Endothelial dysfunction and cardiovascular outcome in asymptomatic patients with type 2 diabetes: A pilot study

Background: Type 2 diabetes mellitus (T2DM) is associated with an increased risk of cardiovascular events, but risk stratification of asymptomatic T2DM patients remains a challenging issue. We conducted a pilot study to assess whether endothelial dysfunction might help identify, among asymptomatic T2DM patients, those at increased risk of cardiovascular events. Methods: We studied 61 consecutive T2DM patients with no evidence of cardiovascular disease and no insulin therapy. Endothelial function was assessed by flow-mediated dilation (FMD) of the right brachial artery. The primary endpoint was a combination of major cardiovascular events (MACE: cardiovascular death, acute coronary events, coronary interventions, and acute cerebrovascular accidents). FMD was repeated at follow-up in 48 patients (79%). Results: A total of 10 MACE (16.4%) occurred during a mean follow-up of 48 months, including three acute myocardial infarctions, five coronary revascularizations for stable angina, and two acute ischaemic strokes. FMD at enrolment was lower in patients with compared with patients without MACE (3.78 ± 0.97% vs 4.70 ± 1.33%, respectively; P =.04). No other clinical or laboratory variables (age, diabetes duration, glycated haemoglobin, cardiovascular risk factors, drug therapy, and nitrate-mediated dilation) were associated with MACE. FMD at follow-up was also lower in patients with (n = 10) compared with those without (n = 38) MACE (3.66 ± 1.29 vs 4.85 ± 1.92; P =.006). Conclusions: Our data suggest that assessment of FMD might be helpful to identify patients at increased risk of MACE among individuals with asymptomatic T2DM; accordingly, a large study is warranted to adequately define the clinical utility of FMD assessment in the management of T2DM patients.