Skin microvascular function in patients with type 1 diabetes: An observational study from the onset of diabetes

Abstract

Background: The development of disturbances in skin microcirculation in type 1 diabetes is not well characterised. We assessed skin microcirculation longitudinally from the onset of diabetes up to 29 years of duration to investigate when such disturbances start. Material and methods: Seventeen adult patients with type 1 diabetes participated. Skin microvascular function in digit IV of the left hand was investigated by laser Doppler fluxmetry (LDF, arbitrary units [AU]). LDF was carried out at rest and following one-min arterial occlusion. Time to peak LDF (s) and percentage increase of LDF (post-occlusive reactive hyperaemia, PRH%) were determined. Retinopathy was assessed from fundus photographs or ophthalmoscopic recordings. Results: Skin microvascular function remained normal during the first five years. Compared with baseline and a non-diabetic reference group, time to peak LDF was prolonged after 7–9 years of diabetes ( p < 0.01). PRH% was lower than in the reference group after 7–9 years ( p < 0.01), and lower than baseline after 24–29 years of diabetes ( p < 0.05). All but one patient developed retinopathy and the first signs were found after 10 years of diabetes. Conclusions: Functional disturbances in total skin microcirculation were observed after seven years in patients with type 1 diabetes and preceded diabetic complications such as retinopathy.