Purpose: The primary objective was to evaluate the prevalence of atherosclerotic disease, myocardial infarctions, and cerebrovascular disease in patients with long-standing diabetes using whole-body magnetic resonance imaging (WB-MRI) combined with whole-body magnetic resonance angiography (WB-MRA) and to estimate the cumulative disease burden in a new MRA-based score.
Materials and methods: The study was approved by the ethics committee and all patients gave informed written consent. Sixty-five patients with long-standing (>10 years) diabetes mellitus without acute symptoms were prospectively evaluated. The patients were clinically assessed and received WB-MRI/WB-MRA containing an examination of the brain, the heart, the arterial vessels (abdominal aorta, the supraaortic, renal, pelvic, and peripheral arteries), and the feet. Prevalence rates were calculated and compared with a healthy control group of 200 individuals after adjustment for age and sex by a logistic regression analysis using exact parameter estimates (Cochran-Mantel-Haenszel-statistics). Finally, an MRA based vessel score (sum of grades of all evaluated vessels divided by the number of vessels; grades range from 1, normal, to 6, complete occlusion) indicative of atherosclerotic disease burden was created for this study. This vessel score's association with clinical and biochemical parameters (age, sex, type of diabetes, diabetes duration, body mass index, blood pressure, smoking, coronary artery disease-status, retinopathy, serum creatinine, hemoglobin A1c test, low density lipoprotein-concentration, medication) was assessed with an age and sex adjusted analysis (generalized linear model).
Results: In the diabetic patients, we found prevalence rates of 49% for peripheral artery disease, 25% for myocardial infarction, 28% for cerebrovascular disease, and 22% for neuropathic foot disease. In all vascular beds, at least 50% of the pathologies were previously unknown. Myocardial infarction (P= 0.0002), chronic ischemic cerebral lesions (P = 0.0008), and atherosclerotic disease were significantly more common in diabetic than in control subjects (internal carotid artery: P = 0.006, vertebral artery: P = 0.009, intracerebral vessels: P = 0.02, superficial femoral artery: P = 0.006, anterior tibial artery: P = 0.01, posterior tibial artery: P = 0.02, fibular artery: 0.003). The WB-MRI/WB-MRA-based score showed a significant association with age (P = 0.0008), male sex (P = 0.03), nephropathy (P = 0.006), diabetic retinopathy (P = 0.007), and coronary artery disease status (P = 0.006). Body mass index, blood pressure, hemoglobin A1c test, low density lipoprotein-cholesterol, and medications showed no significant association with the score.
Conclusions: Using WB-MRI combined with WB-MRA we found a high prevalence of occult atherosclerotic disease in long-standing diabetic patients. This study shows that the true atherosclerotic burden in these patients is largely underestimated.