title: Impaired retinal circulation in patients with type 2 diabetes mellitus: retinal laser Doppler velocimetry study.
abstract: OBJECTIVE
  To evaluate the differences in retinal circulation in eyes of patients with type 2 diabetes with no or early-stage diabetic retinopathy compared with control eyes.
  
  
  METHODS
  Seventy-five nondiabetic eyes and 194 eyes with type 2 diabetes mellitus were evaluated. The type 2 diabetic eyes were classified into two groups: 139 eyes (139 patients) without diabetic retinopathy (NDR) and 55 eyes (55 patients) with mild nonproliferative diabetic retinopathy (NPDR). The retinal circulatory parameters were measured with laser Doppler velocimetry, and the factors that affect retinal hemodynamics were determined in a cross-sectional population of patients with type 2 diabetes.
  
  
  RESULTS
  The group-averaged blood velocity (V) and retinal blood flow (RBF) in the NDR and mild NPDR groups were significantly (P < 0.01) lower than in the non-DM group. The diameter and wall shear rate were also significantly (P < 0.05) lower in the NDR group than in the nondiabetic control eyes. Multiple regression analysis showed that the RBF was independently and negatively correlated with serum low-density lipoprotein and creatinine. HbA1c was significantly (P < 0.05) higher in participants in the lowest RBF quartile than in the highest quartiles.
  
  
  CONCLUSIONS
  The results indicate that the RBF may decrease in patients with type 2 diabetes without retinopathy and in those with mild retinopathy.
authors.affiliation: Department of Ophthalmology, Asahikawa Medical College, Asahikawa, Japan. nagaoka@asahikawa-med.ac.jp
authors.forename: Taiji
authors.initials: T
authors.lastname: Nagaoka
authors.forename: Eiichi
authors.initials: E
authors.lastname: Sato
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takahashi
authors.forename: Harumasa
authors.initials: H
authors.lastname: Yokota
authors.forename: Kenji
authors.initials: K
authors.lastname: Sogawa
authors.forename: Akitoshi
authors.initials: A
authors.lastname: Yoshida
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001775:Blood Circulation / Q000502:physiology; D001783:Blood Flow Velocity; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000097:blood / Q000503:physiopathology*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D017078:Laser-Doppler Flowmetry; D008077:Lipoproteins, LDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D012161:Retinal Artery / Q000503:physiopathology*
chemical_list: D001786:Blood Glucose; D003404:Creatinine; D006442:Glycated Hemoglobin; D008077:Lipoproteins, LDL; C517652:hemoglobin A1c protein, human