Objectives: To compare the prevalence of type 2 diabetes mellitus in the U.S. elderly population between 1988 to 1994 and 1999 to 2004 and to assess glycemic control and comorbid conditions in this population.
Design: Serial U.S. population-based cross-sectional surveys.
Setting: National Health and Nutrition Examination Surveys (1988-1994 and 1999-2004).
Participants: Survey participants aged 65 and older with type 2 diabetes mellitus.
Measurements: Glycemic control, measured as hemoglobin A1C (hA1C) less than 7%, prevalence of comorbid conditions, pharmacologic treatment rate, blood pressure, and serum cholesterol.
Results: The prevalence of diagnosed type 2 diabetes mellitus in the U.S. elderly population increased from 12.0% to 14.1% (P=.004) between 1988 and 2004. Many patients had comorbid conditions; in 1999 to 2004, 36.7% had nephropathy, 31.5% renal insufficiency, 20.2% history of myocardial infarction, and 17.9% heart failure. The proportion of patients treated with antihyperglycemic medication increased from 75.1% in 1988 to 1994 to 85.6% in 1999 to 2004 (P<.001), and glycemic control rates also improved, from 44.7% to 54.8% (P<.001). Greater improvement in glycemic control rates was evident in patients without comorbidities (P<.001). Adjusted for patient characteristics, including duration of diabetes mellitus, patients with nephropathy or renal insufficiency were 40% less likely to achieve controlled hA1C as those without.
Conclusion: Despite improvements in the rates of treatment and glycemic control, approximately half of elderly patients diagnosed with type 2 diabetes mellitus have hA1C levels of 7% or higher. Many patients suffer from comorbid conditions, which may present a challenge for successful diabetes mellitus management.