Laboratory-based calculation of coronary heart disease risk in a hospital diabetic clinic

Aims To develop an estimation of risk of coronary heart disease (CHD) based on the Framingham equation for use in a diabetes clinic, given concerns ab out the accuracy of the Sheffield risk tables in this setting. Methods A computer program using the Framingham equation based on patients' age, sex, systolic blood pressure, smoking history, presence of diabetes a nd left ventricular hypertrophy was applied to requests for lipid screening of patients attending the diabetes clinics of Birmingham Heartlands Hospit al. The calculated risks for the population were compared with those estima ted from the Sheffield tables. Results Of 1060 patients with diabetes mellitus, 215 (20%) had an annual CH D risk greater than or equal to 3%, which is considered to he the threshold at which lipid-lowering drugs are cost-effective. Only 24 of these 215 pat ients (11%) were correctly identified by the Sheffield tables, which we con clude have an unacceptably low sensitivity in diabetes mellitus. Conclusions A laboratory-based CHD risk calculation system is a practical a lternative to the Sheffield system and may have a greater sensitivity in th e diabetic clinic.