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Research update: 533

FEATURED ARTICLE

Effect of anticoagulant/antiplatelet therapy on the development and progression of diabetic retinopathy.

BMC Ophthalmology. 2022 Mar 17

Jeng CJ, Hsieh YT, Lin CL, Wang IJ.

Background: We investigated whether antiplatelet/anticoagulant (APAC) therapy can protect patients with type 2 diabetes mellitus (T2DM) from the development or progression of diabetic retinopathy (DR).

Methods: This is a retrospective cohort study using Longitudinal Health Insurance Database in Taiwan. A total of 73,964 type 2 diabetic patients older than 20 years old were included. Hazard ration (HR) of non-proliferative DR (NPDR), proliferative DR (PDR), and diabetic macular edema (DME) were analyzed with APAC usage as a time-dependent covariate. Age, sex, comorbidities, and medicines were further adjusted in a multi-variable model. Contributions of respective APAC was investigated with sensitivity analysis.

Results: Compared with nonusers, APAC users had a lower cumulative incidence of NPDR (P < 0.001), overall incidence of NPDR (10.7 per 1000 person-years), and risk of developing NPDR (adjusted HR = 0.78, 95% CI = 0.73-0.83). However, no significant differences were observed between APAC users and nonusers in the risks of PDR or DME. Hypertension, diabetic nephropathy and diabetic neuropathy were risk factors for NDPR development, while heart disease, cardiovascular disease, peripheral arterial occlusive disease, and statin usage were covariates decreasing NPDR development. Aspirin and Dipyridamole showed significant protection against NPDR development. Clopidogrel, Ticlopidine, and warfarin showed enhanced protection in combination with aspirin usage.

Conclusions: APAC medications have a protective effect against NPDR development. Diabetic patients benefit from single use of aspirin or dipyridamole on prevention of NPDR.

DOI: 10.1186/s12886-022-02323-z

IMPACTS OF COVID-19

Drop in well-being of ARMD patients under treatment with anti-VEGF injections during the COVID-19 pandemic.

International Ophthalmology. 2022 Apr 1

Mylona I, Papadopoulou K, Roumelis S, Floros GD.

Purpose: Patients with age-related macular degeneration (ARMD) are required to follow a treatment protocol that requires regular follow-ups. The COVID-19 pandemic has created an additional burden for patients with ARMD under treatment with anti-vascular endothelial growth factor (anti-VEGF) injections, since patients face a congestion of the health system and closing of the outpatient services. This study examines the impact of the uncertainty regarding patients’ treatment on their sense of well-being.

Methods: This is a longitudinal cohort study of eighty patients who were followed during the year following the outbreak of the COVID pandemic. Patients reported their sense of well-being with the WHO-5 questionnaire and their perception and fears for the impact of the pandemic on their ongoing ARMD treatment.

Results: There was a significant drop in mental well-being during the pandemic that paralleled the self-reported impact of the pandemic on ARMD treatment. Patients who reported a higher impact of COVID-19 on their treatment had experienced a higher drop in mental wellbeing compared to those who hadn’t, with female gender being an additional risk factor. Objective measurements of visual acuity did not factor in the drop of sense of well-being.

Conclusions: The high initial level of uncertainty regarding ARMD patients’ long-term course was further exacerbated when exposed to additional uncertainties during the pandemic regarding their standard of care. Planning ahead for continuation of services and close contact with patients during similar health emergencies is of paramount importance.

DOI: 10.1007/s10792-022-02296-4

POSTERIOR SEGMENT OCULAR FINDINGS IN CRITICALLY ILL PATIENTS WITH COVID-19.

Retina. 2022 Apr 1

Romero-Castro RM, Ruiz-Cruz M, Alvarado-de la Barrera C, González-Cannata MG, Luna-Villalobos YA, García-Morales AK, Ablanedo-Terrazas Y, González-Navarro M, Ávila-Ríos S.

Purpose: To describe ophthalmological fundoscopic findings in patients with COVID-19 admitted to the intensive care unit of the largest third-level referral center for COVID-19 in Mexico City.

Methods: In this cross-sectional single-center study, consecutive patients admitted to the intensive care unit with a diagnosis of COVID-19 underwent fundus examination with an indirect ophthalmoscope. Clinical photographs were taken using a posterior-pole camera. We explored the association between ocular manifestations and demographic characteristics, inflammatory markers, hemodynamic factors, and comorbidities.

Results: Of 117 patients examined, 74 were men; the median age was 54 years (range: 45-63 years). Forty-two patients had ophthalmological manifestations (unilateral in 23 and bilateral in 19), and 10 of these patients had more than one ophthalmological manifestation. Ocular findings were papillitis (n = 13), cotton wool spots (n = 12), retinal hemorrhages (n = 5), retinal nerve fiber layer edema (n = 8), macular whitening (n = 5), retinal vascular tortuosity (n = 4), papillophlebitis (n = 3), central retinal vein occlusion (n = 1), and branch retinal vein occlusion (n = 1). Ocular fundus manifestations were not associated with demographic characteristics, inflammatory markers, hemodynamic factors, or comorbidities.

Conclusion: More than one-third of patients with severe COVID-19 had ophthalmological manifestations. The most frequent fundoscopic findings were optic nerve inflammation, microvasculature occlusion, and major vascular occlusions. We recommend long-term follow-up to prevent permanent ocular sequelae.

DOI: 10.1097/IAE.0000000000003457

DRUG TREATMENT

Intravitreal dexamethasone versus bevacizumab in Aboriginal and Torres Strait Islander patients with diabetic macular oedema: The OASIS Study (A randomised control trial).

Clinical Experimental Ophthalmology. 2022 Mar 30.

Meyer J, Fry C, Turner A, Razavi H.

Background: Frequent intravitreal anti-VEGF injections are impractical for many Aboriginal patients with diabetic macular oedema (DMO). The longer acting intravitreal dexamethasone implant (DEX-implant) is approved for DMO but has not been assessed in an Aboriginal population.

Methods: This was a prospective, multicentre, randomized, single-masked, non-inferiority clinical trial. Aboriginal adults from Western Australia with DMO were randomized to receive 3-monthly DEX-implant, or monthly intravitreal bevacizumab. The primary outcome was the change in best corrected visual acuity (BCVA) at 12 months.

Results: The final endpoint was analysed for 24 DEX-implant and 28 bevacizumab injection eyes. Mean BCVA improved by 4.0 letters (-0.08 LogMAR) in the DEX-implant group and worsened by 5.5 letters (0.11 LogMAR) in the bevacizumab group. Before adjusting for cataract surgery, the upper bound of the two-sided 90% CI for the DEX-implant was 3.5 letters (0.07 LogMAR), which met non-inferiority criteria. The BCVA of remote participants who received the DEX-implant improved by 5.5 letters (0.11 LogMAR), compared to an 18.5 letter (0.37 LogMAR) decline for bevacizumab (P=0.04). The incidence of steroid-induced ocular hypertension for the DEX-implant was 33.3%.

Conclusions: Before adjusting for the effect of cataract surgery, the DEX-implant was non-inferior to bevacizumab for treating DMO in Aboriginal participants. In remote participants, the DEX-implant surpassed non-inferiority to achieve superior outcomes to bevacizumab. The incidence of steroid-induced hypertension was comparable to that reported in non-Aboriginal populations. We provide guidelines for the judicious use of DEX-implant among Aboriginal people, and a framework for performing ophthalmic clinical trials in Aboriginal communities. This article is protected by copyright. All rights reserved.

DOI: 10.1111/ceo.14079

Baseline retinal vascular bed area on ultra-wide field fluorescein angiography correlates with the anatomical outcome of diabetic macular oedema to ranibizumab therapy: two-year analysis of the DAVE Study.

Eye (London). 2022 Mar 24.

Fan W, Uji A, Wykoff CC, Brown DM, van Hemert J, Falavarjani KG, Wang K, Sadda SR, Ip M.

Purpose: To determine the relationship between baseline retinal non-perfusion area (NPA) and retinal vascular bed area (RVBA) on ultra-wide field fluorescein angiography (UWF FA) and long-term response to intravitreal ranibizumab therapy in diabetic macular oedema (DMO).

Methods: A post-hoc, 2-year observational case series. Baseline UWF FA images (Optos 200Tx) of 40 eyes from 29 patients with diabetes mellitus and treatment naïve DMO in the DAVE (NCT01552408) study were montaged and stereographically projected at the Doheny Image Reading Center to adjust for peripheral distortion. The retinal vasculature was automatically extracted to calculate RVBA. NPA was manually delineated by two masked certified graders. RVBA and NPA were computed in mm2 automatically by adjusting for peripheral distortion and then correlated with the severity of DMO.

Results: While global NPA at baseline was not correlated to retinal thickness measurements, baseline NPA in the superior retina was associated with the macular volume (MV) improvement (P = 0.022). Multivariate analysis revealed a smaller RVBA at baseline was correlated with a better MV outcome at two-year follow-up after adjusting for confounding factors (P = 0.049).

Conclusion: Eyes with smaller baseline RVBA appear to have a better long-term anatomic outcome of DMO.

DOI: 10.1038/s41433-021-01777-7

Fluctuations in central foveal thickness and association with vision outcomes with anti-VEGF therapy for nAMD: HARBOR post hoc analysis.

BMJ Open Ophthalmology. 2022 Mar 9

Sheth V, D’Rozario M, Gune S, Blotner S.

Objective: To evaluate correlations between variability in central foveal thickness (CFT) and vision with ranibizumab in a HARBOR post hoc analysis.

Methods and analysis: Patients with neovascular age-related macular degeneration (nAMD; N=1097) received monthly or as-needed (PRN) ranibizumab (0.5 or 2.0 mg) for 24 months. Fluctuation scores were used to assess CFT variability; every time CFT increased and then decreased (or vice versa), numeric value of the change was added to the score. Magnitude of change <50 µm was considered clinically insignificant and did not count towards the score. Fluctuation scores were grouped into quartiles. Least squares mean (LSM) changes in best-corrected visual acuity (BCVA) were plotted against fluctuation score quartiles for CFT, subretinal fluid (SRF) height, neurosensory retina and neurosensory retina + subretinal hyper-reflective material.

Results: Patients with lower fluctuations scores (quartiles 1-3) had greatest vision gains at month 24, with LSM changes from baseline of 9.0-10.8 and 8.7-10.6 letters in the monthly and PRN arms, respectively. Corresponding changes for quartile 4 were 6.7 and 6.5 letters, respectively. There were no differences between quartiles for association between fluctuations in SRF height and BCVA gains. There were inverse correlations between magnitude of fluctuations in neurosensory and inner retina thickness and BCVA gains for quartile 4 vs quartiles 1-3. Patients in quartiles 1 and 2 showed rapid, robust BCVA gains, whereas those in quartiles 3 and 4 had lesser responses.

Conclusions: Fluctuations in retinal thickening with ranibizumab may be associated with treatment response in patients with nAMD. TRIAL REGISTRATION NUMBER: NCT00891735.

DOI: 10.1136/bmjophth-2021-000957

FUTURE DIAGNOSIS AND MANAGEMENT TOOLS

LONGL-Net: temporal correlation structure guided deep learning model to predict longitudinal age-related macular degeneration severity.

PNAS Nexus. 2022 Mar 19

Ganjdanesh A, Zhang J, Chew EY, Ding Y, Huang H, Chen W.

Age-related macular degeneration (AMD) is the principal cause of blindness in developed countries, and its prevalence will increase to 288 million people in 2040. Therefore, automated grading and prediction methods can be highly beneficial for recognizing susceptible subjects to late-AMD and enabling clinicians to start preventive actions for them. Clinically, AMD severity is quantified by Color Fundus Photographs (CFP) of the retina, and many machine-learning-based methods are proposed for grading AMD severity. However, few models were developed to predict the longitudinal progression status, i.e. predicting future late-AMD risk based on the current CFP, which is more clinically interesting. In this paper, we propose a new deep-learning-based classification model (LONGL-Net) that can simultaneously grade the current CFP and predict the longitudinal outcome, i.e. whether the subject will be in late-AMD in the future time-point. We design a new temporal-correlation-structure-guided Generative Adversarial Network model that learns the interrelations of temporal changes in CFPs in consecutive time-points and provides interpretability for the classifier’s decisions by forecasting AMD symptoms in the future CFPs. We used about 30,000 CFP images from 4,628 participants in the Age-Related Eye Disease Study. Our classifier showed average 0.905 (95% CI: 0.886-0.922) AUC and 0.762 (95% CI: 0.733-0.792) accuracy on the 3-class classification problem of simultaneously grading current time-point’s AMD condition and predicting late AMD progression of subjects in the future time-point. We further validated our model on the UK Biobank dataset, where our model showed average 0.905 accuracy and 0.797 sensitivity in grading 300 CFP images.

DOI: 10.1093/pnasnexus/pgab003

REVIEW

Beyond the Glycaemic Control of Dapagliflozin: Microangiopathy and Non-classical Complications.

Diabetes Therapy. 2022 Mar 25

Bellido V, Martínez J, Calvo F, Villarroel A, Lecumberri E, Moreno J, Morillas C, Rodrigo S, Izarra A, Lecube A.

Dapagliflozin is a selective sodium-glucose cotransporter 2 inhibitor (SGLT2i) indicated for the treatment of type 2 diabetes mellitus (T2DM), heart failure (HF) with reduced ejection fraction (EF) and chronic kidney disease (CKD). In monotherapy or as an additive therapy, dapagliflozin aids glycaemic control, is associated with reductions in blood pressure and weight, and promotes a favourable lipid profile. In this review, we address the impact of dapagliflozin on cardiovascular risk factors and common microangiopathic complications such as kidney disease and retinopathy in patients with T2DM. Furthermore, we evaluate its potential beneficial effects on other less frequent complications of diabetes, such as macular oedema, cognitive impairment, non-alcoholic fatty liver disease and respiratory disorders during sleep. Moreover, the underuse of SGLT2i in clinical practice is discussed. Our goal is to help translate this evidence into clinical practice.

DOI: 10.1007/s13300-022-01237-9

FUTURE THERAPIES

Retinal Cell Transplantation, Biomaterials, and In Vitro Models for Developing Next-generation Therapies of Age-related Macular Degeneration.

Stem Cells Translational Medicine. 2022 Mar 31

Rizzolo LJ, Nasonkin IO, Adelman RA.

Retinal pigment epithelium (RPE) cells grown on a scaffold, an RPE patch, have potential to ameliorate visual impairment in a limited number of retinal degenerative conditions. This tissue-replacement therapy is suited for age-related macular degeneration (AMD), and related diseases. RPE cells must be transplanted before the disease reaches a point of no return, represented by the loss of photoreceptors. Photoreceptors are specialized, terminally differentiated neurosensory cells that must interact with RPE’s apical processes to be functional. Human photoreceptors are not known to regenerate. On the RPE’s basal side, the RPE transplant must induce the reformation of the choriocapillaris, thereby re-establishing the outer blood-retinal barrier. Because the scaffold is positioned between the RPE and choriocapillaris, it should ideally degrade and be replaced by the natural extracellular matrix that separates these tissues. Besides biodegradable, the scaffolds need to be nontoxic, thin enough to not affect the focal length of the eye, strong enough to survive the transplant procedure, yet flexible enough to conform to the curvature of the retina. The challenge is patients with progressing AMD treasure their remaining vision and fear that a risky surgical procedure will further degrade their vision. Accordingly, clinical trials only treat eyes with severe impairment that have few photoreceptors to interact with the transplanted patch. Although safety has been demonstrated, the cell-replacement mechanism and efficacy remain difficult to validate. This review covers the structure of the retina, the pathology of AMD, the limitations of cell therapy approaches, and the recent progress in developing retinal therapies using biomaterials.

DOI: 10.1093/stcltm/szac001