The association of geographic atrophy and decreased renal function in patients with age-related macular degeneration.

PurposeThe purpose of the study was to investigate the association between area and presence of geographic atrophy (GA) and renal function, as measured by glomerular filtration rate (GFR).Patients and methodsWe retrospectively identified patients aged 50-90 years who were assigned an ICD-9 diagnosis code for age-related macular generation (AMD) between January 2012 and January 2016. Patients met inclusion criteria if they had at least one macular spectral domain optical coherence tomography volume scan, one provider note, and one GFR value in the electronic medical record. Images were evaluated for the presence of GA, area of GA, drusen, and subretinal drusenoid deposits (SDD) and for subfoveal choroidal thickness (CTh) by standard criteria. Imaging findings were correlated with the most recent GFR from the patient's chart.ResultsWe identified 107 patients who met our inclusion criteria (mean age=74 years, range 50-90 years). Overall, we found a significant correlation between the presence of GA and reduced GFR (P=0.002), which was maintained even after accounting for age and other confounders. No association between GFR and GA area was found. CTh was significantly lower in patients with GA (P=0.038) and those with decreased GFR (P=0.004). Within the SDD-positive population, GA was associated with reduced GFR (P=0.007) but only trended toward significance after controlling for age.ConclusionOur study findings demonstrate an association between impaired renal function and the presence, but not area, of GA within an AMD population. These findings may shed light on common pathogenic mechanisms for these two diseases.