Objective: To estimate baseline cardiovascular risk of 1,123 participants in the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study and to assess cardiac event rates and the effect of screening on outcomes in these higher-risk participants.
Research design and methods: Baseline cardiovascular risk was assessed using four established methods: Framingham score, UK Prospective Diabetes Study (UKPDS) risk engine, criteria of the French-Speaking Association for the Study of Diabetes and Metabolic Diseases, and the presence or absence of metabolic syndrome. Cardiac events (cardiac death or nonfatal myocardial infarction) were assessed during the 4.8-year follow-up in participants with intermediate/high cardiovascular risk.
Results: By various risk-stratification approaches, 53-75% of participants were defined as having intermediate or high cardiovascular risk. The prevalence of inducible ischemia on screening in these individuals ranged from 21 to 24%, similar to lower-risk participants (19-23%). Cardiac event rates were greater in intermediate-/high-risk versus low-risk groups, but this was only significant for the UKPDS risk engine (4.2 vs. 1.2%, P = 0.002). The annual cardiac event rate was <1% in all risk groups, except in the high-risk UKPDS group (∼2% per year). In intermediate-/high-risk participants randomized to screening versus no screening, 4.8-year cardiac event rates were similar (2.5-4.8% vs. 3.1-3.7%).
Conclusions: A substantial portion of the DIAD population was defined as having intermediate/high baseline cardiovascular risk. Nevertheless, their annual cardiac event rate was low and not altered by routine screening for inducible ischemia.