Systemic and Genetic Risk Factors for Reticular Macular Disease and Soft Drusen in Age- Related Macular Degeneration

Purpose: Soft drusen and subretinal drusenoid deposits (SDD) aka reticular macular disease (RMD) characterize two pathways to advanced age-related macular degeneration (AMD). We propose these pathways are distinct diseases, with distinct genetic risks, serum risks and associated systemic diseases. Methods: 126 Subjects with AMD had: retinal imaging for RMD status, serum risks, genetic testing, and histories of cardiovascular disease (CVD) and stroke. Results: 62 subjects had RMD, 64 were nonRMD (drusen only), 51 had CVD or Stroke. RMD correlated significantly with: ARMS2 risk allele (p= 0.019); lower mean serum HDL (61 vs. 69 mg/dl, p= 0.038, t test); CVD and troke (34/51 RMD, p= 0.001). NonRMD correlated/trended with: APOE2 (p= 0.032) and CETP (p= 0.072) risk alleles. 97 subjects total had some drusen, which correlated with CFH risk (p= 0.016). Multivariate independent risks for RMD were: CVD and Stroke (p= 0.008), and ARMS2 homozygous risk (p= 0.038). Conclusion: The RMD and soft drusen AMD pathways have distinct systemic associations, serum and genetic risks. RMD is associated with CVD and stroke, ARMS2 risk, and lower HDL; drusen with CFH risk and two lipid risk genes. These pathways appear to be distinct diseases leading to advanced AMD.