title: Variability of skin autofluorescence measurement over 6 and 12 weeks and the influence of benfotiamine treatment.
abstract: BACKGROUND
  Measurements of skin autofluorescence (SAF) allow for a simple and noninvasive quantification of tissue advanced glycation end-products (AGEs), a marker linked to the risk of diabetes complications. The aim of this study was to test the repeatability of SAF over 6 and 12 weeks and to test whether benfotiamine, a thiamine prodrug suggested to reduce AGEs formation under hyperglycemic conditions, is able to attenuate SAF when administered over 6 weeks.
  
  
  METHODS
  In a double-blind, placebo-controlled, randomized, crossover study, 22 patients with type 2 diabetes mellitus (T2DM) received 900 mg/day benfotiamine or placebo for 6 weeks (washout period of 6 weeks between). At the beginning and at the end of each treatment period, SAF was assessed in the fasting state, as well as 2, 4, and 6 h following a mixed test meal.
  
  
  RESULTS
  The respective intra-individual and inter-individual variability of fasting SAF was 6.9% and 24.5% within 6 weeks and 10.9% and 23.1% within 12 weeks. The respective variability calculated for triplicate comparisons was 9.9% and 27.7%. A short-term therapy with benfotiamine did not influence SAF significantly, nor did we find a significant postprandial SAF increase.
  
  
  CONCLUSIONS
  In patients with T2DM, repeated, timely spaced SAF measurements have an intra-subject variability of below 11%. Using these data, sample sizes were calculated for interventional studies aiming at reducing SAF. Benfotiamine treatment for 6 weeks did not significantly influence SAF; for this, a longer-term therapy is probably needed.
authors: Diabetes Clinic, Heart and Diabetes Center NR, Ruhr University Bochum, Bad Oeynhausen, Germany. alin.stirban@profil.com
authors: Alin
authors: A
authors: Stirban
authors: Alexandra
authors: A
authors: Pop
authors: Annelie
authors: A
authors: Fischer
authors: Sascha
authors: S
authors: Heckermann
authors: Diethelm
authors: D
authors: Tschoepe
mesh_terms: D000328:Adult; D000368:Aged; D002614:Chelating Agents / Q000627:therapeutic use*; D018592:Cross-Over Studies; D048909:Diabetes Complications / Q000175:diagnosis* / Q000188:drug therapy*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy; D004311:Double-Blind Method; D005260:Female; D005453:Fluorescence; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000097:blood; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000502:physiology; D015203:Reproducibility of Results; D012867:Skin / Q000187:drug effects*; D013831:Thiamine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D002614:Chelating Agents; D017127:Glycation End Products, Advanced; D013831:Thiamine; C013835:benphothiamine