Risk of coronary artery disease in type 2 diabetes and the delivery of care consistent with the chronic care model in primary care settings: a STARNet study

Abstract

Background: Modifiable risks for coronary heart disease (CHD) in type 2 diabetes include glucose, blood pressure, lipid control, and smoking. The chronic care model (CCM) provides an organizational framework for improving these outcomes.

Objective: To examine the relationship between CHD risk attributable to modifiable risk factors among patients with type 2 diabetes and whether care delivered in primary care settings is consistent with the CCM.

Subjects/methods: Approximately 30 patients in each of 20 primary care clinics. CHD risk factors were assessed by patient survey and chart abstraction. Absolute 10-year CHD risk was calculated using the UK Prospective Diabetes Study risk engine. Attributable risk was calculated by setting all 4 modifiable risk factors to guideline indicated values, recalculating the risk, and subtracting it from the absolute risk. In each clinic, the consistency of care with the CCM was evaluated using the Assessment of Chronic Illness Care (ACIC) survey.

Results: Only 15.4% had guideline-recommended control of A1c, blood pressure, and lipids. The absolute 10-year risk CHD was 16.2% (SD 16.6). One-third of this risk, 5.0% (SD 7.4), was attributable to poor risk factor control. After controlling for patient and clinic characteristics, the ACIC score was inversely associated with attributable risk: a 1 point increase in the ACIC score was associated with a 16% (95% CI, 5-26%) relative decrease in attributable risk.

Discussion: The degree to which care delivered in a primary care clinic conforms to the CCM is an important predictor of the 10-year risk of CHD among patients with type 2 diabetes.