Comparison of Noninvasive Blood Glucose Concentrations Relative to Finger Capillary Blood Glucose References

• Calibrate near-infrared spectroscopy-based glucose meter [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  The collection of capillary blood glucose and noninvasive data will allow the calibration of the noninvasive systems and subsequently evaluate performance via a validation study. The paired NIR spectrum and blood reference data acquired during calibration will be processed using multivariate regression techniques to create a calibration model. Results will be compared using a Clark error grid.
  
  

• Compare Noninvasive to invasive techniques [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  Comparison of noninvasive glucose measurement performance versus standard invasive reference. Invasive measurements are made by obtaining capillary blood glucose measurements and then measuring blood on a Yellow Springs Instrument (YSI). Due to the fact that instrumentation drift and subject physiological changes can adversely influence measurement performance, the study is specifically designed to examine performance over an appropriate period of time with a reasonable distribution of subject variance. Results will be compared using a Clark error grid.
  
  

Currently, individuals with diabetes must use an invasive finger stick methodology for the determination of their blood glucose levels. Although current technology glucose meters use a smaller amount of blood than older generation meters, the pain and inconvenience associated with this invasive measurement is the number one reason cited for inadequate or infrequent blood glucose monitoring. In fact up to 67% of patients with diabetes fail to routinely monitor their blood glucose levels. A survey of 1895 patients showed that finger soreness was the most common reason given for self-reported noncompliance with testing recommendations, followed by pain, inconvenience, fear of needles, and "other" (including cost), (Diabetes Care August 2001 vol. 24 no. 8 1502-1503). The ability to make a painless blood glucose measurement using only light would address the pain and inconvenience issues associated with current technology glucose meters.

The initial application of the technology is associated with the monitoring of Gestational Diabetes. The International Association of Diabetes and Pregnancy Study Groups (IADPSG) recently released recommendations for diagnosing gestational diabetes, as well as clarifying the benefits of treatment (Diabetes Care, 2010;33:676-682). The IADPSG cited research that found significant graded relationships between increasing maternal glucose levels and the frequency of four primary and five secondary outcomes. For example, with a 1-standard deviation increase in maternal fasting, 1-hour, and 2-hour plasma glucose levels, there was a corresponding 38%, 46%, and 38% increased risk, respectively, in the primary outcome of birth weight >90th percentile, and a 5%, 18%, and 16% increased risk, respectively, of the secondary outcome of premature delivery before 37 weeks gestation (N Engl J Med 2008;358:1991-2002).