[Study on risk factors of tissue hypoxia in patients with diabetic retinopathy]

Risk factors of tissue hypoxia was investigated in 26 patients with diabetic retinopathy (DMR), who compared with 62 patients without DMR. significant higher incidence of DMR was found in patients with poor diabetic control (HbA 1 greater than or equal to 10%), with orthostatic hypotension (OH), with peripheral neuropathy and with atherosclerosis respectively. Erythrocyte 2,3-diphosphoglycerate (2,3-DPG) was lower (P less than 0.05) and venous oxygen tension in pedal dorsum (PvO2) higher (P less than 0.05) in DMR patients than those in uncomplicated DMR patients and normal subjects. There was a rank correlation between DMR severity and PvO2 (r = 0.429, P less than 0.05), which imply that decreased blood oxygen utilization may be related to diabetic microangiopathy. These data suggested that abnormal changes of HbA 1 and 2,3-DPG, decrease of peripheral blood oxygen utilization, atherosclerosis, OH and neuropathy might be risk factors of tissue hypoxia in DMR patients.