6.1.1: Understands risk factors for common ocular conditions

Question 1

What are the risk factors of POAG?

Answer 1

• FH - 1st degree relative - genetic component associated. Most concerned if sibling as more similar age
• Age - prevalence increases w/ age - vulnerability of optic nerve, less able to withstand higher IOP
• High IOP - main treatable RF
• Afro-caribbean ethnicity - 2-3x more likely than caucasian - research indicates specificc genetic mutations
• Thin CCT - study shows can be RF
• DM type 2 - can cause abnormal BVs to grow out of retina and block fluid draining out of eye
• Myopia - eyes are larger so makes thinner & optic nerve more vulnerable to changes in IOP

Question 2

What are the risk factors for NTG?

Answer 2

• Migraines - curren ttheory is that blood flow is compromise in people w/ migraines
• Raynauds - lower BP or decreases ocular blood flow may render optic nerve more susceptivle to development of glaucoma
• Japanese ethnicity

Question 3

What are the risk factors for CAG?

Answer 3

• Age - size of lens increases with age, narrower angle
• Female: 2-3x narrower angles than men
• Hyperopia - increased risk as smaller eyes
• East Asian ethnicity: smaller eyes, narrower angles

Question 4

What are the risk factors for cataract?q

Answer 4

• Age- gradual accumulation of yellow/brown pigment. Pigment denaturation - proteins in lens fibres denature and become opaque (cataract)
• UV exposure - speeds up protein denature process
• Smoking - increases oxidative stress & damages proteins
• Steroid use - risk of PSCC - steroid induced changes in gene transcription within lens epithelial cells.
• Trauma - penetrating or blunt, breach anterior lens capsule

Question 5

What are the risk factors for diabetic retinopathy?

Answer 5

• duration of DM - BVs weak for longer time so more likely to leak
• poor control - increases blood flow due to higher glucose levels, damages endothelial lining of BVs and leaking

Question 6

What are the risk factors for AMD?

Answer 6

• Age - causes damage to macula, wear & tear
• Smoking - reduces effectiveness of antioxidants & may deplete levels of lutein in macula. Smoke also decreases O2 to choroid (BVs which supply retina)
• HBP - decreases choroidal blood flow - causes geographic atrophy & stimulates choroidal neovascularistion (wet AMD)
• AMD in other eye
• Diet: low in omega 3 and 6, vitamin A, C & E, carotenoid (lutein) & minerals (zinc). High in saturated fat & cholesterol. High glycaemic index. Antioxidant stress, anti-inflammatory inhibition of RPE cell damage & inhibition of neovascularisation
• UV exposure - induce oxidative stress to RPE
• Family history
• Female > Male