title: A minimally invasive system for glucose area under the curve measurement using interstitial fluid extraction technology: evaluation of the accuracy and usefulness with oral glucose tolerance tests in subjects with and without diabetes.
abstract: BACKGROUND
  Recent studies have highlighted the importance of managing postprandial hyperglycemia, but adequate monitoring of postprandial glucose remains difficult because of wide variations in levels. We have therefore developed a minimally invasive system to monitor postprandial glucose area under the curve (AUC). This system involves no blood sampling and uses interstitial fluid glucose (IG) AUC (IG-AUC) as a surrogate marker of postprandial glucose. This study aimed to evaluate the usefulness of this system by comparing data with the findings of oral glucose tolerance tests (OGTTs) in subjects with and without diabetes.
  
  
  METHODS
  The glucose AUC monitoring system was validated by OGTTs in 37 subjects with and 10 subjects without diabetes. A plastic microneedle array was stamped on the forearm to extract IG. A hydrogel patch was then placed on the pretreated area to accumulate IG. Glucose and sodium ion concentrations in the hydrogel were measured to calculate IG-AUC at 2-h postload glucose. Plasma glucose (PG) levels were measured every 30 min to calculate reference PG-AUC.
  
  
  RESULTS
  IG-AUC correlated strongly with reference PG-AUC (r=0.93) over a wide range. The level of correlation between IG-AUC and maximum PG level was also high (r=0.86). The painless nature of the technique was confirmed by the response of patients to questionnaires.
  
  
  CONCLUSIONS
  The glucose AUC monitoring system using IG provided good estimates of reference PG-AUC and maximum PG level during OGTTs in subjects with and without diabetes. This system provides easy-to-use monitoring of glucose AUC, which is a good indicator of postprandial glucose.
authors.affiliation: Division of Diabetes, Metabolism and Endocrinology, Kobe University Graduate School of Medicine, Kobe, Japan. kzhkskgc@med.kobe-u.ac.jp
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sakaguchi
authors.forename: Yushi
authors.initials: Y
authors.lastname: Hirota
authors.forename: Naoko
authors.initials: N
authors.lastname: Hashimoto
authors.forename: Wataru
authors.initials: W
authors.lastname: Ogawa
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Sato
authors.forename: Seiki
authors.initials: S
authors.lastname: Okada
authors.forename: Kei
authors.initials: K
authors.lastname: Hagino
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Asakura
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kikkawa
authors.forename: Junko
authors.initials: J
authors.lastname: Kojima
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Maekawa
authors.forename: Hiromu
authors.initials: H
authors.lastname: Nakajima
mesh_terms: D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000188:drug therapy; D045604:Extracellular Fluid / Q000378:metabolism*; D005215:Fasting / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods*; D006801:Humans; D006943:Hyperglycemia / Q000097:blood*; D007328:Insulin / Q000097:blood; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D019518:Postprandial Period; D011795:Surveys and Questionnaires
chemical_list: D001786:Blood Glucose; D007328:Insulin