title: Correlation between diabetic retinopathy severity and elevated skin autofluorescence as a marker of advanced glycation end-product accumulation in type 2 diabetic patients.
abstract: OBJECTIVE
  We evaluated skin autofluorescence (AF) as a marker of tissue advanced glycation end-product (AGE) accumulation and examined whether it was related to the prevalence and severity of diabetic retinopathy (DR) and of diabetic macular edema (DME) in patients with type 2 diabetes mellitus (DM).
  
  
  METHODS
  This study included 138 type 2 DM patients consisting of 31 patients with proliferative DR, 71 patients with non-proliferative DR, and 36 patients without retinopathy, in addition to 111 non-DM control subjects. At the time of skin AF and HbA1c measurement, self-assessed duration of DM was also determined. DR and DME stages were classified according to international guidelines.
  
  
  RESULTS
  Skin AF was significantly increased in patients with DM as compared with non-DM controls. Furthermore, skin AF was correlated with the severity of DR, whereas single measurement of HbA1c and self-assessed DM duration were not. None of these 3 factors showed a correlation with DME prevalence or severity.
  
  
  CONCLUSIONS
  Skin AF levels, which can be measured non-invasively on a screening basis without skin biopsy or blood sampling, have a greater predictive ability for the presence and severity of DR than single measurement of HbA1c or self-assessed DM duration in patients with type 2 DM.
authors.affiliation: Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, Japan; Omachi Municipal General Hospital, Omachi, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Hirano
authors.affiliation: Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Iesato
authors.affiliation: Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Toriyama
authors.affiliation: Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Imai
authors.affiliation: Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, Japan; Omachi Municipal General Hospital, Omachi, Japan.
authors.forename: Dai
authors.initials: D
authors.lastname: Chiba
authors.affiliation: Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, Japan. Electronic address: murata@shinshu-u.ac.jp.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Murata
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D005453:Fluorescence; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D011379:Prognosis; D012720:Severity of Illness Index; D012867:Skin / Q000378:metabolism / Q000503:physiopathology*
chemical_list: D015415:Biomarkers; D017127:Glycation End Products, Advanced
keywords: Advanced glycation end-product; Diabetic macular edema; Diabetic retinopathy; Skin autofluorescence; Type 2 diabetes mellitus; Vascular endothelial growth factor