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.

Guidelines on Diabetic Eye Care: The International Council of Ophthalmology Recommendations for Screening, Follow-up, Referral, and Treatment Based on Resource Settings

Diabetes mellitus (DM) is a global epidemic and affects populations in both developing and developed countries, with differing health care and resource levels. Diabetic retinopathy (DR) is a major complication of DM and a leading cause of vision loss in working middle-aged adults. Vision loss from DR can be prevented with broad-level public health strategies, but these need to be tailored to a country's and population's resource setting. Designing DR screening programs, with appropriate and timely referral to facilities with trained eye care professionals, and using cost-effective treatment for vision-threatening levels of DR can prevent vision loss. The International Council of Ophthalmology Guidelines for Diabetic Eye Care 2017 summarize and offer a comprehensive guide for DR screening, referral and follow-up schedules for DR, and appropriate management of vision-threatening DR, including diabetic macular edema (DME) and proliferative DR, for countries with high- and low- or intermediate-resource settings. The guidelines include updated evidence on screening and referral criteria, the minimum requirements for a screening vision and retinal examination, follow-up care, and management of DR and DME, including laser photocoagulation and appropriate use of intravitreal anti-vascular endothelial growth factor inhibitors and, in specific situations, intravitreal corticosteroids. Recommendations for management of DR in patients during pregnancy and with concomitant cataract also are included. The guidelines offer suggestions for monitoring outcomes and indicators of success at a population level.

Evidence-based review of diabetic macular edema management: Consensus statement on Indian treatment guidelines

The purpose of the study was to review the current evidence and design a diabetic macular edema (DME) management guideline specific for India. The published DME guidelines from different organizations and publications were weighed against the practice trends in India. This included the recently approved drugs. DME management consisted of control of diabetes and other associated systemic conditions, such as hypertension and hyperlipidemia, and specific therapy to reduce macular edema. Quantification of macular edema is precisely made with the optical coherence tomography and treatment options include retinal laser, intravitreal anti-vascular endothelial growth factors (VEGF), and implantable dexamethasone. Specific use of these modalities depends on the presenting vision and extent of macular involvement. Invariable eyes with center-involving macular edema benefit from intravitreal anti-VEGF or dexamethasone implant therapy, and eyes with macular edema not involving the macula center benefit from retinal laser. The results are illustrated with adequate case studies and frequently asked questions. This guideline prepared on the current published evidence is meant as a guideline for the treating physicians.

Initiation of intravitreal aflibercept injection treatment in patients with diabetic macular edema: a review of VIVID-DME and VISTA-DME data

Background

Diabetic macular edema (DME) shows a gradual and sustained functional and morphologic response to anti-vascular endothelial growth factor (VEGF) drugs, but the optimal schedule for initiation of anti-VEGF therapy is not known. This study evaluates the treatment response behavior of DME in the Phase 3 trials of intravitreal aflibercept, with 5 initial intravitreal aflibercept injections (IAI), 2 mg every 4 weeks (2q4), in the upload phase.

Methods

This post hoc pooled analysis of the VISTA-DME (NCT01363440) and VIVID-DME (NCT01331681) trials evaluated the change in best-corrected visual acuity (BCVA) and central retinal thickness (CRT) during the upload phase, using pooled data from both IAI treatment groups [2q4 and 2 mg every 8 weeks (2q8)]. The mean visit-to-visit change in BCVA and CRT, and the respective rate of gainers and losers was calculated for each successive visit. A secondary analysis compared the visit-to-visit change in BCVA between the 2q4 and 2q8 treatment arms during the upload period and the first year treatment period.

Results

The majority of eyes showed a continuing improvement of BCVA after the first IAI. The proportions of eyes gaining BCVA (≥5 letters) at each visit compared with the previous visit during the IAI 2q4 upload phase were 60 (4-weeks), 19 (8-weeks), 16 (12-weeks), 15 (16-weeks), and 14 % (20-weeks). In contrast, the proportions of eyes losing BCVA (≥5 letters) were 3 (4-weeks), 7 (8-weeks), 7 (12-weeks), 9 (16-weeks), and 8 % (20-weeks), respectively. The odds of BCVA (≥5 letters) gain/loss exceeded 1.7 at each visit (range 1.7–20). Overall, the proportion of patients with BCVA gain ≥5 letters at week 20 (compared with baseline) was 76 and 80 % in the 2q4 and 2q8 groups, respectively. The proportions of eyes showing a visit-to-visit decrease in CRT of ≥30 µm during the first 5 IAI were 77 (4-weeks), 27 (8-weeks), 21 (12-weeks), 17 (16-weeks), and 12 % (20-weeks). In the secondary analysis, the BCVA outcomes were similar for the 2q8 and 2q4 treatment arms.

Conclusions

The data presented here are consistent with continual functional and anatomic improvement following the fourth and fifth initial 2q4 injections, suggesting that an intensive and sufficiently long upload may be beneficial.

Trial registration VIVID-DME: Clinicaltrials.gov: NCT01331681; VISTA-DME: Clinicaltrials.gov: NCT01363440