Accuracy of a Novel “Factory-Calibrated” Continuous Glucose Monitoring Device in Normal Glucose Levels: A Pilot Study
Volume 3, Issue 6, November 2017, Pages: 109-113
Received: Sep. 12, 2017;
Accepted: Sep. 30, 2017;
Published: Oct. 23, 2017
Views 2501 Downloads 128
Takashi Murata, Diabetes Center, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
Shinsuke Nirengi, Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
Yaeko Kawaguchi, Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
Shin Sukino, Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
Tomokazu Watanabe, Diabetes Center, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
Naoki Sakane, Division of Preventive Medicine, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
Free Style Libre Pro, a novel continuous glucose monitoring (CGM) device for retrospective assessment of glycemic excursion, does not require calibration during the measurement period. In this study, the accuracy of FreeStyle Libre Pro in normal glucose levels was investigated. Two meal tests, on the 7th day and 9th day of CGM usage, were performed in five non-diabetic adults. Venous blood samples were obtained at baseline, and at 2 hours, 4 hours and 6 hours after the meal. The plasma glucose levels and the glucose levels measured by FreeStyle Libre Pro were compared. Subjects were aged 41.4±7.6 years, 40% male, with body mass index 21.7±2.6, HbA1c 5.6±0.3% and a fasting plasma glucose level of 95.4±2.1 mg/dl. The plasma glucose levels and the glucose levels measured by FreeStyle Libre Pro were significantly different; 94.4±1.8 vs. 111.2±8.5 mg/dl (P <0.01) at baseline, 95.6±7.0 vs. 122.6±8.8 mg/dl (P <0.01) at 2 hours, 90.1±4.3 vs. 111.2±13.0 mg/dl (P <0.01) at 4 hours, and 88.7±3.2 vs. 105.5±7.1 mg/dl (P <0.01) at 6 hours. The absolute difference between the two methods was 17.7±7.5 (minimum 5 - maximum 27) mg/dl at baseline, 27.0±9.4 (minimum 8 - maximum 40) mg/dl at 2 hours, 21.1±11.3 (minimum 7 - maximum 42) mg/dl at 4 hours, 16.8±5.4 (minimum 7 - maximum 23) mg/dl at 6 hours, and 20.7±9.3 (minimum 5 - maximum 42) mg/dl for all time points, respectively. The absolute relative difference between them was 18.7±7.8 (minimum 5.3 - maximum 28.7)% at baseline, 28.7±10.7 (minimum 7.7 - maximum 45.5)% at 2 hours, 23.3±12.2 (minimum 7.9 - maximum 45.2)% at 4 hours, 18.9±6.0 (minimum 8.0 - maximum 26.2)% at 6 hours, and 22.4±10.0 (minimum 5.3 - maximum 43.5)% for all time points, respectively. The ratio of values measured by FreeStyle Libre Pro within the interval of ±15 mg/dl in less than 100 mg/dl or within the interval of ±15% in not less than 100 mg/dl plasma glucose levels was 30.0% at baseline, 10.0% at 2 hours, 40.0% at 4 hours, 50.0% at 6 hours and 32.5% for all time points, respectively. These study results suggest FreeStyle Libre Pro may not be sufficiently accurate in normal glucose levels.
Accuracy of a Novel “Factory-Calibrated” Continuous Glucose Monitoring Device in Normal Glucose Levels: A Pilot Study, Biomedical Sciences.
Vol. 3, No. 6,
2017, pp. 109-113.
K. Benkhadra, F. Alahdab, S. Tamhane, Z. Wang, L. K. Prokop, I. B. Hirsch, D. Raccah, J. P. Riveline, O. Kordonouri, and M. H. Murad, “Real-time continuous glucose monitoring in type 1 diabetes: a systematic review and individual patient data meta-analysis,” Clin. Endocrinol. (Oxf), vol. 86(3), pp. 354-360, March 2017.
M. Langendam, Y. M. Luijf, L. Hooft, J. H. Devries, A. H. Mudde, and R. J. Scholten, “Continuous glucose monitoring systems for type 1 diabetes mellitus,” Cochrane Database Syst. Rev., 1, CD008101, Jan 2012.
D. Rodbard, "Continuous Glucose Monitoring: A Review of Successes, Challenges, and Opportunities,” Diabetes. Technol. Ther., vol. 18 (S2), pp. S3-S13, February 2016.
E. J. Fogt, L. M. Dodd, E. M. Jenning, and A. H. Clemens, “Development and evaluation of a glucose analyzer for a glucose controlled insulin infusion system (Biostator),” Clin. Chem., vol. 24(8), pp. 1366-1372, August 1978.
Diabetes Control and Complications Trial Research Group, “The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes mellitus,” N. Engl. J. Med., Vol. 329(14), pp. 977-86, September 1993.
UK Prospective Diabetes Study (UKPDS) Group, “Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33),” Lancet, vol. 352(9131), pp 837-53, September 1998.
G. Freckmann, C. Schmid, A. Baumstark, M. Rutschmann, C. Haug, and L. Heinemann, “Analytical Performance Requirements for Systems for Self-Monitoring of Blood Glucose With Focus on System Accuracy: Relevant Differences Among ISO 15197:2003, ISO 15197:2013, and Current FDA Recommendations”, J. Diabetes. Sci. Technol., vol. 9(4), pp. 885-94, July 2015.
J. L. Parkes, S. L. Slatin, S. Pardo, and B. H. Ginsberg, “A new consensus error grid to evaluate the clinical significance of inaccuracies in the measurement of blood glucose,” Diabetes Care, vol. 23(8), pp. 1143-8, August 2000.
A. Heller and B. Feldman, “Electrochemical Glucose Sensors and Their Applications in Diabetes Management,” Chem. Rev., vol. 108(7), pp. 2482–2505, September 2008.
A. Basu, S. Dube, S. Veettil, M. Slama, Y. C. Kudva, T. Peyser, R. E. Carter, C. Cobelli, and R. Basu, “Time Lag of Glucose From Intravascular to Interstitial Compartment in Type 1 Diabetes,” J. Diabetes Sci. Technol., vol. 9(1), pp. 63–68, January 2015.
G. Schmelzeisen-Redeker, M. Schoemaker, H. Kirchsteiger, G. Freckmann, L. Heinemann, and L. Del Re, “Time Delay of CGM Sensors: Relevance, Causes, and Countermeasures,” J. Diabetes Sci. Technol., vol. 9(5), pp. 1006-15, August 2015.
T. S. Bailey, G. Grunberger, B. W. Bode, Y. Handelsman, I. B. Hirsch, L. Jovanovič, V. L. Roberts, D. Rodbard, W. V. Tamborlane, and J. Walsh, American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE), “AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY 2016 OUTPATIENT GLUCOSE MONITORING CONSENSUS STATEMENT,” Endocr. Pract., vol. 22(2), pp. 231-61, February 2016.
R. M. Bergenstal, S. Garg, S. A. Weinzimer, B. A. Buckingham, B. W. Bode BW, W. V. Tamborlane, and F. R. Kaufman, “Safety of a Hybrid Closed-Loop Insulin Delivery System in Patients With Type 1 Diabetes,” J. A. M. A., vol. 316(13), pp. 1407-1408, October 2016.
T. Bailey, B. W. Bode, M. P. Christiansen, L. J. Klaff, and S. Alva, “The Performance and Usability of a Factory-Calibrated Flash Glucose Monitoring System,” Diabetes Technol. Ther., vol. 17(11), pp. 787-94, November 2015.
H. Udo and B. E. Satrya, “Factory-Calibrated Continuous Glucose Sensors: The Science Behind the Technology,” Diabetes Technol. Ther., vol. 19(S2), pp. S-44-S-50, May 2017.
Abbott Japan Co., Ltd., FreeStyle Libre Pro performance sheet, 2016.
Abbott Japan Co., Ltd., FreeStyle Libre performance sheet, 2015.
L. Ji, X. Guo, L. Guo, Q. Ren, N. Yu, and A. Zhang, “Multicenter Evaluation of the Performance and Usability of a Novel Glucose Monitoring System in Chinese Adults With Diabetes,” J. Diabetes Sci. Technol., vol. 11(2), pp. 290-295, March 2017.
A. F. Ólafsdóttir, S. Attvall, U. Sandgren, S. Dahlqvist, A. Pivodic, S. Skrtic, E. Theodorsson, and M. Lind, “A Clinical Trial of the Accuracy and Treatment Experience of the Flash Glucose Monitor FreeStyle Libre in Adults with Type 1 Diabetes,” Diabetes Technol. Ther., vol. 19(3), pp. 164-172, March 2017.
US Food and Drug Administration. PMA P150021: FDA Summary of Safety and Effectiveness Data. https://www.accessdata.fda.gov/cdrh_docs/pdf15/P150021B.pdf (last visited date: September 19th, 2017).
M. P. Christiansen, S. K. Garg, R. Brazg, B. W. Bode, T. S. Bailey, R. H. Slover, A. Sullivan, S. Huang, J. Shin, S. W. Lee, and F. R. Kaufman, “Accuracy of a Fourth-Generation Subcutaneous Continuous Glucose Sensor,” Diabetes Technol. Ther., vol. 19(8), August 2017.