Association between Decreased Renal Function and Reticular Macular Disease in Age-Related Macular Degeneration

To compare renal function in patients with age-related macular degeneration (AMD) with and without concurrent reticular macular disease (RMD).

Retrospective cohort study.

Patients with documented AMD with and without RMD.

Via our electronic health record system, we retrospectively identified patients assigned an International Classification of Diseases, Ninth Edition, code associated with AMD between January 2012 and January 2016. Patients met inclusion criteria if they had at least 1 macular spectral-domain optical coherence tomography volume scan, 1 provider note, and 1 glomerular filtration rate (GFR) value in the electronic medical record. We evaluated images for the presence or absence of RMD; we defined RMD as the presence of at least 1 subretinal drusenoid deposit in at least 1 macular slice. Patients with RMD in at least 1 eye were deemed RMD positive. Patients with bilateral choroidal neovascularization were excluded from analysis.

Observation of renal function in RMD patients.

Inclusion criteria were met by 119 patients (mean age, 75 years; range, 46-101 years). To account for the significant difference in RMD prevalence at extreme ages, we limited our study population to 107 patients 50 to 90 years of age. A GFR less than 60 ml/min/1.73 m² was found in 45.0% (27/60) of those with RMD compared with 12.8% (6/47) of those without RMD (odds ratio, 5.6; 95% confidence interval, 2.1-15). Multivariate logistic regression indicated that low GFR was a significant predictor for RMD, even after accounting for differences in age, diabetes, hypertension, hyperlipidemia, and other potential confounders. When comparing within classification subsets for RMD and GFR in patients with choroidal thickness data, significant choroidal thinning was associated with RMD (170 vs. 228 μm; P = 0.01) and GFR less than 60 ml/min/1.73 m² (144 vs. 219 μm; P = 0.0008).

Our analysis showed an association between RMD and renal dysfunction. Larger cross-sectional and longitudinal studies of the association of RMD with kidney function are warranted to better understand the nature and biological basis of this observed connection.