Sociodemographic variables associated with risk for diabetic retinopathy.

Background: Several systemic and sociodemographic factors have been associated with the development and progression of diabetic retinopathy (DR). However, there is limited investigation of the potential role sociodemographic factors may play in augmenting systemic risk factors of DR. We hypothesize that age, sex, race, ethnicity, income, and insurance payor have an impact on hemoglobin A1c (HbA1c), body mass index, and systolic blood pressure, and therefore an upstream effect on the development of DR and vision-threatening forms of DR (VTDR).

Methods: Multivariable analysis of longitudinal electronic health record data at a large academic retina clinic was performed. Sociodemographic factors included race, ethnicity, income, and insurance payor. Systemic risk factors for DR included hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and body mass index (BMI). VTDR was identified from encounter diagnostic codes indicating proliferative retinopathy or diabetic macular edema. Patient-reported primary address zip codes were used to approximate income level, stratified into quartiles.

Results: From 2016 to 2018, 3,470 patients with diabetes totaled 11,437 visits were identified. Black patients had higher HbA1c and SBP compared to White patients. White patients had higher BMI and SBP compared to patients of unknown/other race and greater odds of VTDR than the latter. Patients of Hispanic ethnicity had significantly higher SBP than non-Hispanic patients. Low-income patients had higher BMI and SBP than high-income patients and greater odds of VTDR than the latter. Medicaid recipients had greater odds of VTDR than those with Blue Care Network (BCN) and Blue Cross Blue Shield (BCBS) insurance. Medicaid and Medicare recipients had higher SBP compared to BCBS recipients. Finally, both higher HbA1c and SBP had greater odds of VTDR. There were no differences in odds of VTDR between White and Black patients or between Hispanic and non-Hispanic patients.

Conclusion: Significant associations exist between certain sociodemographic factors and well-known risk factors for DR. Income and payor were associated with increased severity of systemic risk factors and presence of VTDR. These results warrant further investigation of how risk factor optimization and disease prevention may be further improved by targeted intervention of these modifiable sociodemographic factors.