Factors associated with increased mortality in AMD
Survival in age-related macular degeneration (AMD) may be reduced in patients with late disease, bilateral cataract surgery and poor visual acuity, according to data from the Age-Related Eye Disease Study 2 (AREDS2). Moreover, oral supplementation with omega-3 fatty acids, lutein plus zeaxanthin, zinc or beta-carotene does not significantly affect mortality.
AREDS2 randomized 4,203 patients with at least intermediate AMD to receive lutein/zeaxanthin and/or omega-3 fatty acids for treatment of AMD and cataract. Baseline and annual assessments included best-corrected visual acuity (BCVA), slit-lamp examinations and stereoscopic fundus photographs that were centrally graded for development of late AMD (central geographic atrophy or neovascular AMD) or pseudophakia.
Of the patients, 368 died during a median follow-up of 5 years. In Cox proportional hazards models, mortality was elevated in patients with neovascular AMD in one eye at baseline than in those with no or few drusen (hazard ratio [HR], 1.56; 95 percent CI, 1.21 to 2.01; p<0.001).
Survival was also poor for patients with bilateral cataract surgery before enrolment than for those with baseline bilateral phakia (HR, 1.63; 1.29 to 2.07; p<0.001), as well as for patients with BCVA of <20/40 vs those with ≥20/40 (HR, 1.56; 1.06 to 2.30; p=0.024).
On the other hand, mortality was lower in patients who received antivascular endothelial growth factor therapies for neovascular AMD than in those who did not (HR, 0.71; 0.57 to 0.88; p=0.002).
The association between all-cause mortality and AREDS2 treatment did not significantly differ whether assessing the main or individual treatment effect (omega-3 fatty acids main effect: HR, 1.18; 0.96 to 1.45; p=0.12; lutein/zeaxanthin main effect: HR, 1.04; 0.85 to 1.28; p=0.71).