Age-Related Macular Degeneration

Question 1

What is Age-Related Macular Degeneration?

Answer 1

• Chronic disease that destroys retina (specifically the macula)
• Normally doesn’t cause total blindness (asymptomatic)
• leading cause of irreversible vision impairment in US and developed nations

Question 2

What two factors affect the prevalence of ARMD?

Answer 2

• Age: prevalence higher in geriatric pop.

- Ethnicity: advanced ARMD (dry and neovascular) is more common in whites than blacks

Question 3

What are the risk factors associated with ARMD?

Answer 3

advancing age, ethnicity (higher risk in Northern European ancestry), cigarette smoking (doubles risk)

Question 4

What are the two types of ARMD?

Answer 4

• Dry (atrophic) ARMD: account for 90% of ARMD cases

- Wet(exudative/neovascular) ARMD: accounts for 90% of severe vision loss due to ARMD

Question 5

Describe the characteristics (pathophysiology) of Dry ARMD

Answer 5

presence of one or more of the following:

• Drusen: yellow deposits of lipids and proteins
• RPE (Retinal pigment epithelium) abnormalities
• Atrophy of RPE and choriocapillaris

Question 6

What are the characteristics (pathophysiology) of Wet (exudative/neovascular) ARMD?

Answer 6

hypoxic choriocapillary blood vessels–>increased VEFG–>blood vessel growth

• new vessel are fragile and leak blood and fluid–>raising of the macula
• subsequent scarring at macula (disciform scar*)
• potential rapid loss of central vision

Question 7

For pharmacological intervention, Dry ARMD is classified as either ____ or ______.

Answer 7

• Early

- Intermediate

Question 8

What pharmacological treatments are available for early ARMD (Dry)

Answer 8

There is currently no evidence to support use of vitamin and mineral supplementation in EARLY dry ARMD

Question 9

What pharmacological treatment are available for intermediate ARMD (Dry)

Answer 9

Vitamin and mineral supplementation to reduce progression of disease

• Vitamin C (1.1-0.5 g/day); vitamin E (50-100 IU/day); Beta-Carotene (100-300 mg/day)
• Mineral supplementation: zinc oxide, cupric oxide, and selenium
• Combination of vitamins and minerals provide max protection

Question 10

What pharmacological interventions can be used for WET ARMD?

Answer 10

• VEGF inhibitors (Ranibizumab, Aflibercept, Brolucizumab, Pegaptanib)
• Verteporfin

Question 11

What are the characteristics of Pegaptanib?

Answer 11

• pegylated RNA aptamer; bind to VEGF-A 165 isoform
• inhibits VEGF formation
• active intravitreally
• used for neovascular (wet) ARMD

Question 12

What are the characteristics of Brolucizumab?

Answer 12

• humanized, single-chain antibody that inhibits VEGF-A
• active intravitreally
• used for neovascular (wet) ARMD

Question 13

What are the characteristics of Verteporfin?

Answer 13

• Photosensitizing agent used in photodynamic therapy
• Intravenous admin., bound to LDL, absorbed by defective choroidal blood vessels
• then activated by non-thermal light source—>release free radicals that damage dysfunctional tissue
• halts progression of vision loss in pts with subfovea choroidal neovascularization
• used for treatment of choroidal neovascularization due to ARMD