quarta-feira, março 04, 2009
CONGRESSO ADA 2009 - TEMA LIVRE
Carotid plaque is more frequent, but not related to intima-media tickness in asymptomatic type 2 diabetic subjects.
Jose Roberto Matos Souza, Daniela Schiavo, Otavio Rizzi Coelho, Marcos Antonio Tambascia, Ademar Yamanaka, Bruno Geloneze.
Atherosclerosis develops over the course of several years, beginning in the early teenage years, and accelerating in the presence of type 2 diabetes. This process occurs due to a lipid retention, oxidation, and modification, which provoke chronic inflammation at susceptible sites in the walls of all major conduit arteries, including the carotids. Ultrasound measurements of intima-media thickness (IMT) and plaque occurrence in the carotid arteries are important not only for the assessment of structural alterations but also because the extent of atherosclerosis in these vessels reflects the severity of arterial damage in other vascular territories.
Aims and Methods: To describe the findings of a carotid artery study including the measurement of IMT, the presence of atherosclerotic plaque, and their correlation with the presence of type 2 diabetes in asymptomatic subjects.
Two hundred ninety two patients (220 non-diabetics and 72 Type 2 diabetics; age 55(8) years) selected from Metabolic Syndrome outpatient clinic of University of Campinas Medical Hospital who underwent a carotid artery ultrasound in our Doppler vascular laboratory were screened for carotid plaque and IMT measurement. Type 2 diabetics (DM) and Non-diabetics (nDM) groups showed no differences in age: 56(8) vs. 54(9) y, gender (male: 62 vs. 66%), presence of hypertension (88 vs. 84%), dyslipidemia (66 vs. 58%), smoking (15 vs. 20%), use of ACE inhibitors (88 vs. 78%). Diabetics subjects were taking aspirin and statins in 98 and 82%, respectively, in comparison to 1 and 42% in nDM group (p<0.01). Measurements were made with a high-resolution B-mode ultrasonography (Shimadzu SDU-1200 - Kioto, Japan) with a linear 7.5-10 MHz. transducer. Sonography and readings were carried out by trained and certified sonographers. Measurements of IMT were take at 20 mm before bifurcation of both right and left common carotid artery in the far wall. An artery was classified as being affected by plaque if there was a localized thickening > 2.0 mm that did not uniformly involve the whole left or right carotid artery with or without flow disturbance.
Results: IMT was greater in DM group [1.014(0.018) vs. 0.690(0.006) mm, p<0.001]. The presence of atherosclerotic plaques was 19.4% in DM, and 1.4% in nonDM asymptomatic subjects (p<0.001). In the DM group, patients with plaques showed similar IMT measurements to patients without plaques [1.030(0.038) vs. 1.009(0.020) mm]
Conclusions: Assessment of carotid arteries identified increased incidence of atherosclerotic plaque in Type 2 diabetic patients without symptomatic CAD. IMT was increased in diabetics independent of the presence of the plaque.