Skin capillary circulation severely impaired in toes of patients with IDDM, with and without late diabetic complications

Abstract

We have recently shown that the skin microcirculation of toes is significantly impaired in patients with diabetes and peripheral vascular disease, and this may be one major reason why these patients are highly susceptible to developing skin ulcers. The aim of the present study was to investigate whether the skin microcirculation is impaired also in diabetic patients free from macroangiopathy. One foot in each of 20 patients with insulin-dependent diabetes was investigated: 10 patients with and 10 patients without late complications. All patients had normal arterial circulation of their lower extremities. Two groups of age- and sex-matched healthy subjects served as controls. The capillary blood cell velocity in the nailfold of the great toe was investigated by computerised videophotometric capillaroscopy, and the total microcirculation within the same area evaluated by laser Doppler fluxmetry. The capillary blood cell velocity and the total skin microcirculation were studied during rest, and during postocclusive reactive hyperaemia. The total microcirculation was similar in patients and control subjects, whereas the capillary circulation was markedly reduced (p<0.01) in the patients. The ratio between the capillary and total microcirculation was significantly decreased (p<0.05-0.01) in the patients as compared to the control subjects, indicating a local maldistribution of blood in the skin microcirculation of the diabetic patients. The results of the present study show that in spite of a normal total skin microcirculation in the toes of insulin-dependent diabetic patients, both with and without late complications, the nutritional capillary circulation is severely impaired. These findings indicate that a chronic ischaemia is present in the skin capillaries of diabetic feet, and is related to the diabetic disease per se and not to late diabetic complications, and may be a cause for these complications. © 1995 Springer-Verlag.