Diabetic Eye Disease

Horton MB, Brady CJ, Cavallerano J, Abramoff M, Barker G, Chiang MF, Crockett CH, Garg S, Karth P, Liu Y, Newman CD, Rathi S, Sheth V, Silva P, Stebbins K, Zimmer-Galler I. Practice Guidelines for Ocular Telehealth-Diabetic Retinopathy, Third Edition. Telemed J E Health 2020;26(4):495-543.Abstract
Contributors The following document and appendices represent the third edition of the . These guidelines were developed by the Diabetic Retinopathy Telehealth Practice Guidelines Working Group. This working group consisted of a large number of subject matter experts in clinical applications for telehealth in ophthalmology. The editorial committee consisted of Mark B. Horton, OD, MD, who served as working group chair and Christopher J. Brady, MD, MHS, and Jerry Cavallerano, OD, PhD, who served as cochairs. The writing committees were separated into seven different categories. They are as follows: 1.Clinical/operational: Jerry Cavallerano, OD, PhD (Chair), Gail Barker, PhD, MBA, Christopher J. Brady, MD, MHS, Yao Liu, MD, MS, Siddarth Rathi, MD, MBA, Veeral Sheth, MD, MBA, Paolo Silva, MD, and Ingrid Zimmer-Galler, MD. 2.Equipment: Veeral Sheth, MD (Chair), Mark B. Horton, OD, MD, Siddarth Rathi, MD, MBA, Paolo Silva, MD, and Kristen Stebbins, MSPH. 3.Quality assurance: Mark B. Horton, OD, MD (Chair), Seema Garg, MD, PhD, Yao Liu, MD, MS, and Ingrid Zimmer-Galler, MD. 4.Glaucoma: Yao Liu, MD, MS (Chair) and Siddarth Rathi, MD, MBA. 5.Retinopathy of prematurity: Christopher J. Brady, MD, MHS (Chair) and Ingrid Zimmer-Galler, MD. 6.Age-related macular degeneration: Christopher J. Brady, MD, MHS (Chair) and Ingrid Zimmer-Galler, MD. 7.Autonomous and computer assisted detection, classification and diagnosis of diabetic retinopathy: Michael Abramoff, MD, PhD (Chair), Michael F. Chiang, MD, and Paolo Silva, MD.
Ashraf M, Sampani K, AbdelAl O, Fleming A, Cavallerano J, Souka A, El Baha SM, Silva PS, Sun J, Aiello LP. Disparity of microaneurysm count between ultrawide field colour imaging and ultrawide field fluorescein angiography in eyes with diabetic retinopathy. Br J Ophthalmol 2020;104(12):1762-1767.Abstract
AIMS: To compare microaneurysm (MA) counts using ultrawide field colour images (UWF-CI) and ultrawide field fluorescein angiography (UWF-FA). METHODS: Retrospective study including patients with type 1 or 2 diabetes mellitus receiving UWF-FA and UWF-CI within 2 weeks. MAs were manually counted in individual Early Treatment Diabetic Retinopathy Study (ETDRS) and extended UWF zones. Fields with MAs ≥20 determined diabetic retinopathy (DR) severity (0 fields=mild, 1-3=moderate, ≥4=severe). UWF-FA and UWF-CI agreement was determined and UWF-CI DR severity sensitivity analysis adjusting for UWF-FA MA counts performed. RESULTS: In 193 patients (288 eyes), 2.4% had no DR, 29.9% mild non-proliferative DR (NPDR), 32.6% moderate (NPDR), 22.9% severe NPDR and 12.2% proliferative DR. UWF-FA MA counts were 3.5-fold higher (p<0.001) than UWF-CI counts overall, 3.2x-fold higher in ETDRS fields (p<0.001) and 5.3-fold higher in extended ETDRS fields (p<0.001) and higher in type 1 versus type 2 diabetes (p<0.001). In eyes with NPDR on UWF-CI (n=246), UWF-FA images had 1.6x-3.5x more fields with ≥20 MAs (p<0.001). Fair agreement existed between imaging modalities (k=0.221-0.416). In ETDRS fields, DR severity agreement increased from k=0.346 to 0.600 when dividing UWF-FA counts by a factor of 3, followed by rapid decline in agreement thereafter. Total UWF area agreement increased from k=0.317 to 0.565 with an adjustment factor of either 4 or 5. CONCLUSIONS: UWF-FA detects threefold to fivefold more MAs than UWF-CI and identifies 1.6-3.5-fold more fields affecting DR severity. Differences exist at all DR severity levels, thus limiting direct comparison between the modalities. However, correcting UWF-FA MA counts substantially improves DR severity agreement between the modalities.
Glassman AR, Baker CW, Beaulieu WT, Bressler NM, Punjabi OS, Stockdale CR, Wykoff CC, Jampol LM, Sun JK, Sun JK. Assessment of the DRCR Retina Network Approach to Management With Initial Observation for Eyes With Center-Involved Diabetic Macular Edema and Good Visual Acuity: A Secondary Analysis of a Randomized Clinical Trial. JAMA Ophthalmol 2020;Abstract
Importance: Among eyes with center-involved diabetic macular edema (CI-DME) and good visual acuity (VA), randomized clinical trial results showed no difference in VA loss between initial observation plus aflibercept only if VA decreased, initial focal/grid laser plus aflibercept only if VA decreased, or prompt aflibercept. Understanding the initial observation approach is relevant to patient management. Objective: To assess the DRCR Retina Network protocol-defined approach and outcomes of initial observation with aflibercept only if VA worsened. Design, Setting, and Participants: This was a post hoc secondary analyses of a randomized clinical trial of the DRCR Retina Network Protocol V that included 91 US and Canadian sites from November 2013 to September 2018. Participants were adults (n = 236) with type 1 or 2 diabetes, 1 study eye with CI-DME, and VA letter score at least 79 (Snellen equivalent, 20/25 or better) assigned to initial observation. Data were analyzed from March 2019 to November 2019. Interventions: Initial observation and follow-up with aflibercept only for VA loss of at least 10 letters from baseline at 1 visit or 5 to 9 letters at 2 consecutive visits. Follow-up occurred at 8 weeks and then every 16 weeks unless VA or optical coherence tomography central subfield thickness worsened. Main Outcomes and Measures: Whether individuals received aflibercept. Results: Among 236 eyes in 236 individuals (149 [63%] male; median age, 60 years [interquartile range, 53-67 years]) randomly assigned to initial observation, 80 (34%) were treated with aflibercept during 2 years of follow-up. At 2 years, the median VA letter score was 86.0 (interquartile range, 89.0-81.0; median Snellen equivalent, 20/20 [20/16-20/25]). Receipt of aflibercept was more likely in eyes with baseline central subfield thickness at least 300 μm (Zeiss-Stratus equivalent) vs less than 300 μm (45% vs 26%; hazard ratio [HR], 1.98 [95% CI, 1.26-3.13], continuous P = .005), moderately severe nonproliferative diabetic retinopathy (Early Treatment Diabetic Retinopathy Study retinopathy severity level 47) and above vs moderate nonproliferative diabetic retinopathy (retinopathy severity level 43) and below (51% vs 27%; HR, 2.22 [95% CI, 1.42-3.47], ordinal P < .001), and among participants whose nonstudy eye received DME treatment within 4 months of randomization vs not (52% vs 25%; HR, 2.55 [95% CI, 1.64-3.99], P < .001). Conclusions and Relevance: Most eyes managed with initial observation plus aflibercept only if VA worsened maintained good vision at 2 years and did not require aflibercept for VA loss. However, the eyes in the trial were approximately twice as likely to receive aflibercept for VA loss if they had greater baseline central subfield thickness, worse diabetic retinopathy severity level, or a nonstudy eye receiving treatment for DME. Trial Registration: ClinicalTrials.gov Identifier: NCT01909791.
Glassman AR, Beaulieu WT, Stockdale CR, Beck RW, Bressler NM, Labriola LT, Melia M, Oliver K, Sun JK. Effect of telephone calls from a centralized coordinating center on participant retention in a randomized clinical trial. Clin Trials 2020;:1740774519894229.Abstract
BACKGROUND/AIMS: In clinical trials, participant retention is critical to reduce bias and maintain statistical power for hypothesis testing. Within a multi-center clinical trial of diabetic retinopathy, we investigated whether regular phone calls to participants from the coordinating center improved long-term participant retention. METHODS: Among 305 adults in the Diabetic Retinopathy Clinical Research Retina Network Protocol S randomized trial, 152 participants were randomly assigned to receive phone calls at baseline, 6 months, and annually through 3 years (annual contact group) while 153 participants were assigned to receive a phone call at baseline only (baseline contact group). All participants could be contacted if visits were missed. The main outcomes were visit completion, excluding deaths, at 2 years (the primary outcome time point) and at 5 years (the final time point). RESULTS: At baseline, 77% (117 of 152) of participants in the annual contact group and 76% (116 of 153) in the baseline contact group were successfully contacted. Among participants in the annual contact group active at each annual visit (i.e. not dropped from the study or deceased), 85% (125 of 147), 79% (108 of 136), and 88% (110 of 125) were contacted successfully by telephone around the time of the 1-, 2-, and 3-year visits, respectively. In the annual and baseline contact groups, completion rates for the 2-year primary outcome visit were 88% (129 of 147) versus 87% (125 of 144), respectively, with a risk ratio of 1.01 (95% confidence interval: 0.93-1.10,  = .81). At 5 years, the final study visit, participant completion rates were 67% (96 of 144) versus 66% (88 of 133) with a risk ratio of 1.01 (95% confidence interval = 0.85-1.19,  = .93). At 2 years, the completion rate of participants successfully contacted at baseline was 89% (202 of 226) versus 80% (52 of 65) among those not contacted successfully (risk ratio = 1.12, 95% confidence interval = 0.98-1.27,  = .09); at 5 years, the completion percentages by baseline contact success were 69% (148 of 213) versus 56% (36 of 64; risk ratio = 1.24, 95% confidence interval = 0.98-1.56,  = .08). CONCLUSION: Regular phone calls from the coordinating center to participants during follow-up in this randomized clinical trial did not improve long-term participant retention.
Bressler NM, Beaulieu WT, Bressler SB, Glassman AR, Melia MB, Jampol LM, Jhaveri CD, Salehi-Had H, Velez G, Sun JK, Sun JK. ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY AND RISK OF TRACTION RETINAL DETACHMENT IN EYES WITH PROLIFERATIVE DIABETIC RETINOPATHY: Pooled Analysis of Five DRCR Retina Network Randomized Clinical Trials. Retina 2020;40(6):1021-1028.Abstract
PURPOSE: To investigate whether anti-vascular endothelial growth factor (anti-VEGF) for diabetic macular edema or proliferative diabetic retinopathy (PDR) increases the risk of traction retinal detachment (TRD) among eyes with PDR. METHODS: Pooled analysis of PDR eyes from Protocols I, J, N, S, or T with Early Treatment Diabetic Retinopathy Study level ≥61 (prompt vitrectomy was not planned) randomly assigned to the control group (laser photocoagulation, sham, or intravitreal saline; 396 eyes) or anti-VEGF (487 eyes). The primary outcome was investigator-identified TRD within 1 year of randomization. RESULTS: The 1-year cumulative probability of TRD was 6.8% (95% confidence interval: 4.6%-9.9%, 25 events) in control-group eyes and 4.8% (95% confidence interval: 3.2%-7.3%, 22 events) in anti-VEGF group eyes (hazard ratio = 0.95 [95% confidence interval: 0.54-1.66, P = 0.86]). The cumulative probability of vitrectomy for TRD was 4.4% (16 events) in control-group eyes and 2.2% (9 events) in anti-VEGF group eyes (P = 0.19). Percentage with TRD and vitrectomy for TRD were similar within strata of diabetic retinopathy severity. CONCLUSION: These findings do not support the hypothesis that anti-VEGF therapy for diabetic macular edema or PDR increases the risk of TRD among eyes with PDR similar to those enrolled in five DRCR Retina Network protocols for which prompt vitrectomy was not planned.
Cui Y, Zhu Y, Wang JC, Lu Y, Zeng R, Katz R, Wu DM, Vavvas DG, Husain D, Miller JW, Kim LA, Miller JB. Imaging Artifacts and Segmentation Errors With Wide-Field Swept-Source Optical Coherence Tomography Angiography in Diabetic Retinopathy. Transl Vis Sci Technol 2019;8(6):18.Abstract
Purpose: To analyze imaging artifacts and segmentation errors with wide-field swept-source optical coherence tomography angiography (SS-OCTA) in diabetic retinopathy (DR). Methods: We conducted a prospective, observational study at Massachusetts Eye and Ear from December 2018 to March 2019. Proliferative diabetic retinopathy (PDR), nonproliferative diabetic retinopathy (NPDR), diabetic patients with no diabetic retinopathy (DR), and healthy control eyes were included. All patients were imaged with a SS-OCTA and the Montage Angio (15 × 9 mm) was used for analysis. Images were independently evaluated by two graders using the motion artifact score (MAS). All statistical analyses were performed using SPSS 25.0 and R software. Results: One hundred thirty-six eyes in 98 participants with the montage image were included in the study. Patients with more severe stages of DR had higher MAS by trend test analysis ( < 0.05). The occurrence of segmentation error was 0% in the healthy group, 10.53% in the no DR group, 10.00% in the NPDR group, and 50% in the PDR group. Multivariate regression analysis showed that the severity of DR and dry eye were the major factors affecting MAS ( < 0.05). There were some modifiable artifacts that could be corrected to improve image quality. Conclusions: Wide field SS-OCTA assesses retinal microvascular changes by noninvasive techniques, yet distinguishing real alterations from artifacts is paramount to accurate interpretations. DR severity and dry eye correlated with MAS. Translational Relevance: Understanding contributing factors and methods to reduce artifacts is critical to routine use and clinical trial with wide-field SS-OCTA.
Muqit MMK, Kourgialis N, Jackson-deGraffenried M, Talukder Z, Khetran ER, Rahman A, Chan WO, Chowdury FA, Nag D, Ahmad J, Friedman DS. Trends in Diabetic Retinopathy, Visual Acuity, and Treatment Outcomes for Patients Living With Diabetes in a Fundus Photograph-Based Diabetic Retinopathy Screening Program in Bangladesh. JAMA Netw Open 2019;2(11):e1916285.Abstract
Importance: Diabetic retinopathy (DR) is the leading cause of low vision among working-age adults. An estimated 6.9 million people in Bangladesh were living with diabetes in 2017, which is projected to increase to more than 10 million people in 2025. Currently, no standardized and/or large-scale DR screening program exists in Bangladesh. Objective: To develop a novel fundus photograph-based eye screening model for early detection of DR to prevent vision loss in Bangladeshi individuals with diabetes. Design, Setting, and Participants: In this cross-sectional study, 49 264 patients with diabetes underwent opportunistic eye screening at 2 eye hospitals and 1 diabetic hospital in Bangladesh between June 1, 2010, and September 30, 2017. The data set was analyzed from April 8 to December 30, 2018. Technicians were trained to obtain 2-field digital fundus photographs and to grade each according to a standardized DR severity scale. Each patient was counseled and triaged for treatment using defined DR referral criteria. Main Outcomes and Measures: Primary DR grading outcomes, visual acuity, and treatment outcomes. Results: A total of 49 264 patients (54.3% male; mean [SD] age, 50.8 [12.3] years) underwent DR screening during a 7-year period. The DR prevalence rate across all 3 sites was 33% (95% CI, 33%-33%). Prevalence rates varied by center (Chittagong, 64.6% [95% CI, 64.0%-65.0%]; Dhaka, 39.8% [95% CI, 39.0%-41.0%]; and Feni, 13.0% [95% CI, 13.0%-14.0%]). Across all age groups, male patients were at higher risk of prevalent DR than female patients (odds ratio, 1.99; 95% CI, 1.90-2.07). The prevalence was 3.9% for preproliferative DR, 7.8% for proliferative DR, and 19.2% for maculopathy. Individuals with DR had significantly worse visual acuity than those with no DR (best-corrected visual acuity, 0.35 vs 0.21 logMAR; P < .001). The rate of moderate visual impairment was 12.2%, and the rate of blindness was 2.5%. Primary treatments included laser photocoagulation (n = 1637), intravitreal injection (n = 1440), and vitrectomy (n = 309). Conclusions and Relevance: Screening Bangladeshi individuals known to have diabetes using fundus photography identified large numbers of patients with sight-threatening proliferative DR, maculopathy, and visual impairment or blindness. Expansion of eye screening services in Bangladesh is warranted as part of a national government eye care and diabetes health policy.
Wang Y, Lin Z, Wen L, Rong SS, Ding XX, Li D, Feng KM, Wang FH, Liang YB, Zhai G. Rationale, Design, Methodology and Baseline Data of Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT). Ophthalmic Epidemiol 2019;:1-10.Abstract
: To describe the rationale, design, methodology and baseline characteristics of Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT), a community-based prospective cohort study in patients with type 2 diabetes mellitus (T2DM) living in northeast China.: Patients with T2DM, aged 30 years and above from communities of Fushun city, Liaoning province, China, were recruited. The presence and severity of the diabetic retinopathy (DR) were determined by a modified Early Treatment Diabetic Retinopathy Study (ETDRS) retinopathy scale of 6 fields fundus photographs. Detailed ocular examinations and questionnaires were collated, in addition to blood and urine sample collection.: Of the 2224 subjects eligible for the FS-DIRECT, 2033 (91.4%) participated in the study. The majority of participants were female (58.9%), the average age was 62.1 ± 9.1 years. The overall prevalence rates of DR, non-proliferative DR, proliferative DR, diabetic macular edema, and vision-threatening retinopathy were 44.3%, 40.0%, 4.3%, 15.2%, and 12.3%, respectively. Compared to the patients without DR, patients with DR had lower income, an earlier onset of diabetes, a longer duration of diabetes, higher proportion of insulin use, higher fasting plasma glucose, HbA1c, systolic blood pressure, total cholesterol and high density lipoprotein, as well as a higher level of urine protein (all < .05).: The baseline data of FS-DIRECT showed a high prevalence of DR in a community of northeast China. Further investigation will provide key information about the risk factors, impact, and trends of DR in this region.
McKay TB, Priyadarsini S, Karamichos D. Mechanisms of Collagen Crosslinking in Diabetes and Keratoconus. Cells 2019;8(10)Abstract
Collagen crosslinking provides the mechanical strength required for physiological maintenance of the extracellular matrix in most tissues in the human body, including the cornea. Aging and diabetes mellitus (DM) are processes that are both associated with increased collagen crosslinking that leads to increased corneal rigidity. By contrast, keratoconus (KC) is a corneal thinning disease associated with decreased mechanical stiffness leading to ectasia of the central cornea. Studies have suggested that crosslinking mediated by reactive advanced glycation end products during DM may protect the cornea from KC development. Parallel to this hypothesis, riboflavin-mediated photoreactive corneal crosslinking has been proposed as a therapeutic option to halt the progression of corneal thinning by inducing intra- and intermolecular crosslink formation within the collagen fibrils of the stroma, leading to stabilization of the disease. Here, we review the pathobiology of DM and KC in the context of corneal structure, the epidemiology behind the inverse correlation of DM and KC development, and the chemical mechanisms of lysyl oxidase-mediated crosslinking, advanced glycation end product-mediated crosslinking, and photoreactive riboflavin-mediated corneal crosslinking. The goal of this review is to define the biological and chemical pathways important in physiological and pathological processes related to collagen crosslinking in DM and KC.
Hutton DW, Stein JD, Glassman AR, Bressler NM, Jampol LM, Sun JK, Sun JK. Five-Year Cost-effectiveness of Intravitreous Ranibizumab Therapy vs Panretinal Photocoagulation for Treating Proliferative Diabetic Retinopathy: A Secondary Analysis of a Randomized Clinical Trial. JAMA Ophthalmol 2019;:1-9.Abstract
Importance: The DRCR Retina Network Protocol S randomized clinical trial suggested that the mean visual acuity of eyes with proliferative diabetic retinopathy (PDR) treated with ranibizumab is not worse at 5 years than that of eyes treated with panretinal photocoagulation (PRP). Moreover, the ranibizumab group had fewer new cases of diabetic macular edema (DME) with vision loss or vitrectomy but had 4 times the number of injections and 3 times the number of visits. Although 2-year cost-effectiveness results of Protocol S were previously identified, incorporating 5-year data from Protocol S could alter the longer-term cost-effectiveness of the treatment strategies from the perspective of the health care system. Objective: To evaluate 5- and 10-year cost-effectiveness of therapy with ranibizumab, 0.5 mg, compared with PRP for treating PDR. Design, Setting, and Participants: A preplanned secondary analysis of the Protocol S randomized clinical trial using efficacy, safety, and resource utilization data through 5 years of follow-up for 213 adults diagnosed with PDR and simulating results through 10 years. Interventions: Intravitreous ranibizumab, 0.5 mg, at baseline and as frequently as every 4 weeks based on a structured retreatment protocol vs PRP at baseline for PDR; eyes in both groups could receive ranibizumab for concomitant DME with vision loss. Main Outcomes and Measures: Incremental cost-effectiveness ratios (ICERs) of ranibizumab therapy compared with PRP were evaluated for those with and without center-involved DME (CI-DME) and vision loss (Snellen equivalent, 20/32 or worse) at baseline. Results: The study included 213 adults with a mean (SD) age of 53 (12) years, of whom 92 (43%) were women and 155 (73%) were white. The ICER of the ranibizumab group compared with PRP for patients without CI-DME at baseline was $582 268 per quality-adjusted life-year (QALY) at 5 years and $742 202/QALY at 10 years. For patients with baseline CI-DME, ICERs were $65 576/QALY at 5 years and $63 930/QALY at 10 years. Conclusions and Relevance: This study suggests that during 5 to 10 years of treatment, ranibizumab, 0.5 mg, as given in the studied trial compared with PRP may be within the frequently cited range considered cost-effective in the United States for eyes presenting with PDR and vision-impairing CI-DME, but not for those with PDR but without vision-impairing CI-DME. Substantial reductions in anti-vascular endothelial growth factor cost may make the ranibizumab therapy cost-effective within this range even for patients without baseline CI-DME. Trial Registration: ClinicalTrials.gov identifier: NCT01489189.
Sun JK, Jampol LM. The Diabetic Retinopathy Clinical Research Network (DRCR.net) and Its Contributions to the Treatment of Diabetic Retinopathy. Ophthalmic Res 2019;:1-6.Abstract
Over the past two decades, the Diabetic Retinopathy Clinical Research Network (now known as the DRCR Retina Network) has contributed to multiple and substantial advances in the clinical care of diabetic eye disease. Network studies helped establish anti-vascular endothelial growth factor (VEGF) agents as an effective alternative to panretinal photocoagulation for eyes with proliferative diabetic retinopathy (PDR) and as first-line therapy for eyes with visual impairment for diabetic macular edema (DME), defined treatment algorithms for the use of intravitreal medications in these conditions, and provided critical data to understand how to better evaluate the diabetic eye using optical coherence tomography and other imaging modalities. Ongoing DRCR.net studies will address whether anti-VEGF therapy is effective at preventing vision-threatening complications in eyes with severe non-proliferative diabetic retinopathy, if photobiomodulation has a beneficial effect in eyes with DME, and whether initiation of DME treatment with bevacizumab and rescue with aflibercept can provide visual outcomes as good as those achieved with aflibercept alone. Future plans for the Network also include the expansion into non-diabetic eye disease in areas such as age-related macular degeneration.
Busch C, Fraser-Bell S, Iglicki M, Lupidi M, Couturier A, Chaikitmongkol V, Giancipoli E, Rodríguez-Valdés PJ, Gabrielle P-H, Laíns I, Santos AR, Cebeci Z, Amphornphruet A, Degenhardt V, Unterlauft J-D, Cagini C, Mané-Tauty V, Ricci GD'A, Hindi I, Agrawal K, Chhablani J, Loewenstein A, Zur D, Rehak M, Rehak M. Real-world outcomes of non-responding diabetic macular edema treated with continued anti-VEGF therapy versus early switch to dexamethasone implant: 2-year results. Acta Diabetol 2019;56(12):1341-1350.Abstract
AIMS: To provide 2-year follow-up data on eyes with diabetic macular edema (DME) that were non-responsive after three initial anti-vascular endothelial growth factor (VEGF) injections, comparing functional and anatomical outcomes under continued anti-VEGF therapy versus dexamethasone (DEX) implant. METHODS: Multicenter, retrospective chart review comparing eyes with treatment-naïve DME and a suboptimal response to a loading phase of anti-VEGF therapy (3 injections given monthly) which were then treated with (a) further anti-VEGF (n = 72) or (b) initially switched to DEX implant (n = 38). Main outcome measures were change in visual acuity (VA) and central subfield thickness (CST) from the end of the loading phase to 24 months. RESULTS: In 79% of the 12-month study population (87/110 eyes), 24-month data were available. One quarter of eyes in each group switched treatments during the second year. Eyes that were switched early to DEX implant maintained the functional and anatomical improvements at 24 months which were seen in the first year (from month 3: + 8.9 letters, - 214 µm). Eyes that were switched from anti-VEGF therapy to steroids in the second year improved VA and reduced CST at 24 months (from month 12: + 6.8 letters, p = 0.023; - 226 µm, p = 0.004). In eyes continued on anti-VEGF therapy, VA and CST were stable at 24 months (from month 3: + 2.8 letters, p = 0.254; - 24 µm, p = 0.243). Eyes that were non-responsive to anti-VEGF therapy for 12 months had similar chances to experience a VA gain from further therapy as eyes that were non-responsive for 3 months only (23.8 vs. 31.0%, p = 0.344). CONCLUSIONS: The beneficial effect of an early switch to DEX implant in DME non-responders seen at month 12 was maintained during the second year. A later switch from anti-VEGF to steroids still provided significant improvement. Eyes continued on anti-VEGF over a period of 24 months maintained vision. A quarter of eyes, which had not improved vision at 12 months, exhibited a delayed response to treatment.
Yokomizo H, Maeda Y, Park K, Clermont AC, Hernandez SL, Fickweiler W, Li Q, Wang C-H, Paniagua SM, Simao F, Ishikado A, Sun B, Wu I-H, Katagiri S, Pober DM, Tinsley LJ, Avery RL, Feener EP, Kern TS, Keenan HA, Aiello LP, Sun JK, King GL. Retinol binding protein 3 is increased in the retina of patients with diabetes resistant to diabetic retinopathy. Sci Transl Med 2019;11(499)Abstract
The Joslin Medalist Study characterized people affected with type 1 diabetes for 50 years or longer. More than 35% of these individuals exhibit no to mild diabetic retinopathy (DR), independent of glycemic control, suggesting the presence of endogenous protective factors against DR in a subpopulation of patients. Proteomic analysis of retina and vitreous identified retinol binding protein 3 (RBP3), a retinol transport protein secreted mainly by the photoreceptors, as elevated in Medalist patients protected from advanced DR. Mass spectrometry and protein expression analysis identified an inverse association between vitreous RBP3 concentration and DR severity. Intravitreal injection and photoreceptor-specific overexpression of RBP3 in rodents inhibited the detrimental effects of vascular endothelial growth factor (VEGF). Mechanistically, our results showed that recombinant RBP3 exerted the therapeutic effects by binding and inhibiting VEGF receptor tyrosine phosphorylation. In addition, by binding to glucose transporter 1 (GLUT1) and decreasing glucose uptake, RBP3 blocked the detrimental effects of hyperglycemia in inducing inflammatory cytokines in retinal endothelial and Müller cells. Elevated expression of photoreceptor-secreted RBP3 may have a role in protection against the progression of DR due to hyperglycemia by inhibiting glucose uptake via GLUT1 and decreasing the expression of inflammatory cytokines and VEGF.