Abstract 17870: Is Diabetes Really a Coronary Artery Disease risk Equivalent?
Background: Diabetes mellitus (DM) is considered as a coronary artery disease (CAD) risk equivalent by current guidelines based on cohort studies from the ‘70s and ‘80s, though more recent studies dispute it. The purpose of our study was to determine if DM was a CAD risk equivalent for all-cause mortality in an exercise testing population.
Methods: We performed a retrospective cohort study of 45,756 patients ≥ 18 years referred for a treadmill exercise testing (TMET) to a preventive cardiology clinic from August 1993 to May 2006. We divided patients according to their history of DM and CAD and selecting two study groups: DM-NonCAD and CAD-NonDM. Multivariate Cox proportional hazard models examined the mortality risk and obtained the hazard ratio (HR) for DM-NonCAD vs CAD-NonDM. Covariates included age, gender, functional aerobic capacity, other TMET parameters such as abnormal electrocardiogram with exercise and heart rate recovery, medications (aspirin, beta-blockers, lipid lowering agents), smoking status, body mass index, hypertension and dyslipidemia.
Results: A total of 7929 patients were included for the analysis; divided in DM-NonCAD (n=2282) and CAD-NonDM (n=5647). Mean age (years) was 57±11 and 63±11, for DM-NonCAD and CAD-NonDM, respectively. There were 1500 deaths after 12.3 years of follow up, 206 (9%) in the DM-NonCAD group and 1294 (23%) in the CAD-NonDM group. For the fully adjusted model the DM-NonCAD group, compared with CAD-NonDM group, had a HR of 0.56 (95% confidence interval 0.46-0.66; p < .0001) for all-cause mortality (Table).
Conclusion: DM is not a CAD risk equivalent for all-cause mortality when tested in an exercise testing contemporary cohort. Guidelines for primary prevention of CAD and lipid management overestimate the risk in patients with DM.
- © 2013 by American Heart Association, Inc.