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OBJECTIVE -The aim of this study was to determine the predictive value of silent myocardial ischemia (SMI) and cardiac autonomic neuropathy (CAN) in asymptomatic diabetic patients.RESEARCH DESIGN AND METHODS -We recruited 120 diabetic patients with no history of myocardial infarction or angina, a normal 12-lead electrocardiogram (ECG), and two or more additional risk factors. SMI assessment was carried out by means of an ECG stress test, a thallium-201 myocardial scintigraphy with dipyridamole, and 48-h ECG monitoring. CAN was searched for by standardized tests evaluating heart rate variations. Accurate follow-up information for 3-7 years (mean 4.5) was obtained in 107 patients.RESULTS -There was evidence of SMI in 33 patients (30.7%). CAN was detected in 33 of the 75 patients (38.9%) who were tested, and a major cardiac event occurred in 11 of them. Among these 75 patients, the proportion of major cardiac events in the SMI ϩ patients was not significantly higher than that in the SMI Ϫ patients (6 of 25 vs. 5 of 50 patients), whereas it was significantly higher in the CAN ϩ patients than in the CAN Ϫ patients (8 of 33 vs. 3 of 42 patients; P = 0.04), with a relative risk of 4.16 (95% CI 1.01-17.19) and was the highest in the patients with both SMI and CAN (5 of 10 patients). After adjusting for SMI, there was a significant association between CAN and major cardiac events (P = 0.04).CONCLUSIONS -In asymptomatic diabetic patients, CAN appears to be a better predictor of major cardiac events than SMI. The risk linked to CAN appears to be independent of SMI and is the highest when CAN is associated with SMI.

In poorly controlled NIDDM patients, sE-selectin levels are increased and significantly fall to normal after short-term improvement of glycemic control. This suggests that assaying sE-selectin makes it possible to detect endothelium activation and to follow its reversal with euglycemia.

This study shows that (1) responses of angiographically normal CAs to CPT and to flow increase are impaired in diabetic patients; (2) abnormal responses are not improved by L-arginine, suggesting that a deficit in substrate for nitric oxide synthesis is not involved; and (3) deferoxamine restores a vasodilator response to the two tests, suggesting that inactivation of NO by oxygen species might be partly responsible for the impairment of CA dilation in diabetic patients.

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These data are strongly in favour of the role of cardiac autonomic neuropathy in hypertension in diabetic patients. The association of the cardiac autonomic neuropathy/hypertension profile with vascular complications is consistent with a deleterious effect on vascular hemodynamics and structure, additional to the effects of hypertension.

OBJECTIVE -Silent myocardial ischemia (SMI) in asymptomatic subjects with no history of myocardial infarction or angina is a frequent condition in diabetic patients. The aim of the study was to examine the predictive value of SMI for cardiac events in a multicenter cohort and to determine whether this value is higher in patients with a particular clinical profile. RESEARCH DESIGN AND METHODS-A total of 370 asymptomatic diabetic patients with at least two additional cardiovascular risk factors was recruited in four departments of diabetology. SMI was assessed by either exercise or dipyridamole single-photon emissioncomputed tomography myocardial perfusion imaging with thallium-201. If dipyridamole stress was used, an electrocardiogram stress test was performed separately on another day. Follow-up duration was 3-89 months (38 Ϯ 23 months).RESULTS -There was evidence of SMI in 131 patients (35.4%) on at least one positive noninvasive test. The patients with SMI were significantly older and had significantly higher serum triglycerides and lower HDL cholesterol levels. Cardiac events occurred in 53 patients (14.3%). Major cardiac events (death or myocardial infarction) occurred in 38 patients (10%) and other events (unstable angina, heart failure, or coronary revascularization) occurred in 15 patients. The patients who had cardiac events were older and had higher serum triglyceride levels at baseline. There was a significant association between SMI and cardiac events (hazard ratio 2.79 [95% CI 1.54 -5.04]) and in particular major cardiac events (3 [1. 53-5.87]). In the patients Ͼ60 years of age, the prevalence of SMI was higher (43.4 vs. 30.2% in those Ͻ60 years). SMI was associated with a significant risk of cardiac events (2.89 [1.31-6.39]) and in particular major cardiac events (3.66 [1.36 -9.87]) for the patients Ͼ60 years old but not for those Ͻ60 years old. CONCLUSIONS -In asymptomatic diabetic patients with additional cardiovascular risk factors, SMI is a potent predictor of cardiac events and should be assessed preferably in the patients Ͼ60 years of age. Diabetes Care 28:2722-2727, 2005T he prognostic value of type 1 silent myocardial ischemia (SMI) according to the Cohn classification, i.e., myocardial ischemia in asymptomatic subjects with no history of myocardial infarction or angina (1), has been evaluated in several studies in the general population. One of them had included 2,014 asymptomatic men whose mean age was 50 years and showed that within 13 years of follow-up, the rate of major cardiac events was four to five times higher in the patients with a positive exercise electrocardiogram (ECG) test than in those with a normal ECG stress test (2). Other studies have shown that a positive exercise ECG test predicts a 3-14 times higher rate of major cardiac events (3,4). Silent ischemic episodes during 24-h ECG monitoring have also been shown to be associated with a higher rate of major cardiac events in patients who suffer from unstable angina, myocardial infarction, or ECG ischemic changes at low level...

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