Delayed vascular reactivity to ischemia in diabetic microangiopathy.
To investigate vascular responses in insulin-dependent diabetic patients both with and without retinopathy, we have assessed vasodilation by forearm transcutaneous pO2 measurement after 10 min of ischemia produced by a sphygmomanometer cuff. Diabetic patients with proliferative retinopathy had a delayed vasodilatory response at 60 s (mean +/- SD pO2 = 9 +/- 3 mm Hg) compared with those having diabetes without retinopathy (15 +/- 4 mm Hg, P less than 0.01) and matched normal subjects (14 +/- 4 mm Hg, P less than 0.01). Recently diagnosed insulin-dependent diabetic patients had a very similar response (15 +/- 5 mm Hg) to matched normal subjects (15 +/- 3 mm Hg). The diminished vascular reactivity may be a consequence of microangiopathy and neuropathy, although patients with an impaired vascular response might be particularly at risk from the development of capillary closure.
D000328:Adult; D001132:Arm / Q000098:blood supply; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000503:physiopathology; D005260:Female; D006801:Humans; D007511:Ischemia / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D013997:Time Factors; D014664:Vasodilation