Comparison of skin microvascular reactivity with hemostatic markers of endothelial dysfunction and damage in type 2 diabetes

Sandra Beer^1,2, François Feihl¹, Juan Ruiz², Irène Juhan-Vague³, Marie-Françoise Aillaud³, Sandrine Golay Wetzel¹, Lucas Liaudet⁴, Rolf C Gaillard², Bernard Waeber¹

Centre Hospitalier Universitaire Vaudois, Division de Physiopathologie Clinique, Lausanne, Suisse

¹Division de Physiopathologie Clinique, Centre Hospitalier Universitaire Vaudois et Université de Lausanne, Lausanne, Suisse; ²Service d’Endocrinologie, de Diabétologie et de Métabolisme, Centre Hospitalier Universitaire Vaudois et Université de Lausanne, Lausanne, Suisse; ³Laboratoire d’hématologie, Centre Hospitalier Universitaire de Marseille; Inserm UMR 626, Marseille, France; ⁴Service de Médecine Intensive de l’Adulte, Centre Hospitalier Universitaire Vaudois et Université de Lausanne, Lausanne, Suisse

Aim: Patients with non-insulin-dependent diabetes mellitus (NIDDM) are at increased cardiovascular risk due to an accelerated atherosclerotic process. The present study aimed to compare skin microvascular function, pulse wave velocity (PWV), and a variety of hemostatic markers of endothelium injury [von Willebrand factor (vWF), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA), tissue factor pathway inhibitor (TFPI), and the soluble form of thrombomodulin (s-TM)] patients with NIDDM.

Methods: 54 patients with NIDDM and 38 sex- and age-matched controls were studied. 27 diabetics had no overt micro- and/or macrovascular complications, while the remainder had either or both. The forearm skin blood flow was assessed by laser-Doppler imaging, which allowed the measurement of the response to iontophoretically applied acetylcholine (endotheliumdependent vasodilation) and sodium nitroprusside (endothelium-independent vasodilation), as well as the reactive hyperemia triggered by the transient occlusion of the circulation.

Results: Both endothelial and non-endothelial reactivity were significantly blunted in diabetics, regardless of the presence or the absence of vascular complications. Plasma vWF, TFPI and s-TM levels were significantly increased compared with controls only in patients exhibiting vascular complications. Concentrations of t-PA and PAI-1 were significantly increased in the two groups of diabetics versus controls.

Conclusion: In NIDDM, both endothelium-dependent and -independent microvascular skin reactivity are impaired, whether or not underlying vascular complications exist. It also appears that microvascular endothelial dysfunction is not necessarily associated in NIDDM with increased circulating levels of hemostatic markers of endothelial damage known to reflect a hypercoagulable state.

Keywords: skin microcirculation, iontophoresis, pulse wave velocity, type 2 diabetes, hemostatic markers