Consequences of Diabetes

This is the third of three articles dealing with the International Diabetes Federation meeting, which was held in Paris, 24–29 August 2003. Paul Valensi (Bobigny, France) discussed approaches to silent myocardial ischemia in persons with diabetes. Addressing the question of whether it is in fact advisable to detect cardiovascular disease (CVD) in persons without history of myocardial infarction or angina, he noted the poor prognosis of persons with diabetes, whose risk of myocardial infarction in the absence of CVD is similar to that of persons without diabetes and with a prior myocardial infarction. Those having evidence of CVD are at particularly increased risk, with half dying within 8 years (1). One-year mortality after thrombolysis is increased by half in persons with diabetes, and survival of persons without diabetes who have had a second myocardial infarction is similar to that of those with diabetes after an initial event (2). The prevalence at autopsy of high grade and multilevel coronary atherosclerosis in diabetic individuals without clinical coronary artery disease (CAD) is similar to that of persons without diabetes with clinical CAD, both for males and for females (3). In a French multicenter study of 417 asymptomatic diabetic persons with at least two additional risk factors undergoing thallium scintigraphy with exercise or dipyridamole, 162 had positive nuclear study, and of 70 having angiography, 39 were found to have evidence of CAD, a positive predictive value of only 56%. Other studies suggest that approximately one-third of asymptomatic persons with diabetes have a positive screening test, but that only approximately one-third of these have positive results on angiography, suggesting poor correlation between functional and morphological abnormality. Alternatively, Valensi suggested, scintigraphy may actually be more sensitive than angiography to the presence of CAD, noting that there certainly is evidence that an abnormal study is associated with …