Back grey_arrow_rt.gif
Cardiovascular risk calculators of questionable value in type 2 diabetes
NEW YORK (Reuters Health) - Three cardiovascular disease (CVD) risk equations -- Framingham, SCORE, and DECODE -- do not provide reliable CVD-related mortality estimates in patients with type 2 diabetes, clinicians from the UK caution in a report in the May issue of Diabetes Care.
According to the authors, the Framingham risk equations for coronary heart disease and CVD, which are based on age, sex, blood pressure, cholesterol (total and HDL), and smoking, with diabetes status as a categorical variable, have been validated in general populations but not in diabetic patients.
The Systematic Coronary Risk Evaluation (SCORE) Project risk scores for fatal heart disease and CVD "appear to overestimate risk in the general population and have not been evaluated in diabetes," they further note.
The Diabetes Epidemiology: Collaborative Analysis of Diagnostic Criteria in Europe (DECODE) Study Group developed their fatal CVD risk equation following recognition of glycemia as a CVD risk factor.
Dr. Rury R. Holman of the Oxford Center for Diabetes, Endocrinology, and Metabolism and colleagues used data from the UK Prospective Diabetes Study to evaluate these three risk equations in 5,102 patients with newly diagnosed type 2 diabetes.
The 10-year fatal CVD event rate in the UK cohort was 7.4%. According to the team, the Framingham risk equation underestimated this rate by 32%, with an absolute risk of 5.0%.
The SCORE equation overestimated 10-year fatal CVD risk by 18% with an absolute risk of 8.7%, whereas the DECODE risk calculator yielded an "acceptable estimate" with an absolute risk of 6.6%.
Sex differences were also observed. For men, only the SCORE equation provided a reasonable estimate. For women, only the Framingham risk equation performed well.
The 5-year fatal CVD event rate in the UK cohort for patients who had diabetes for a median of 5 years was 4.5%. The Framingham equation underestimated this rate by 56% with an absolute rate of 2.0%, whereas both the SCORE and DECODE equations yielded overestimates (absolute rates: 5.6% and 15.6%, respectively).
The SCORE and DECODE calculators appropriately estimated fatal CVD in men but not women.
"This report," Dr. Holman and colleagues conclude, "emphasizes the need for validated diabetes-specific risk calculators that can estimate CVD risk reliably in type 2 diabetic patients."
Diabetes Care 2007;30:1292-1294.
  icon paper stack View Older Articles   Back to Top