Treatment of neovascular age-related macular degeneration in patients with diabetes

Abstract

The number of patients with type 2 diabetes continues to rise; an anticipated 300 million people will be affected by 2025. The immense social and economic burden of the condition is exacerbated by the initial asymptomatic nature of type 2 diabetes, resulting in a high prevalence of micro-and macrovascular complications at presentation. Diabetic retinopathy, one of the potential microvascular complications associated with diabetes, and neovascular age-related macular degeneration (AMD) are the two most frequent retinal degenerative diseases, and are responsible for the majority of blindness due to retinal disease. Both conditions predominantly affect the central macula, and are associated with the presence of retinal edema and an aggressive inflammatory repair process that accelerates disease progression. The associated retinal edema and the inflammatory repair process are directly involved in the breakdown of the blood-retinal barrier (BRB). Yet, the underlying alterations to the BRB caused by the diseases are very different. The coexistence of the two conditions appears to be relatively uncommon, suggesting that diabetes may even protect patients from developing neovascular AMD. However, it is thought that the inflammatory repair responses associated with diabetic retinopathy and neovascular AMD may be cumulative and, in patients affected by both, could result in chronic diffuse cystoid edema. Treatment considerations in such patients should, therefore, include the role of retinal edema and the increased susceptibility of patients with diabetes to potential systemic side effects associated with agents administered repeatedly for neovascular AMD treatment.

Epidemiological Association Between Systemic Diseases and Age-Related Macular Degeneration: The Korea National Health and Nutrition Examination Survey 2008–2011

“…As a result, we obtained multivariate models that included the presence of DM as a negatively associated factor with any AMD as well as late AMD, consistent with results of previous reports. 10,11,[18][19][20][21] Another notable finding in this study was a correlation between liver cancer with any AMD (OR, 4.32) and late AMD (OR, 12.51). A recent study reported a higher prevalence of AMD in patients who underwent liver transplantation (64.6%) than in a general population of similar ethnicity and age (37.1%).…”

“…19 Additionally, the damaged inner blood-retinal barrier observed in patients with DR induces a signal that upregulates the transport function of the RPE 25 and possibly delays deposition of drusen. 10 In this study, the presence of DR was associated with a decreased risk of any AMD in addition to the effect of DM itself. One possible explanation for this observation is that the presence of DR may indicate advanced ocular diabetic changes and, thus, could have enhanced the mechanisms described above.…”

“…Although previous studies have reported a positive correlation 8,15 or an insignificant association, 3,16,17 several researchers have described the uncommon coexistence of advanced AMD and DM or DR. 10,11,18,19 The 10-year incidence of neovascular AMD was lower in patients with newly diagnosed type 2 DM than in control subjects, 20 and the prevalence of neovascular AMD also was lower in patients with DR than in the general population. 19 The prevalence of neovascular AMD was much lower in those who received retinal laser photocoagulation to treat DR. 19 The prevalence of early AMD also was significantly lower in diabetic patients (2.51%) than in the general population (11%).…”

“…6,7 Epidemiological studies have reported hypertension, some cardiovascular diseases, and diabetes mellitus (DM) to be associated with increased AMD prevalence [7][8][9] However, other studies have shown inconsistent results for these diseases, 4,10 and have even reported an inverse association of DM with AMD. 11 The association of other systemic diseases with AMD remains undisclosed due to insufficient data.…”

Modulation of three key innate immune pathways for the most common retinal degenerative diseases

“…The vascular network not only forms in an unregulated manner, but also becomes leaky. New vessel formation is driven by the angiogenic factor vascular endothelial growth factor (VEGF), and hence, both diseases are treated with intravitreal injections of VEGF inhibitors; however, treatment success is not guaranteed (Cummings & Cunha‐Vaz, ). Moreover, no treatment options are currently available for patients suffering from GA. Another group of blinding diseases lacking established therapeutic options are inherited retinal degenerations, such as retinitis pigmentosa (RP).…”