Abstract
Purpose :
To assess if there is a statistically significant difference in Hemoglobin A1c (HbA1c) levels across four different variables: age, race, insurance status and best-documented visual acuity (BDVA).
Methods :
A retrospective chart review was performed from Jan 2013 to Dec 2015, using the Northwestern Enterprise Data Warehouse to identify all diabetic patients with 2 ophthalmologic evaluations within a 3-year span. Inclusion criteria were a diagnosis of diabetes with ICD-9 codes of 250.00-250.93, an age of 18 and over, and at least one HbA1c result over the last year. The following data points were examined: HgbA1c, age, race (Caucasian, African American, Hispanic/Asian/Other), insurance status (Medicaid, Medicare, private, uninsured), and BDVA. Visual acuities were grouped in clusters: 20/40 or better, 20/50 – 20/80, 20/100 or worse. Statistical significance was defined as p-value <0.05.
Results :
A total of 3209 patients were included in the study. The mean age of patients was 61.4 years. The mean HgbA1c was 7.15 mg/dl. Over 95% of patients had a visual acuity of 20/40 or better. Medicare comprised 42% of patients, private insurance 40%, uninsured 12%, and Medicaid 6%. HbA1c was found to decrease 0.17 mg/dl with every year of age. The mean HbA1c for Caucasians compared with African Americans was lower by 0.38 mg/dl, while Caucasians compared with Hispanics/Asian/Others was lower by 0.32 mg/dl. Uninsured patients had a higher mean HbA1c compared with private insurance patients by 0.24 mg/dl, and Medicare patients by 0.65 mg/dl. Medicare patients had a lower HbA1c compared with Medicaid patients by 0.58 mg/dl, and private patients by 0.41 mg/dl. All reported differences in means were found to be statistically significant. There was no statistically significant correlation between HbA1c and BDVA.
Conclusions :
HbA1c was found to decrease with every year of age. This may help explain the result of the Medicare population having the lowest overall HbA1c of any insurance group, as the Medicare population begins at 65 years, and our mean age of all patients was 61 years. Caucasians were found to have the lowest overall HbA1c. There was no correlation with HbA1c and visual acuity; however, over 95% of patients had a visual acuity of 20/40 or better.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.