Because previous research suggests decreased kidney function could affect a patient’s chances of developing diabetic retinopathy (DR), researchers from the University of Pennsylvania took a closer look at national medical claims databases to further study the possible association.

The results of their retrospective observational study, presented at last week’s ARVO meeting in Vancouver, included claims from 69,982 patients with nonproliferative DR (NPDR)—18.2% of whom developed vision-threatening DR within a median of 1.5 years. The researchers examined both diagnostic codes and lab results of serum creatinine, which identified kidney disease with and without end-stage renal disease based on the estimated glomerular rates.

The researchers found lower estimated glomerular rates, signifying worse renal function, was associated with a higher risk of vision-threatening DR compared with patients with higher glomerular rates. Although those who were diagnosed with end-stage renal disease had an increased risk of developing vision-threatening DR, patients with kidney disease without end-stage renal disease did not, at least compared with normal patients.

The researchers concluded that kidney disease—identified using either diagnostic codes or lab values—is associated with increased risk of vision-threatening DR. Neither diagnostic approach changed the researchers’ ability to predict the development of DR.