indicating that CST may be a strong predictor of treatment outcomes, while retinal fluid volumes were not predicted by LER status.

Tracking Macular Sensitivity and Inner Retinal Thickness in Long-Term Type 1 Diabetes: A Five-Year Prospective Examination in Patients without Diabetic Retinopathy

The aim of the study is to compare macular sensitivity and retinal thickness in patients with long-term type 1 diabetes mellitus (DM1) without diabetic retinopathy (DR) after 5 years of follow-up. Thirty-two eyes from 32 long-term DM1 patients without DR were included. All participants underwent a complete ophthalmological examination, including microperimetry and spectral domain optical coherence tomography (SD-OCT). The data were compared with results from 5 years prior. The mean age of the DM1 patients was 43.19 ± 10.17 years, with a mean disease duration of 29.84 ± 8.98 years and good glycemic control. In 2023, patients exhibited a significantly worse best corrected visual acuity (BCVA) compared to 2018 (p < 0.001). DM1 patients did not show statistically significant changes in macular sensitivity over the 5-year follow-up period. Macular integrity showed significant differences between the two time points (p = 0.045). Retinal thickness showed significant differences, particularly in inner retinal layers (IRL) across most of the ETDRS areas. Long-term DM1 patients without DR lesions showed worsened macular integrity and a lower BCVA in 2023. Additionally, they displayed significant alterations in retinal thicknesses, especially in the IRL, between 2018 and 2023. These findings suggest that even in the absence of visible DR, long-term DM1 patients may experience subclinical retinal changes and functional deterioration over time, highlighting the importance of regular monitoring for the early detection and management of potential complications.

Prior-guided attention fusion transformer for multi-lesion segmentation of diabetic retinopathy

To solve the issue of diagnosis accuracy of diabetic retinopathy (DR) and reduce the workload of ophthalmologists, in this paper we propose a prior-guided attention fusion Transformer for multi-lesion segmentation of DR. An attention fusion module is proposed to improve the key generator to integrate self-attention and cross-attention and reduce the introduction of noise. The self-attention focuses on lesions themselves, capturing the correlation of lesions at a global scale, while the cross-attention, using pre-trained vessel masks as prior knowledge, utilizes the correlation between lesions and vessels to reduce the ambiguity of lesion detection caused by complex fundus structures. A shift block is introduced to expand association areas between lesions and vessels further and to enhance the sensitivity of the model to small-scale structures. To dynamically adjust the model's perception of features at different scales, we propose the scale-adaptive attention to adaptively learn fusion weights of feature maps at different scales in the decoder, capturing features and details more effectively. The experimental results on two public datasets (DDR and IDRiD) demonstrate that our model outperforms other state-of-the-art models for multi-lesion segmentation.

Caregiver Experience Survey of Anti-Vascular Endothelial Growth Factor Treatment for Diabetic Macular Edema and Neovascular Age-Related Macular Degeneration

INTRODUCTION

Diabetic macular edema (DME) and neovascular age-related macular degeneration (nAMD) require frequent anti-vascular endothelial growth factor (VEGF) treatment and monitoring visits. We aimed to understand the burden of treatment on caregivers.

METHODS

This multinational, noninterventional study used a cross-sectional survey of adult patients with DME or nAMD treated with anti-VEGF injections in the USA, Canada, France, Italy, Spain, and the UK. The survey assessed caregivers' sociodemographic characteristics, patient relationships, patients' clinical history and treatment experiences, caregivers' experiences, and the Caregiver Reaction Assessment of caregiving burden.

RESULTS

Caregivers for patients with DME (n = 30) and nAMD (n = 95) completed surveys. Mean ± standard deviation (SD) age was 64.0 ± 13.4 years, and most were female (71.2%), white (70.4%), married (66.4%), and from Europe (67.2%). Most were caring for their mother/father or partner/spouse (85.6%). Mean ± SD length of time as a caregiver was 9.1 ± 10.0 years. Caregivers estimated they provided support for 4.2 ± 2.9 days/week and 6.0 ± 7.1 h/day on average. Nearly half of caregivers (45.6%) reported some impairment in daily activities, and more than two-thirds (70.5%) of working caregivers (n = 44) reported work absenteeism due to anti-VEGF treatment/monitoring appointments. At least one treatment barrier was reported by 66.7% and 50.5% of caregivers of patients with DME and nAMD, respectively, which were related to coronavirus disease 2019- (38.4%), clinic- (18.4%), social-/health- (13.6%), treatment- (10.4%), or financial-related factors (4.8%). Caregiver Reaction Assessment scores indicated mild-to-moderate burden, with higher caregiver schedule disruption scores associated with an increasing number of anti-VEGF treatment/monitoring visits among DME caregivers (r = 0.61).

CONCLUSION

Caregivers devote substantial time to caregiving, leading to schedule disruptions and absenteeism for some working caregivers. Positive and negative impacts on caregiver mental health were reported.

Real-Life Results after the Administration of a Single 0.19 mg Fluocinolone Acetonide (ILUVIEN®) Implant in Patients with Refractory Diabetic Macular Edema

INTRODUCTION

The aim of this study was to evaluate real-life data on the functional and anatomical outcome of intravitreal fluocinolone acetonide (FAc) in patients with refractory diabetic macular edema (DME).

METHODS

Retrospective study on 44 eyes with chronic DME that received intravitreal FAc implant and were previously treated with intravitreal dexamethasone, triamcinolone, or anti-vascular endothelial growth factor. We assessed best-corrected visual acuity (BCVA), central maximum thickness (CMT), and foveal thickness (FT) as measured by spectral-domain optical coherence tomography (Spectralis OCT; Heidelberg Engineering). Secondary outcomes were intraocular pressure (IOP), adverse events, time to additional treatments.

RESULTS

The FAc implant significantly reduced the CMT (baseline 541.23 ± 155.29 µm, p < 0.001) and FT (baseline 460.34 ± 139.28 µm, p < 0.001) for up to 36 months. Despite postoperative visual improvement over time, BCVA did not significantly shift from baseline (0.55 ± 0.38 logMAR, p = 0.568). The FAc implant effect diminished after 21.34 ± 12.74 months. IOP increased in 9% of eyes (n = 4) but was well controlled under topical (n = 1) or surgical therapy (n = 3).

CONCLUSION

Even though patients' visual recovery does not benefit significantly, the FAc implant addresses the important pillars of chronic DME therapy regarding reduced injection frequency and reduced DME.

Global research trends and hotspots of oxidative stress in diabetic retinopathy (2000-2024)

Introduction

Oxidative stress has been identified as a major contributor to the pathogenesis of DR, and many diagnostic and therapeutic strategies have been developed to target oxidative stress. Our aim was to understand the contribution of the country of origin of the publication, the institution, the authors, and the collaborative relationship between them.

Methods

We performed a bibliometric analysis to summarize and explore the research hotspots and trends of oxidative stress in the DR.

Results

We observe an upward trend in the number of posts on related topics from year to year. Expanding on this, Queens University Belfast is the most influential research institution. Current research hotspots and trends focus on the mechanism of autophagy and NLRP3 inflammasome's role in oxidative stress in DR.

Discussion

We conducted a multi-dimensional analysis of the research status of oxidative stress in diabetic retinopathy through bibliometric analysis, and proposed possible future research trends and hotspots.

Fatty Acid-Binding Protein 4-Mediated Regulation Is Pivotally Involved in Retinal Pathophysiology: A Review

Fatty acid-binding proteins (FABPs), a family of lipid chaperone molecules that are involved in intracellular lipid transportation to specific cellular compartments, stimulate lipid-associated responses such as biological signaling, membrane synthesis, transcriptional regulation, and lipid synthesis. Previous studies have shown that FABP4, a member of this family of proteins that are expressed in adipocytes and macrophages, plays pivotal roles in the pathogenesis of various cardiovascular and metabolic diseases, including diabetes mellitus (DM) and hypertension (HT). Since significant increases in the serum levels of FABP4 were detected in those patients, FABP4 has been identified as a crucial biomarker for these systemic diseases. In addition, in the field of ophthalmology, our group found that intraocular levels of FABP4 (ioFABP4) and free fatty acids (ioFFA) were substantially elevated in patients with retinal vascular diseases (RVDs) including proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), for which DM and HT are also recognized as significant risk factors. Recent studies have also revealed that ioFABP4 plays important roles in both retinal physiology and pathogenesis, and the results of these studies have suggested potential molecular targets for retinal diseases that might lead to future new therapeutic strategies.

Estimating the prevalence of diabetic retinopathy in electronic health records with massive missing labels

Objective

The paper aims to address the problem of massive unlabeled patients in electronic health records (EHR) who potentially have undiagnosed diabetic retinopathy (DR). It is desired to estimate the actual DR prevalence in EHR with 96 % missing labels.

Materials and methods

The Cerner Health Facts data are used in the study, with 3749 labeled DR patients and 97,876 unlabeled diabetic patients. This extensive dataset spans the demographics of the United States over the past two decades. We implemented state-of-art positive-unlabeled learning methods, including ensemble-based support vector machine, ensemble-based random forest, and Bayesian finite mixture modeling.

Results

The estimated DR prevalence in the population represented by Cerner EHR is approximately 25 % and the classification techniques generally achieve an AUC of around 87 %. As a by-product, a predictive inference on the risk of DR based on a patient's personalized medical information is derived.

Discussion

Missing labels is a common issue for EHR data quality. Ignoring these missing labels can lead to biased results in the analyses of EHR data. The problem is especially severe in the context of DR. It is thus important to use machine learning or statistical tools to identify the unlabeled patients. The tool in this paper helps both data analysts and clinicians in their practices.

ROBIN: a randomised, double-masked, placebo-controlled Phase IIa study of the AOC3 inhibitor BI 1467335 in diabetic retinopathy

OBJECTIVE

To evaluate the safety and efficacy of BI 1467335 in patients with non-proliferative diabetic retinopathy (NPDR).

METHODS

ROBIN is a Phase IIa, double-masked, randomised, placebo-controlled study (NCT03238963). Patients with NPDR and without centre-involved diabetic macular oedema were included; all had a best corrected visual acuity letter score of ≥70 Early Treatment Diabetic Retinopathy Study letters in the study eye at screening. Patients received oral BI 1467335 10 mg or placebo once daily for 12 weeks. Post-treatment follow-up was 12 weeks. The primary endpoint was the proportion of patients over the 24 weeks with ocular adverse events (AEs). Secondary endpoints were the proportion of patients with ≥2-step improvement from baseline in DRSS severity level at Week 12 and the proportion of patients with non-ocular AEs at 24 weeks.

RESULTS

Seventy-nine patients entered the study (BI 1467335, n = 40; placebo, n = 39). The proportion of patients with ocular AEs over 24 weeks was greater in the BI 1467335 versus the placebo group (35.0% vs 23.1%, respectively). Treatment-related AEs were reported for similar numbers of patients in the placebo and BI 1467335 group (7.7% vs 7.5%, respectively). At Week 12, 5.7% (n = 2) of patients in the BI 1467335 group had a 2-step improvement in DRSS severity level from baseline, compared with 0% in the placebo group.

CONCLUSIONS

BI 1467335 was well tolerated by patients with NPDR. There was a high variability in DRSS levels for individual patients over time, with no clear efficacy signal.

Gene Therapy for Non-Hereditary Retinal Disease: Age-Related Macular Degeneration, Diabetic Retinopathy, and Beyond

Gene therapy holds promise as a transformative approach in the treatment landscape of age-related macular degeneration (AMD), diabetic retinopathy (DR), and diabetic macular edema (DME), aiming to address the challenges of frequent intravitreal anti-vascular endothelial growth factor (VEGF) injections. This manuscript reviews ongoing gene therapy clinical trials for these disorders, including ABBV-RGX-314, ixoberogene soroparvovec (ixo-vec), and 4D-150. ABBV-RGX-314 utilizes an adeno-associated virus (AAV) vector to deliver a transgene encoding a ranibizumab-like anti-VEGF antibody fragment, demonstrating promising results in Phase 1/2a and ongoing Phase 2b/3 trials. Ixo-vec employs an AAV2.7m8 capsid for intravitreal delivery of a transgene expressing aflibercept, showing encouraging outcomes in Phase 1 and ongoing Phase 2 trials. 4D-150 utilizes an evolved vector to express both aflibercept and a VEGF-C inhibitory RNAi, exhibiting positive interim results in Phase 1/2 studies. Other therapies reviewed include EXG102-031, FT-003, KH631, OLX10212, JNJ-1887, 4D-175, and OCU410. These therapies offer potential advantages of reduced treatment frequency and enhanced safety profiles, representing a paradigm shift in management towards durable and efficacious cellular-based biofactories. These advancements in gene therapy hold promise for improving outcomes in AMD and addressing the complex challenges of DME and DR, providing new avenues for the treatment of diabetic eye diseases.

Cross-modal attention network for retinal disease classification based on multi-modal images

Multi-modal eye disease screening improves diagnostic accuracy by providing lesion information from different sources. However, existing multi-modal automatic diagnosis methods tend to focus on the specificity of modalities and ignore the spatial correlation of images. This paper proposes a novel cross-modal retinal disease diagnosis network (CRD-Net) that digs out the relevant features from modal images aided for multiple retinal disease diagnosis. Specifically, our model introduces a cross-modal attention (CMA) module to query and adaptively pay attention to the relevant features of the lesion in the different modal images. In addition, we also propose multiple loss functions to fuse features with modality correlation and train a multi-modal retinal image classification network to achieve a more accurate diagnosis. Experimental evaluation on three publicly available datasets shows that our CRD-Net outperforms existing single-modal and multi-modal methods, demonstrating its superior performance.

Proteomic analysis of diabetic retinopathy identifies potential plasma-protein biomarkers for diagnosis and prognosis

OBJECTIVES

To identify molecular pathways and prognostic- and diagnostic plasma-protein biomarkers for diabetic retinopathy at various stages.

METHODS

This exploratory, cross-sectional proteomics study involved plasma from 68 adults, including 15 healthy controls and 53 diabetes patients for various stages of diabetic retinopathy: non-diabetic retinopathy, non-proliferative diabetic retinopathy, proliferative diabetic retinopathy and diabetic macular edema. Plasma was incubated with peptide library beads and eluted proteins were tryptic digested, analyzed by liquid chromatography-tandem mass-spectrometry followed by bioinformatics.

RESULTS

In the 68 samples, 248 of the 731 identified plasma-proteins were present in all samples. Analysis of variance showed differential expression of 58 proteins across the five disease subgroups. Protein-Protein Interaction network (STRING) showed enrichment of various pathways during the diabetic stages. In addition, stage-specific driver proteins were detected for early and advanced diabetic retinopathy. Hierarchical clustering showed distinct protein profiles according to disease severity and disease type.

CONCLUSIONS

Molecular pathways in the cholesterol metabolism, complement system, and coagulation cascade were enriched in patients at various stages of diabetic retinopathy. The peroxisome proliferator-activated receptor signaling pathway and systemic lupus erythematosus pathways were enriched in early diabetic retinopathy. Stage-specific proteins for early - and advanced diabetic retinopathy as determined herein could be 'key' players in driving disease development and potential 'target' proteins for future therapies. For type 1 and 2 diabetes mellitus, the proteomic profiles were especially distinct during the early disease stage. Validation studies should aim to clarify the role of the detected molecular pathways, potential biomarkers, and potential 'target' proteins for future therapies in diabetic retinopathy.

Intraocular drug delivery systems for Diabetic retinopathy: Current and future prospective

In pharmaceutical research and development, novel drug delivery systems represent a significant advancement aimed at enhancing the efficacy of therapeutic agents through innovative delivery mechanisms. The primary objective of these systems is to transport therapeutic compounds to specific target sites, such as tumors and afflicted tissues, with the dual purpose of mitigating side effects and toxicity associated with the drugs while concurrently augmenting therapeutic effectiveness. Numerous innovative drug delivery strategies have been scrutinized for their applicability in the context of targeted ocular drug delivery. Diverse novel carriers, including but not limited to implants, hydrogels, metal nanoparticles, Nano-liposomes, micelles, solid lipid nanoparticles (SLN), emulsions, and biodegradable nanoparticles, have been harnessed to facilitate the controlled release of pharmaceutical agents to the retina and vitreous. These carriers offer distinct advantages, such as enhanced intraocular drug delivery, precise control over drug release kinetics, heightened stability, and superior entrapment efficiency. This comprehensive review seeks to elucidate the current strides made in the realm of carriers and their contemporary applications in treating diabetic retinopathy (DR). Furthermore, it underscores these carriers' pivotal role in achieving efficacious intraocular drug delivery. Additionally, this article explores the various administration routes, potential future advancements, and the multifaceted challenges confronting the domain of novel carriers in treating DR. In conclusion, novel formulations are introduced to surmount the challenges associated with intraocular drug delivery.

Diabetic Disease of the Eye in Canada: Consensus Statements from a Retina Specialist Working Group

Despite advances in systemic care, diabetic disease of the eye (DDE) remains the leading cause of blindness worldwide. There is a critical gap of up-to-date, evidence-based guidance for ophthalmologists in Canada that includes evidence from recent randomized controlled trials. Previous guidance has not always given special consideration to applying treatments and managing DDE in the context of the healthcare system. This consensus statement aims to assist practitioners in the field by providing a spectrum of acceptable opinions on DDE treatment and management from recognized experts in the field. In compiling evidence and generating consensus, a working group of retinal specialists in Canada addressed clinical questions surrounding the four themes of disease, patient, management, and collaboration. The working group reviewed literature representing the highest level of evidence on DDE and shared their opinions on topics surrounding the epidemiology and pathophysiology of diabetic retinopathy and diabetic macular edema; diagnosis and monitoring; considerations around diabetes medication use; strategic considerations for management given systemic comorbidities, ocular comorbidities, and pregnancy; treatment goals and modalities for diabetic macular edema, non-proliferative and proliferative diabetic retinopathy, and retinal detachment; and interdisciplinary collaboration. Ultimately, this work highlighted that the retinal examination in DDE not only informs the treating ophthalmologist but can serve as a global index for disease progression across many tissues of the body. It highlighted further that DDE can be treated regardless of diabetic control, that a systemic approach to patient care will result in the best health outcomes, and prevention of visual complications requires a multidisciplinary management approach. Ophthalmologists must tailor their clinical approach to the needs and circumstances of individual patients and work within the realities of their healthcare setting.

Enhancing Diabetic Macular Edema Treatment Outcomes: Exploring the ESASO Classification and Structural OCT Biomarkers

INTRODUCTION

This study assessed the European School of Advanced Studies in Ophthalmology (ESASO) classification's prognostic value for diabetic macular edema (DME) in predicting intravitreal therapy outcomes.

METHODS

In this retrospective, multicenter study, patients aged > 50 years with type 1 or 2 diabetes and DME received intravitreal antivascular endothelial growth factor (anti-VEGF) agents (ranibizumab, bevacizumab, and aflibercept) or steroids (dexamethasone). The primary outcome was visual acuity (VA) change post-treatment, termed as functional response, measured 4-6 weeks post-third anti-VEGF or 12-16 weeks post-steroid injection, stratified by initial DME stage.

RESULTS

Of the 560 eyes studied (62% male, mean age 66.7 years), 31% were classified as stage 1 (early), 50% stage 2 (advanced), 17% stage 3 (severe), and 2% stage 4 (atrophic). Visual acuity (VA; decimal) improved by 0.12-0.15 decimals in stages 1-2 but only 0.03 decimal in stage 3 (all p < 0.0001) and 0.01 in stage 4 (p = 0.38). Even in eyes with low baseline VA ≤ 0.3, improvements were significant only in stages 1 and 2 (0.12 and 0.17 decimals, respectively). Central subfield thickness (CST) improvement was greatest in stage 3 (-229 µm, 37.6%, p < 0.0001), but uncorrelated with VA gains, unlike stages 1 and 2 (respectively: -142 µm, 27.4%; - 5 µm, 12%; both p < 0.0001). Stage 4 showed no significant CST change. Baseline disorganization of retinal inner layers and focal damage of the ellipsoid zone/external limiting membrane did not influence VA improvement in stages 1 and 2. Treatment patterns varied, with 61% receiving anti-VEGF and 39% dexamethasone, influenced by DME stage, with no significant differences between therapeutic agents.

CONCLUSION

The ESASO classification, which views the retina as a neurovascular unit and integrates multiple biomarkers, surpasses single biomarkers in predicting visual outcomes. Significant functional improvement occurred only in stages 1 and 2, suggesting reversible damage, whereas stages 3 and 4 likely reflect irreversible damage.

Effect of Race and Insurance Status on Treatment and Outcomes in Diabetic Retinopathy: Analysis of 43 274 Eyes Using the IRIS Registry

Purpose: To examine disparities in visual acuity (VA) outcomes 1 year and 2 years after initiation of diabetic retinopathy (DR) or diabetic macular edema (DME) treatment in patients based on race/ethnicity and insurance status, accounting for disease severity. Methods: This retrospective analysis used the IRIS Registry and included DR patients older than 18 years with documented antivascular endothelial growth factor (anti-VEGF) treatment and VA data for at least 2 years. International Classification of Diseases, Tenth Revision, Clinical Modification codes were used to determine the severity of DR and DME presence. VA outcomes were assessed using multivariable linear regressions and anti-VEGF drug use by multivariable logistic regressions, with race and insurance status as independent variables. Main outcome measures comprised the mean VA change at 1 year and 2 years and percentage of patients treated with bevacizumab. Results: The study included 43 274 eyes. White patients presented with a higher mean VA and lower mean DR severity than Black patients and Hispanic patients. Multivariable logistic regression showed Hispanic patients were significantly more likely to be treated with bevacizumab than White patients across all insurance types, controlling for disease severity and VA. After 1 year, the letter improvement was 1.73, 1.33, and 1.13 in White patients, Black patients, and Hispanic patients, respectively. Multivariable linear regression suggested that across races, Medicaid-insured patients had significantly smaller gains in VA than privately insured patients. Conclusions: Race-based and insurance-based differences in 1-year and 2-year outcomes after anti-VEGF treatment for DR and anti-VEGF treatment patterns suggest a need to ensure earlier and more effective treatment of minority and underserved patients in the United States.

Role of Trimetazidine in Ameliorating Endothelial Dysfunction: A Review

Endothelial dysfunction is a hallmark of cardiovascular diseases, contributing to impaired vasodilation, altered hemodynamics, and atherosclerosis progression. Trimetazidine, traditionally used for angina pectoris, exhibits diverse therapeutic effects on endothelial dysfunction. This review aims to elucidate the mechanisms underlying trimetazidine's actions and its potential as a therapeutic agent for endothelial dysfunction and associated cardiovascular disorders. Trimetazidine enhances vasodilation and hemodynamic function by modulating endothelial nitric oxide synthase activity, nitric oxide production, and endothelin-1. It also ameliorates metabolic parameters, including reducing blood glucose, mitigating oxidative stress, and dampening inflammation. Additionally, trimetazidine exerts antiatherosclerotic effects by inhibiting plaque formation and promoting its stability. Moreover, it regulates apoptosis and angiogenesis, fostering endothelial cell survival and neovascularization. Understanding trimetazidine's multifaceted mechanisms underscores its potential as a therapeutic agent for endothelial dysfunction and associated cardiovascular disorders, warranting further investigation for clinical translation.

Diabetic Retinopathy and Quality of Life: A Systematic Review and Meta-Analysis

Importance

The association between diabetic retinopathy (DR) and quality of life (QoL) has not been thoroughly investigated.

Objective

To investigate the association between DR and both vision-related QoL (VRQoL) and general health-related QoL (HRQoL).

Data Sources

MEDLINE, EBSCO, Embase, and Web of Science were searched from their inception to April 2022.

Study Selection

Studies included adults with DR and a measure of QoL.

Data Extraction and Synthesis

Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Two assumption-free meta-analyses were conducted. Analysis 1 included studies with participants without DR as the referent group to which QoL scores of participants with DR, grouped according to DR severity, were compared. Analysis 2 included all studies with participants with DR and a measure of QoL. QoL scores were pooled within categories of DR severity, and comparisons were made between these categories.

Main Outcome and Measures

QoL measured using HRQoL and VRQoL scales.

Results

A total of 93 articles were included: 79 in the meta-analyses and 14 in the narrative results. VRQoL was recorded in 54 studies, HRQoL in 26, and both in 13 studies. The most commonly used scales were the National Eye Institute 25-item Visual Function Questionnaire (VFQ-25) (n = 49) for VRQoL and the Short Form (SF) Health Survey (n = 18) for HRQoL. Thirty-five studies reported VFQ-25 composite scores. Analysis 1 consisted of 8 studies including 1138 participants with DR and 347 participants without DR. Compared with participants without DR, the composite VFQ-25 score was 3.8 (95% CI, 1.0-6.7) points lower in those with non-vision-threatening DR (NVTDR), 12.5 (95% CI, 8.5-16.5) lower in those with any DR, and 25.1 (95% CI, 22.8-27.2) lower in VTDR (P < .001 for trend). Analysis 2 consisted of 35 studies including 6351 participants with DR. The pooled mean VFQ-25 composite score was 91.8 (95% CI, 91.0-92.7) for participants with NVTDR, 77.6 (95% CI, 76.9-78.3) for any DR, and 73.2 (95% CI, 72.6-73.7) for VTDR (P < .001 for trend). HRQoL scores had weak or no associations with NVTDR and strong associations with VTDR.

Conclusions and Relevance

This study found that VRQoL declined with the presence and severity of DR. Interventions to reduce progression of DR at both early and more advanced stages could improve VRQoL.

The Development of a Novel Aflibercept Formulation for Ocular Delivery

Aflibercept is a recombinant fusion protein that is commercially available for several ocular diseases impacting millions of people worldwide. Here, we use a case study approach to examine alternative liquid formulations for aflibercept for ocular delivery, utilizing different stabilizers, buffering agents, and surfactants with the goal of improving the thermostability to allow for limited storage outside the cold chain. The formulations were developed by studying the effects of pH changes, substituting amino acids for sucrose and salt, and using polysorbate 80 or poloxamer 188 instead of polysorbate 20. A formulation containing acetate, proline, and poloxamer 188 had lower rates of aggregate formation at 4, 30, and 40°C when compared to the marketed commercial formulation containing phosphate, sucrose, sodium chloride, and polysorbate 20. Further studies examining subvisible particles after exposure to a transport stress and long-term stability at 4°C, post-translational modifications by multi-attribute method, purity by reduced and non-reduced capillary electrophoresis, and potency by cell proliferation also demonstrated a comparable or improved stability for the enhanced formulation of acetate, proline, and poloxamer 188. This enhanced stability could enable limited storage outside of the cold chain, allowing for easier distribution in low to middle income countries.

Doppler ultrasound-based evaluation of hemodynamic changes in the ophthalmic artery and central retinal artery in patients with type 1 diabetes mellitus without retinopathy and with mild non-proliferative retinopathy

Aim

Determination of blood flow parameters in the ophthalmic artery and central retinal artery using Doppler ultrasound in patients with type 1 diabetes mellitus without fundus signs of diabetic retinopathy and with mild non-proliferative retinopathy.

Material and methods

To eliminate the impact of other systemic factors on vascular flow, the study enrolled a total of 80 patients with type 1 diabetes mellitus, aged between 18 and 45 years. The study participants did not have any diabetic complications or other systemic or ocular comorbidities. The control group comprised 81 healthy individuals within a similar age range. Color Doppler ultrasound examinations of the ophthalmic artery and central retinal artery were performed to evaluate selected blood flow parameters including peak systolic velocity, end-diastolic velocity, and resistance index.

Results

Patients with type 1 diabetes mellitus exhibited statistically significant decrease in both systolic and end-diastolic velocities in the central retinal artery, accompanied by an elevation in resistance index, compared to the control group. The study revealed differences in blood flow parameters between the patients without fundus changes and those exhibiting mild non-proliferative retinopathy. Specifically, patients with retinopathy showed a significant decrease in both systolic velocity and end-diastolic velocity in the central retinal artery. No differences were observed for the same parameters in the ophthalmic artery. When analyzing the patients' blood flow parameters in relation to the degree of diabetes control, as determined by glycated hemoglobin levels, a statistically significant reduction in systolic velocity was identified in both the ophthalmic and central retinal arteries in the group with poorly controlled diabetes.

Conclusions

Examination of the orbital vessels using Doppler ultrasound in patients with type 1 diabetes mellitus holds promise as an effective method for early detection of vascular abnormalities.

[Pharmacoeconomic analysis of anti-angiogenic drugs for diabetic macular edema]

Diabetic macular edema (DME) is a degenerative disease of the macular area in diabetes mellitus and can lead to vision loss, disability, and significantly reduced quality of life. Faricimab is the only bispecific antibody for DME therapy that targets two pathogenic pathways (Ang-2 and VEGF-A).

PURPOSE

This study comparatively evaluates the clinical and economic feasibility of faricimab and other angiogenesis inhibitors in patients with DME.

MATERIAL AND METHODS

This article analyzed literature on the efficacy and safety of intravitreal injections (IVI) of ranibizumab 0.5 mg, aflibercept 2 mg, and faricimab 6 mg. A model of medical care was developed for patients with DME receiving anti-angiogenic therapy. Pharmacoeconomic analysis was performed using cost minimization and budget impact analysis (BIA) methods. Modeling time horizon was 2 years. The research was performed from the perspective of the healthcare system of the Russian Federation.

RESULTS

The efficacy and safety of faricimab in a personalized regimen (up to one IVI in 16 weeks) are comparable to those of aflibercept and ranibizumab, administered in various regimens. The use of faricimab is associated with the lowest number of IVIs. Over 2 years, the maximum costs of drug therapy were associated with the use of ranibizumab (about 914 thousand rubles), while the minimum costs were associated with the use of faricimab (614 thousand rubles). The reduction in inpatient care costs with faricimab therapy was 36% compared to aflibercept (216 and 201 thousand rubles in inpatient and day hospitals, respectively) and 82% compared to ranibizumab (486 and 451 thousand rubles in inpatient and day hospitals, respectively). BIA demonstrated that the use of faricimab will reduce the economic burden on the healthcare system by 11.3 billion rubles (9.8%) over 2 years.

CONCLUSION

The use of faricimab is a cost-effective approach to treatment of adult patients with DME in Russia.

Classification of diabetic maculopathy based on optical coherence tomography images using a Vision Transformer model

PURPOSE

To develop a Vision Transformer model to detect different stages of diabetic maculopathy (DM) based on optical coherence tomography (OCT) images.

METHODS

After removing images with poor quality, a total of 3319 OCT images were extracted from the Eye Center of the Renmin Hospital of Wuhan University and randomly split the images into training and validation sets in a 7:3 ratio. All macular cross-sectional scan OCT images were collected retrospectively from the eyes of DM patients from 2016 to 2022. One of the OCT stages of DM, including early diabetic macular oedema (DME), advanced DME, severe DME and atrophic maculopathy, was labelled on the collected images, respectively. A deep learning (DL) model based on Vision Transformer was trained to detect four OCT grading of DM.

RESULTS

The model proposed in our paper can provide an impressive detection performance. We achieved an accuracy of 82.00%, an F1 score of 83.11%, an area under the receiver operating characteristic curve (AUC) of 0.96. The AUC for the detection of four OCT grading (ie, early DME, advanced DME, severe DME and atrophic maculopathy) was 0.96, 0.95, 0.87 and 0.98, respectively, with an accuracy of 90.87%, 89.96%, 94.42% and 95.13%, respectively, a precision of 88.46%, 80.31%, 89.42% and 87.74%, respectively, a sensitivity of 87.03%, 88.18%, 63.39% and 89.42%, respectively, a specificity of 93.02%, 90.72%, 98.40% and 96.66%, respectively and an F1 score of 87.74%, 84.06%, 88.18% and 88.57%, respectively.

CONCLUSION

Our DL model based on Vision Transformer demonstrated a relatively high accuracy in the detection of OCT grading of DM, which can help with patients in a preliminary screening to identify groups with serious conditions. These patients need a further test for an accurate diagnosis, and a timely treatment to obtain a good visual prognosis. These results emphasised the potential of artificial intelligence in assisting clinicians in developing therapeutic strategies with DM in the future.

Celecoxib/Cyclodextrin Eye Drop Microsuspensions: Evaluation of In Vitro Cytotoxicity and Anti-VEGF Efficacy for Retinal Diseases

Celecoxib (CCB), a cyclooxygenase-2 inhibitor, is capable of reducing oxidative stress and vascular endothelial growth factor (VEGF) expression in retinal cells and has been shown to be effective in the treatment of diabetic retinopathy and age-related macular degeneration. However, the ocular bioavailability of CCB is hampered due to its very low aqueous solubility. In a previous study, we developed 0.5% (w/v) aqueous CCB eye drop microsuspensions (MS) containing randomly methylated β-cyclodextrin (RMβCD) or γ-cyclodextrin (γCD) and hyaluronic acid (HA) as ternary CCB/CD/HA nanoaggregates. Both formulations exhibited good physicochemical properties. Therefore, we further investigated their cytotoxicity and efficacy in a human retina cell line in this study. At a CCB concentration of 1000 μg/mL, both CCB/RMβCD and CCB/γCD eye drop MS showed low hemolysis activity (11.1 ± 0.3% or 4.9 ± 0.2%, respectively). They revealed no signs of causing irritation and were nontoxic to retinal pigment epithelial cells. Moreover, the CCB eye drop MS exhibited significant anti-VEGF activity by reducing VEGF mRNA and protein levels compared to CCB suspended in phosphate buffer saline. The ex vivo transscleral diffusion demonstrated that a high quantity of CCB (112.47 ± 37.27 μg/mL) from CCB/γCD eye drop MS was deposited in the porcine sclera. Our new findings suggest that CCB/CD eye drop MS could be safely delivered to the ocular tissues and demonstrate promising eye drop formulations for retinal disease treatment.

Switching to Conbercept in Diabetic Macular Edema After Unsatisfactory Response to Previous Intravitreal Injection of Ranibizumab

Objective

To assess the functional and anatomical effects of transitioning to conbercept intravitreal injection (IVC) treatment in patients with diabetic macular edema (DME) who had inadequate responses to prior anti-vascular endothelial growth factor (anti-VEGF) injections.

Methods

We retrospectively included eyes with persistent DME after at least 3 injections of intravitreal ranibizumab (IVR). The analysis included the assessment of best corrected visual acuity (BCVA) and central macular thickness (CMT) during 6 months after the switch.

Results

A total of 30 patients (30 eyes) were included. CMT dropped sharply from 437.8±40.67μm at baseline to 363.59±45.09,312.52 ± 39.15, 278.51 ± 37.92, and 292.59 ± 38.09 after 1, 2, 3 and 6 months of IVC, respectively (p <0.001). BCVA in log MAR units was significantly improved from 0.73±0.15 at baseline to 0.50±0.09,0.46±0.72, 0.40±0.06 and 0.48±0.04 after 1, 2, 3 and 6 months, respectively (p <0.001).

Conclusion

Switching to Conbercept effectively improved visual and anatomical structure in DME patients who had not responded satisfactorily to previous anti-VEGF injections.

Cellular-Level Analysis of Retinal Blood Vessel Walls Based on Phase Gradient Images

Diseases such as diabetes affect the retinal vasculature and the health of the neural retina, leading to vision problems. We describe here an imaging method and analysis procedure that enables characterization of the retinal vessel walls with cellular-level resolution, potentially providing markers for eye diseases. Adaptive optics scanning laser ophthalmoscopy is used with a modified detection scheme to include four simultaneous offset aperture channels. The magnitude of the phase gradient derived from these offset images is used to visualize the structural characteristics of the vessels. The average standard deviation image provides motion contrast and enables segmentation of the vessel lumen. Segmentation of blood vessel walls provides quantitative measures of geometrical characteristics of the vessel walls, including vessel and lumen diameters, wall thickness, and wall-to-lumen ratio. Retinal diseases may affect the structural integrity of the vessel walls, their elasticity, their permeability, and their geometrical characteristics. The ability to measure these changes is valuable for understanding the vascular effects of retinal diseases, monitoring disease progression, and drug testing. In addition, loss of structural integrity of the blood vessel wall may result in microaneurysms, a hallmark lesion of diabetic retinopathy, which may rupture or leak and further create vision impairment. Early identification of such structural abnormalities may open new treatment avenues for disease management and vision preservation. Functional testing of retinal circuitry through high-resolution measurement of vasodilation as a response to controlled light stimulation of the retina (neurovascular coupling) is another application of our method and can provide an unbiased evaluation of one's vision and enable early detection of retinal diseases and monitoring treatment results.

Diversity when interpreting evidence in network meta-analyses (NMAs) on similar topics: an example case of NMAs on diabetic macular oedema

BACKGROUND

Different network meta-analyses (NMAs) on the same topic result in differences in findings. In this review, we investigated NMAs comparing aflibercept with ranibizumab for diabetic macular oedema (DME) in the hope of illuminating why the differences in findings occurred.

METHODS

Studies were searched for in English and Chinese electronic databases (PubMed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, VIP; see detailed search strategy in the main body). Two independent reviewers systematically screened to identify target NMAs that included a comparison of aflibercept and ranibizumab in patients with DME. The key outcome of interest in this review is the change in best-corrected visual acuity (BCVA), including various ways of reporting (such as the proportion of participants who gain ≥ 10 ETDRS letters at 12 months; average change in BCVA at 12 months).

RESULTS

For the binary outcome of BCVA, different NMAs all agreed that there is no clear difference between the two treatments, while continuous outcomes all favour aflibercept over ranibizumab. We discussed four points of particular concern that are illustrated by five similar NMAs, including network differences, PICO (participants, interventions, comparators, outcomes) differences, different data from the same measures of effect, and differences in what is truly significant.

CONCLUSIONS

A closer inspection of each of these trials shows how the methods, including the searches and analyses, all differ, but the findings, although presented differently and sometimes interpreted differently, were similar.

Nd:YAG Laser Capsulotomy: Efficacy and Outcomes Performed by Optometrists

SIGNIFICANCE

An increasing number of optometrists are performing Nd:YAG laser capsulotomy procedures; however, there is limited published information on the outcomes of these procedures.

PURPOSE

This study aimed to assess the efficacy and safety of capsulotomy procedures performed by optometrists.

METHODS

Subjects diagnosed with posterior capsule opacification causing reduced vision and subjective visual complaints were recruited for this study. A baseline examination was performed to ensure that the subjects met all the necessary criteria. The procedure was performed by a licensed doctor of optometry at six different clinics, and each subject was monitored for visual outcome and any potential complications.

RESULTS

Subjects' Snellen visual acuity improved from an average of 20/40 to 20/23 ( P < .001) with no complications of increased intraocular pressure, inflammation, visually significant lens pitting, macular edema, or retinal detachment. Of 78 subjects who responded to a post-procedure survey, 77 (99%) reported subjective improvement in vision after capsulotomy.

CONCLUSIONS

Based on the outcomes of this study, YAG laser capsulotomies are effective treatments to improve patient vision that can be safely and effectively performed by optometrists.

Home vision monitoring in patients with maculopathy: current and future options for digital technologies

Patients with macular pathology, including that caused by age-related macular degeneration and diabetic macular oedema, must attend frequent in-clinic monitoring appointments to detect onset of disease activity requiring treatment and to monitor progression of existing disease. In-person clinical monitoring places a significant burden on patients, caregivers and healthcare systems and is limited in that it only provides clinicians with a snapshot of the patient's disease status. The advent of remote monitoring technologies offers the potential for patients to test their own retinal health at home in collaboration with clinicians, reducing the need for in-clinic appointments. In this review we discuss visual function tests, both existing and novel, that have the potential for remote use and consider their suitability for discriminating the presence of disease and progression of disease. We then review the clinical evidence supporting the use of mobile applications for monitoring of visual function from clinical development through to validation studies and real-world implementation. This review identified seven app-based visual function tests: four that have already received some form of regulatory clearance and three under development. The evidence included in this review shows that remote monitoring offers great potential for patients with macular pathology to monitor their condition from home, reducing the need for burdensome clinic visits and expanding clinicians' understanding of patients' retinal health beyond traditional clinical monitoring. In order to instil confidence in the use of remote monitoring in both patients and clinicians further longitudinal real-world studies are now warranted.

Evaluation of the Relationship Between Diabetic Macular Edema and Renal Function in a Latino Population

INTRODUCTION

Diabetic macular edema (DME) is one of the leading causes of vision impairment. The relationship between DME and estimated glomerular filtration rate (eGFR) has not been clearly evaluated in Hispanic or Latino populations. The objective of this study was to evaluate the eGFR in a Latino population with DME.

METHODS

A cross-sectional, observational, and descriptive study was carried out on the basis of a multicenter phase III clinical trial.

RESULTS

A total of 82 subjects diagnosed with DME (36 women and 46 men) were included in the study. The mean age was 61.93 ± 6.71 years. Mean values of the blood chemistry parameters glycated hemoglobin and eGFR were 7.20 ± 0.95% and 74.42 ± 26.82 mL/min/1.73 m2, respectively. The time elapsed since diagnosis of diabetes mellitus was 15.30 ± 7.35 years, while the duration of DME was 1.41 ± 1.75 years. Mean values for central macular thickness (CMT) and total macular volume (TMV) were 440.99 ± 132.22 µm and 11.97 ± 2.11 mm3, respectively. DME duration had a negative correlation with TMV (Rho - 0.26, p < 0.05) and a positive correlation with mean arterial pressure (Rho 0.26, p < 0.05). CMT was correlated with TMV (Rho 0.43, p < 0.0001) and visual acuity (Rho 0.26, p < 0.05). No significant correlations were observed between eGFR and CMT, TMV, or any demographic variable (p > 0.05). Chronic kidney disease (CKD) was associated with hypertension (OR 9.32, p = 0.035), elevated intraocular pressure (IOP) (OR 0.03, p = 0.011), and advanced age (OR 0.45, p = 0.011). CMT was significantly associated with TMV (β = 27.69, p < 0.0001).

CONCLUSIONS

We did not find a correlation between eGFR and DME. Our findings suggest that the presence of hypertension is associated with a decrease in the GFR < 60 mL/min/1.73 m2, and CKD may be associated with advanced age and elevated IOP which may increase the risk for the development of glaucoma.

TRIAL REGISTRATION

NCT05217680 (clinicaltrials.gov).

Xanthine derivative KMUP-1 ameliorates retinopathy

Retinal neovascularization (RNV) and cell apoptosis observed in retinopathy are the most common cause of vision loss worldwide. Increasing vascular endothelial growth factor (VEGF), which was driven by hypoxia or inflammation, would result in RNV. This study investigated the anti-inflammatory and anti-apoptotic xanthine-based derivative KMUP-1 on hypoxia-induced conditions in vitro and in vivo. In the oxygen-induced retinopathy animal model, KMUP-1 mitigated vaso-obliteration and neovascularization. In the cell model of hypoxic endothelium cultured at 1% O2, KMUP-1 inhibited endothelial migration and tube formation and had no cytotoxic effect on cell growth. Upregulation of pro-angiogenic factors, HIF-1α and VEGF, and pro-inflammatory cytokines, IL-1β and TNF-α, expression in the retinal-derived endothelial cells, RF/6 A cells, upon hypoxia stimulation, was suppressed by KMUP-1 treatment. RF/6 A cells treated with KMUP-1 showed a reduction of PI3K/Akt, ERK, and RhoA/ROCKs signaling pathways and induction of protective pathways such as eNOS and soluble guanylyl cyclase at 1% O2. Furthermore, KMUP-1 decreased the expression of VEGF, ICAM-1, TNF-α, and IL-1β and increased the BCL-2/BAX ratio in the oxygen-induced retinopathy mouse retina samples. In conclusion, the results of this study suggest that KMUP-1 has potential therapeutic value in retinopathy due to its triple effects on anti-angiogenesis, anti-inflammation, and anti-apoptosis in hypoxic endothelium.

Anti-vascular endothelial growth factor for diabetic macular oedema: a network meta-analysis

Background

Diabetic macular oedema (DMO) is a common complication of diabetic retinopathy. Antiangiogenic therapy with anti-vascular endothelial growth factor (anti-VEGF) can reduce oedema, improve vision, and prevent further visual loss. These drugs have replaced laser photocoagulation as the standard of care for people with DMO. In the previous update of this review, we found moderate-quality evidence that, at 12 months, aflibercept was slightly more effective than ranibizumab and bevacizumab for improving vision in people with DMO, although the difference may have been clinically insignificant (less than 0.1 logarithm of the minimum angle of resolution (logMAR), or five Early Treatment Diabetic Retinopathy Study (ETDRS) letters, or one ETDRS line).

Objectives

The objective of this updated review was to compare the effectiveness and safety of the different anti-VEGF drugs in RCTs at longer followup (24 months).

Search methods

We searched various electronic databases on 8 July 2022.

Selection criteria

We included randomised controlled trials (RCTs) that compared any anti-angiogenic drug with an anti-VEGF mechanism of action versus another anti-VEGF drug, another treatment, sham, or no treatment in people with DMO.

Data collection and analysis

We used standard Cochrane methods for pairwise meta-analysis and we augmented this evidence using network meta-analysis (NMA) methods. We used the Stata 'network' meta-analysis package for all analyses. We used the CINeMA (Confidence in Network Meta-Analysis) web application to grade the certainty of the evidence.

Main results

We included 23 studies (13 with industry funding) that enrolled 3513 people with DMO (median central retinal thickness (CRT) 460 microns, interquartile range (IQR) 424 to 482) and moderate vision loss (median best-corrected visual acuity (BCVA) 0.48 logMAR, IQR 0.42 to 0.55. One study that investigated ranibizumab versus sham and one study that mainly enrolled people with subclinical DMO and normal BCVA were not suitable for inclusion in the efficacy NMA. Consistent with the previous update of this review, we used ranibizumab as the reference drug for efficacy, and control (including laser, observation, and sham) as the reference for systemic safety. Eight trials provided data on the primary outcome (change in BCVA at 24 months, in logMAR: lower is better). We found no evidence of a difference between the following interventions and ranibizumab alone: aflibercept (mean difference (MD) -0.05 logMAR, 95% confidence interval (CI) -0.12 to 0.02; moderate certainty); bevacizumab (MD -0.01 logMAR, 95% CI -0.13 to 0.10; low certainty), brolucizumab (MD 0.00 logMAR, 95% CI -0.08 to 0.07; low certainty), ranibizumab plus deferred laser (MD 0.00 logMAR, 95% CI -0.11 to 0.10; low certainty), and ranibizumab plus prompt laser (MD 0.03 logMAR, 95% CI -0.04 to 0.09; very low certainty). We also analysed BCVA change at 12 months, finding moderate-certainty evidence of increased efficacy with brolucizumab (MD -0.07 logMAR, 95%CI -0.10 to -0.03 logMAR), faricimab (MD -0.08 logMAR, 95% CI -0.12 to -0.05), and aflibercept (MD -0.07 logMAR, 95 % CI -0.10 to -0.04) compared to ranibizumab alone, but the difference could be clinically insignificant. Compared to ranibizumab alone, NMA of six trials showed no evidence of a difference with aflibercept (moderate certainty), bevacizumab (low certainty), or ranibizumab with prompt (very low certainty) or deferred laser (low certainty) regarding improvement by three or more ETDRS lines at 24 months. There was moderate-certainty evidence of greater CRT reduction at 24 months with brolucizumab (MD -23 microns, 95% CI -65 to -1 9) and aflibercept (MD -26 microns, 95% CI -53 to 0.9) compared to ranibizumab. There was moderate-certainty evidence of lesser CRT reduction with bevacizumab (MD 28 microns, 95% CI 0 to 56), ranibizumab plus deferred laser (MD 63 microns, 95% CI 18 to 109), and ranibizumab plus prompt laser (MD 72 microns, 95% CI 25 to 119) compared with ranibizumab alone. Regarding all-cause mortality at the longest available follow-up (20 trials), we found no evidence of increased risk of death for any drug compared to control, although effects were in the direction of an increase, and clinically relevant increases could not be ruled out. The certainty of this evidence was low for bevacizumab (risk ratio (RR) 2.10, 95% CI 0.75 to 5.88), brolucizumab (RR 2.92, 95% CI 0.68 to 12.58), faricimab (RR 1.91, 95% CI 0.45 to 8.00), ranibizumab (RR 1.26, 95% CI 0.68 to 2.34), and very low for conbercept (RR 0.33, 95% CI 0.01 to 8.81) and aflibercept (RR 1.48, 95% CI 0.79 to 2.77). Estimates for Antiplatelet Trialists Collaboration arterial thromboembolic events at 24 months did not suggest an increase with any drug compared to control, but the NMA was overall incoherent and the evidence was of low or very low certainty. Ocular adverse events were rare and poorly reported and could not be assessed in NMAs.

Authors' conclusions

There is limited evidence of the comparative efficacy and safety of anti-VEGF drugs beyond one year of follow-up. We found no clinically important differences in visual outcomes at 24 months in people with DMO, although there were differences in CRT change. We found no evidence that any drug increases all-cause mortality compared to control, but estimates were very imprecise. Evidence from RCTs may not apply to real-world practice, where people in need of antiangiogenic treatment are often under-treated, and the individuals exposed to these drugs may be less healthy than trial participants.