Monday, February 25, 2008

Nutrition in AMD

Pharmacologic treatments for wet AMD

  • verteporfin(Visudyne)
  • pegaptanib (Macugen)
  • Lucentis
  • Avastin
Natural history of AMD progression

  • 10% rate of conversion from dry to wet AMD
  • nutritional supplementation decreases risk
  • oxidation hypothesis: breakdown of antioxidant systems and generation of free radicals damages lipid membranes; antioxidant deficiency may predispose patient to disease

AMD and cardiovascular disease

  • shared risk factors: elevated lipids, cholesterol, CRP, arteriosclerosis, cigarette smoking, inflammatin, HTN

  • category 1 or 2 (little-to-no AMD or few small drusen): risk of developing wet AMD at 5 years = 1.5%
  • category 3 (large intermediate-size drusen or nonvoeal geographic atrophy): risk of developing wet AMD at 5 years = 20%
  • category 4 (at least 1 eye with wet AMD or foveal geographic atrophy)
  • if wet AMD present in one eye, risk to the fellow eye is 45%
  • risk for vision loss at 5 years: antioxidant + zinc = 20% reduction in risk
  • risk for progression to wet AMD at 5 years: antioxidant + zinc or zinc alone = 25% reduction in risk
  • recommendations: patients with intermediate to advanced AMD (category 3 or 4) should take daily supplemental theraphy
  • people who smoke should avoid beta carotene due to increased risk of lung cancer

  • study of lutein, zeaxanthin, omega-3 fatty acids
  • lutein and zeaxanthin are natural carotenoids found in macula; antioxidants; filters of UV light; play role in structural signal transduction; macular pigment decreases with age; decrease predisposes patient to increased rsik for AMD
  • zeaxanthin can increase macular pigment
  • 6m lutein associated with reduced risk for develping AMD by up to 43%
Dietary fat

  • higher body mass index associated with greater AMD risk
  • high intake of fat in prcessed baked gods increases odds for developing wet AMD by 2.4
  • other sources of fat (nuts) protective
Omega-3 fatty acids

  • lutein, zeaxanthin, and omega-3 fatty acids not produced by body
  • high intake of omega-3 fatty acids protects against wet AMD (dose-dependent)
  • omega-3 fatty acids in broiled or baked fish: dose-dependent decrease in risk for AMD progression


  • high levels of beta-carotene linked to increased incidence of lung cancer among heavy smokers
  • high volumes of zinc linked with genitourinary and GI disorders

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