Cardiovascular Risk Prediction Is Improved by Adding Asymptomatic Coronary Status to Routine Risk Assessment in Type 2 Diabetic Patients

Abstract

OBJECTIVETo evaluate if silent myocardial ischemia (SMI) and silent coronary artery disease (CAD) provide significant additional value to routine cardiovascular risk assessment in type 2 diabetic patients.RESEARCH DESIGN AND METHODSWe followed up to a first cardiovascular event 688 subjects (322 men, aged 59 ± 8 years) out of 731 consecutive asymptomatic type 2 diabetic patients with ≥1 additional risk factor who had been prospectively screened between 1992 and 2006 for SMI by stress myocardial scintigraphy and for silent CAD by coronary angiography.RESULTSSMI was found in 207 (30.1%) patients and CAD in 76 of those with SMI. Of the patients, 98 had a first cardiovascular event during a 5.4 ± 3.5 (range: 0.1–19.2) year follow-up period. Cox regression analysis considering parameters predicting events but not SMI and CAD (“routine assessment”) showed in univariate analyses that macroproteinuria (hazard ratio [HR] 3.33 [95% CI 1.74–6.35]; P < 0.001), current multifactorial care (0.27 [0.15–0.47]; P < 0.001), and peripheral/carotid occlusive arterial disease (PCOAD; 4.33 [2.15–8.71]; P < 0.001) independently predicted cardiovascular events. When added into the model, SMI (HR 1.76 [1.00–3.12]; P = 0.05) and CAD (2.28 [1.24–4.57]; P < 0.01) were also independently associated with events. SMI added to the prediction of an event in the following 5 years above and beyond routine assessment risk prediction (c statistic with or without SMI 0.788 [0.720–0.855] and 0.705 [0.616–0.794], respectively).CONCLUSIONSAlthough screening for SMI and silent CAD should not be systematic, these complications are predictive of cardiovascular events in type 2 diabetic patients in addition to routine risk predictors, especially represented by PCOAD, macroproteinuria, and nonintensive management.