Objectives: To determine if diabetic eye disease has changed over time among older Americans and to explore possibilities for observed change.
Methods: We performed a longitudinal analysis of nationally representative Medicare data, the Medicare 5% sample, collected from January 1, 1991, through December 31, 2004, using standard claims data algorithms and cross-sectional analysis of the Medicare Current Beneficiary Survey.
Results: Compared with Medicare beneficiaries first diagnosed with diabetes mellitus in 1994, those first diagnosed with diabetes in 1999 and in 2003 showed lower rates of background and proliferative diabetic retinopathy within 1 year after diagnosis and during 6 years of follow-up among the 1999 cohort. Six-year rates of surgical procedures for retinopathy were lower among beneficiaries in the 1999 cohort than in the 1994 cohort, and rates of glucose, lipid, and cholesterol monitoring were higher. In addition, hypertension was diagnosed more frequently among the 1999 cohort during 6 years. Data from the Medicare Current Beneficiary Survey showed higher rates of antihypertensive drug use among persons diagnosed with diabetes in 1999 compared with 1994.
Conclusions: Decreases in rates of diabetic retinopathy among persons newly diagnosed with diabetes enrolled in Medicare from 1994 to 2004 and concurrent improvements in primary care for diabetes suggest that better primary care has had an effect on the Medicare population, despite increasing rates of other adverse outcomes.