Abstract
Purpose :
To describe the prevalence of diabetes mellitus (DM), diabetic retinopathy (DR), and the likelihood of diabetics receiving a diagnosis of DR based on ZIP Code in Chicagoland.
Methods :
Using the HealthLNK Data Repository, a collection of de-identified patient data from 5 Chicago-area academic medical centers and the Cook County health system, diabetic patients were defined with ICD-9 codes of 250.00-250.93, 357.2, 362.02-362.04. Patients with DR were defined by ICD-9 codes 362.01-362.07, and 364.42. Patients resided in 238 ZIP Codes. Differences in DM and DR between ZIP Codes were determined using relative risk (RR) and absolute relative risk (ARR) calculations in comparison to cited national prevalence rates. Only statistically significant differences between ZIP Codes were included on the data maps (p<0.0001).
Results :
Of the 1,061,067 patients analyzed in the HealthLNK database, 140,841 were identified with DM (prevalence of 13.2%), and 12,193 patients with DR (8.6% of diabetics). 36 ZIP Codes were identified with high RR of DM (2.69, Standard Error (SE) 0.03), high RR of DR (3.09, SE 0.12), but much lower than expected rate of DR diagnosis. Patients in these 36 ZIP Codes had a higher than average minority population (85.4%; Chicago average, 50.5%) and higher percent of households below the federal poverty line (33.0%; Chicago average, 17.9%). This data is represented in Figures 1 and 2.
Conclusions :
Certain ZIP Codes have a higher rate of DM. These ZIP Codes have a higher than average minority population and higher rate of households below the federal poverty line. These same ZIP Codes have lower than expected rates of DR. This finding of areas with a high rate of DM, high expected rate of DR, but low actual rate of DR can best be explained by lower frequency of eye exams to detect diabetic eye disease. Understanding the geographic distribution of this disparity can assist in determining optimal placement of screening resources.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.