Plasmatic nitric oxide, but not von Willebrand Factor, is an early marker of endothelial damage, in type 1 diabetes mellitus patients without microvascular complications

Type 1 diabetes mellitus (IDDM) is associated with coronary artery disease and microvascular damage. Long-term glycemic control reduces but not fully prevents such complications. Recent evidence suggests that microvascular disease associated to IDDM begins with endothelial dysfunction. In this study, we evaluated changes in levels of nitric oxide (NO) and von Willebrand Factor (vWF) to detect early endothelial dysfunction in IDDM patients recently diagnosed. Subjects were included in one of the following groups: Group 1 (n = 14): healthy subjects; Group 2 (n = 14): IDDM patients recently diagnosed (< 1 year), with no clinical evidence of microvascular disease; Group 3 (n = 14): IDDM patients with microvascular disease (retinopathy and nephropathy). Urinary NO metabolites were similar in Group 1 (1.45+/-0.13) and Group 2 (1.6+/-0.2 mumol/mg creatinine) (P > .05), as well as vWF (99.6+/-5.7% and 84.3+/-5.1%, Groups 1 and 2, respectively, P > .05). Plasmatic NO metabolites were lower in Groups 2 and 3 (54.6+/-5.1 and 50.02+/-13.65 nrnol/ml, respectively) compared with Group 1 (91.1+/-6.6nmol/rnI) (P = .0005). Also, in Group 3, urinary NO metabolites were lower (0.27+/-0.03 mumol/mg creatinine) and vWF was higher (184+/-25%) than Groups 1 and 2. There is evidence of early endothelial dysfunction even in IDDM patients recently diagnosed, with good glycemic control and without systemic hypertension, dislipidemia or microvascular disease; this endothelial damage was detected as a decrease in plasmatic NO metabolite levels, before appearance of any clinical evidence of microvascular disease. (C) 2003 Elsevier Inc. All rights reserved.