High-Risk Diabetic Maculopathy: Features and Management

*Maya G. Pandova*

### **Abstract**

A substantial group of patients with diabetic macular edema in our clinical practice is at high risk for profound and irreversible vision deterioration. Early identification of modifiable factors with long-term negative impact and their management, close monitoring and timely adjustments in the treatment can significantly reduce the probability of visual disability in the individual patient. This approach can also provide important guidelines for proactive decision making in order to avoid the risk of suboptimal response and unsatisfactory outcome.

**Keywords:** Retinal symptoms and signs, systemic risk factors, treatment options, management stages

#### **1. Introduction**

The introduction of intravitreal pharmacotherapy dramatically improved the visual prognosis of the patients with diabetic macular edema (DME). However, the pivotal randomized clinical trials demonstrated that a sizable proportion of the eyes remained with disabling visual acuity despite intensive treatment and vigorous monitoring for 2 years [1]. Moreover, after transition to standard clinical care for the next 3 years, the visual acuity worsened even in patients with significant vision gain [2]. Real-world studies on DME management from Europe, USA, Japan and Australia reveal significant differences in the registration, national policies and restrictions for the use of the medications. A common issue is a tremendous pressure on the ophthalmic care providers to reduce the cost of visits and treatment. This invariably has resulted in visual outcomes that were meaningfully inferior to those achieved in randomized controlled trials [3–8].

These data suggest that a substantial group of patients with diabetic macular edema in our clinical practice is at high risk for profound and irreversible vision deterioration. Early identification of modifiable factors with long-term negative impact and their management, close monitoring and timely adjustments in the treatment can significantly reduce the probability of visual disability in the individual patient. Such a systematic approach can also provide important guidelines for proactive decision making in avoiding the risk of suboptimal response and unsatisfactory outcome.

#### **2. Low visual acuity at baseline**

Post hoc analysis of the best-corrected visual acuity (BCVA) achieved in DRCR. net Protocol T randomized clinical trial after anti-VEGF treatment [1] demonstrated that 96–100% of eyes enrolled in the trial with BCVA 20/32 to 20/40 retained high vision after 6 months even in the presence of persistent edema. A small

proportion - 8% of these eyes - deteriorated below 20/40 at the end of the first year and further 5–8% worsened after 2 years, and only if the edema was persistent. The outcome in eyes with baseline BCVA 20/50 to 20/320 was far less – through the 24th week 21–41% of them failed to improve over 20/50, and the results were worse if the edema was persistent – 31–51% of them had BCVA less than 20/40. By the end of the first year 11–30% of these eyes were still seeing below 20/40 and the outcome was worse if the edema was persistent – 33–46% remained in the low vision group. After 2 years of anti-VEGF treatment 17–25% of these eyes did not improve over 20/50 and their proportion reached 46% in eyes with persistent edema. Standard clinical care in the next three years resulted in vision deterioration by at least one Snellen line (4.8 letters) in the whole cohort and the proportion of eyes with BCVA less than 20/40 increased from 16% at the end of the second year to 27% [2]. The overall impression from the clinical trials and real-life practice is that significant vision gain is achievable even in eyes with low baseline vision at relatively low risk of severe vision loss, however it requires intensive treatment and the long-term outcome is often unstable. In contrast, eyes with higher visual acuity at baseline have much better chance to retain it in the next 2 and 5- year interval with appropriate management.
