Purchase this article with an account.
Zohar Yehoshua, Carlos Alexandre de Amorim Garcia Filho, Renata Portella Nunes, Giovanni Gregori, Fernando M Penha, Andrew A Moshfeghi, Kang Zhang, Srinivas R Sadda, William J Feuer, Philip J Rosenfeld; Association between growth of geographic atrophy (GA) and the complement factor I (CFI) Locus. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):2845.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate whether the at-risk SNP in the CFI locus, which was found to be associated with rapid progression of geographic atrophy in the MAHALO trial, was also associated with an increased growth of GA in COMPLETE trial participants.
Blood samples collected from the 30 COMPLETE trial GA patients were genotyped using the following SNPs: complement factor I (CFI) (rs17440077), complement factor H (CFH)(rs1329428), and C3 (rs 2230199) C2/CFB (rs429608) (Yaspan, B. ARVO 2014, Abstract 2234, A common SNP at the CFI locus is associated with rapid progression og GA).GA growth was measured using autofluorescence imaging with a fundus camera-based flash system and confocal scanning laser ophthalmoscopy system, as well as spectral-domain (SD) optical coherence tomography (OCT). OCT fundus images were derived from a slab beneath the retinal pigment epithelium (sub-RPE slab). Growth of GA in the 24 study eyes of COMPLETE patients meeting MAHALO eligibility criteria was compared between those carrying and not carrying the CFI at risk allele using the 2 sample t-test.
The prevalence of at-risk alleles among the 30 patients in the complete study was: CFI, 19 (63%); CFH, 28 (93%); C3, 11 (36%); C2/B, 30 (100%). Growth of GA in eyes of patients without the CFI at risk allele was slightly, but not significantly faster than growth in eyes of those carrying the CFI at risk allele (P≥0.55). Growth rate based on the sub-RPE slab at 52 week was 2.05±1.13mm2 (0.40±0.21 mm using the difference in the square root of the areas) for patients without any CFI at-risk alleles and 1.83±1.41mm2 (0.36±0.23 mm using the difference in the square root of the areas) for patients with at least one CFI at-risk allele (P≥0.7).
The COMPLETE study is small but similar in size to the MAHALO trial. In contrast to the MAHALO trial, COMPLETE patients, who were carriers of the at-risk allele for CFI, were not found to have faster progression of GA compared with those without the at-risk allele. Additional and larger studies are needed to confirm or refute the association of CFI with GA progression.
This PDF is available to Subscribers Only