Improvements in diabetes processes of care and intermediate outcomes: United States, 1988-2002

Abstract

Background: Progress of diabetes care is a subject of public health concern.

Objective: To assess changes in quality of diabetes care in the United States by using standardized measures.

Design: National population-based, serial cross-sectional surveys.

Setting: National Health and Nutrition Examination Survey (1988-1994 and 1999-2002) and the Behavioral Risk Factor Surveillance System (1995 and 2002).

Participants: Survey participants 18 to 75 years of age who reported a diagnosis of diabetes.

Measurements: Glycemic control, blood pressure, low-density lipoprotein (LDL) cholesterol level, annual cholesterol level monitoring, and annual foot and dilated eye examination, as defined by the National Diabetes Quality Improvement Alliance measures.

Results: In the past decade, the proportion of persons with diabetes with poor glycemic control (hemoglobin A1c > 9%) showed a nonstatistically significant decrease of 3.9% (95% CI, -10.4% to 2.5%), while the proportion of persons with fair or good lipid control (LDL cholesterol level < 3.4 mmol/L [<130 mg/dL]) had a statistically significant increase of 21.9% (CI, 12.4% to 31.3%). Mean LDL cholesterol level decreased by 0.5 mmol/L (18.8 mg/dL). Although mean hemoglobin A1c did not change, the proportion of persons with hemoglobin A(1c) of 6% to 8% increased from 34.2% to 47.0%. The blood pressure distribution did not change. Annual lipid testing, dilated eye examination, and foot examination increased by 8.3% (CI, 4.0% to 12.7%), 4.5% (CI, 0.5% to 8.5%), and 3.8% (CI, -0.1% to 7.7%), respectively. The proportion of persons reporting annual influenza vaccination and aspirin use improved by 6.8 percentage points (CI, 2.9 percentage points to 10.7 percentage points) and 13.1 percentage points (CI, 5.4 percentage points to 20.7 percentage points), respectively.

Limitations: Data are self-reported, and the surveys do not have all National Diabetes Quality Improvement Alliance indicators.

Conclusion: Diabetes processes of care and intermediate outcomes have improved nationally in the past decade. But 2 in 5 persons with diabetes still have poor LDL cholesterol control, 1 in 3 persons still has poor blood pressure control, and 1 in 5 persons still has poor glycemic control.