“Dry” Age Related Macular Degeneration Pearls

By Rahul Khurana, MD

Early Age-Related Macular Degeneration (AMD) (referred to as DRY) is a charged diagnosis that can bring much fear and anxiety to patients. Most patients know someone who became blind due to advanced AMD (referred to as WET), and are worried that the same will happen to them. Fortunately, with the revolutionary Anti-VEGF therapies, this is often not the case and they can be reassured. Furthermore, here are a few “pearls” in managing your early AMD patients.

• Stop Smoking: After aging, smoking is the most significant risk factor for developing Advanced AMD. All patients with early AMD should be counseled on smoking cessation.
  


• Anti-Oxidant Vitamins: The Age-Related Eye Disease Study (AREDS) was a randomized, placebo-controlled trial that showed that a combination of anti-oxidants and zincs (Oral Preservision) reduced the progression to advanced AMD by 25% in patients with intermediate AMD (defined as extensive (>6) intermediate drusen ( >64 µm in size) or with large drusen (>125 µm; width of a large vein at disc margin). Patients with early AMD had no benefit.
  
  Some would argue that all patients with AMD should take it regardless, as there is little downside to the vitamins. However, many of these patients already take many medications and adding another with little to no benefit might be problematic with polypharmacy. In addition, it can be expensive. One of the high-dose antioxidants studied was beta-carotene which was found to increase the risk of lung cancer among smokers. Thus, smokers with intermediate AMD should take the AREDS vitamins without beta-carotene.
  


• Home Amsler Grid Testing: It is essential that patients with early AMD test each of their eyes regularly. Advanced AMD can progress slowly and it can often be missed by patients. Therefore, it is imperative that early AMD patients have regular visits with their ophthalmologists and check each eye individually at home. It has been shown that diagnosing advanced AMD early often leads to better results with Anti-VEGF therapy.
  


• Estimating RISK: Many AMD patients want to know their likelihood of developing Advanced AMD. A simplified severity scale was developed from the AREDS to estimate likelihood of progression after five years. The scoring system assigns to each eye one point for the presence of large drusen, one point for the presence of any pigment abnormality, and two points for advanced AMD. Risk factors are summed across both eyes, yielding a five point scale (0-4) on which the approximate five-year risk of developing advanced AMD in at least one eye increases:
  


• 0 Points, 0.5%
• 1 Point, 3%
• 2 Points, 12%
• 3 Points, 25%
• 4 Factors, 50%

I find this scale simple to calculate from a clinical exam and a quick way to convey risk of progression to patients.

These are some simple “pearls” that are helpful in managing early AMD patients. There are many new treatments on the horizon that should give us more options in the future.