Purpose:
To relate the age at onset of neovascular age-related macular degeneration (nvAMD) to genotype for the two well characterised risk loci (CFH and ARMS2), smoking status and other clinical covariates.
Methods:
249 participants with an angiographically confirmed diagnosis of nvAMD were recruited from a specialist macular clinic. Participants were genotyped for both ARMS2 and CFH risk alleles. Covariates available for analysis included age, gender, smoking, body mass index and cardiovascular status. The age at onset was defined as the first record of central visual loss in either eye of a participant and was determined from a retrospective examination of clinic notes. This could not be reliably determined in 55 patients leaving 194 available for analysis.
Results:
Linear regression showed that age at onset was approximately 3 years earlier in those classified as obese compared to normal BMI, 4 years earlier in current smokers when compared to never and 5 years earlier in those with two copies of the ARMS2 risk allele compared to none. Number of CFH risk alleles was not associated with age at onset.
Conclusions:
Reducing body mass index and stopping smoking may delay the onset of nvAMD even in the presence of the effect of high risk genotypes.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: risk factor assessment • gene modifiers