title: The effect of blood glucose regulation on retinal nerve fiber layer thickness in diabetic patients.
abstract: OBJECTIVE
  To evaluate the effect of blood glucose (BG) regulation on the retinal nerve fiber layer (RNFL) in diabetic patients by using a scanning laser polarimeter (NFA-GDx).
  
  
  METHODS
  We prospectively assessed RNFL thickness in diabetic patients and an age-matched control group. Patients without diabetic retinopathy, with BG >250 mg/dl, HbA1c >8%, fructosamine >285 micromol/l and triglyceride >200 mg/dl were included in the study. RNFL assessment was performed before and after metabolic regulation of diabetes. Symmetry, superior maximum, ellipse modulation and the average thickness variables of NFA-GDx were used for the assessment. Mann-Whitney U and Wilcoxon tests were used for the statistical analysis.
  
  
  RESULTS
  A total of 40 diabetic patients were included in the study and a repeat RNFL examination could be performed in 22 of them following regulation of BG levels. None of the GDx variables were significantly different between pre- and postregulation measurements (p > 0.05, Wilcoxon test). The mean superior maximum, ellipse modulation and average thickness values of the diabetic group were significantly lower than the control group (p < 0.05, Mann-Whitney U-test).
  
  
  CONCLUSIONS
  Poor metabolic control of diabetes mellitus adversely affects the thickness of RNFL and this effect does not seem to be acute since it was not reversed by short-term BG regulation. This issue needs to be kept in mind when assessing glaucomatous progress in diabetic patients.
authors.affiliation: School of Medicine, Gazi University, Ankara, Turkey.
authors.forename: Yildiz H
authors.initials: YH
authors.lastname: Lonneville
authors.forename: Sengül C
authors.initials: SC
authors.lastname: Ozdek
authors.forename: Merih
authors.initials: M
authors.lastname: Onol
authors.forename: Ilhan
authors.initials: I
authors.lastname: Yetkin
authors.forename: Gökhan
authors.initials: G
authors.lastname: Gürelik
authors.forename: Berati
authors.initials: B
authors.lastname: Hasanreisoğlu
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000378:metabolism* / Q000473:pathology; D003930:Diabetic Retinopathy; D005260:Female; D019270:Fructosamine / Q000097:blood; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009900:Optic Nerve / Q000473:pathology*; D011446:Prospective Studies; D012165:Retinal Ganglion Cells / Q000473:pathology*; D014280:Triglycerides / Q000097:blood; D058609:Visual Field Tests / Q000379:methods
chemical_list: D001786:Blood Glucose; D019270:Fructosamine; D006442:Glycated Hemoglobin; D014280:Triglycerides