Abstract

BACKGROUND
Although diabetic microangiopathy has its greatest clinical effects in the retina, kidneys and nerves there is much evidence that the process is generalized, and that these lesions involve most capillary beds. However, the potential relationship between the presence of diabetic neuropathy, and/or retinopathy, and skin blood flow has not been fully evaluated. Therefore we measured the cutaneous blood flow in diabetics, both with and without microangiopathy, to determine the relationship between microangiopathy and the cutaneous blood flow. METHODS: One hundred-and nineteen type 2 diabetic patients were classified into four categories, based on the presence of polyneuropathy or retinopathy. The skin blood flow was measured in the diabetic patients with or without neuropathy and retinopathy, before, during and after exposure to cold. Before, during and 1 min after the application of a cold-pack, skin blood flow measurements were performed using a laser Doppler techniques at the following right-sided locations: (1) the dorsum of the wrist and ankle, as nutritive microvasculatures, and (2) the pulp of tip of the index finger and big toe, as themoregulatory ones. RESULTS: During the 1-min cold applications, the percentage changes in the decrement of the skin blood flow, at the 4 skin sites, showed decreasing trends in the neuropathy group. However, the differences in the diabetics with neuropathy were not significantly greater than in those without neuropathy. The changes at the same sites in the group with retinopathy were similar to those with neuropathy. The percentage changes in the increment of the skin blood flow were measured at the 4 skin sites 1 min after exposure to cold, and also showed a blunted tendency in both the diabetic neuropathy and retinopathy groups. The percentage changes in the flow increment at the pulp of the big toe were greater in the diabetics without neuropathy or retinopathy, compared to those with these complications (p<0.05). CONCLUSION: These results suggest that changes in the cutaneous blood flow would be more predominant at the thermoregulatory vasculature sites in the type 2 diabetics with neuropathy or retinopathy, and seems to be related to diabetic microangiopathy.

• Keywords: Cutaneous blood flow;Type 2 diabetes;Neuropathy;Retinopathy;