Accuracy of the FreeStyle Method: Measuring Blood-Glucose by Skin-Prick Blood Extraction From Forearm

經由手臂採血施行自我血糖監測之準確性

陳榮興(Rong-Hsing Chen) ； 陳清助(Chin-Chu Chen) ； 王子源(Tzu-Yuan Wang) ； 簡誌銘(Chih-Ming Chien) ； 張淳堆(Chwen-Tzuei Chang)

《Mid-Taiwan Journal of Medicine》 8卷4期 (2003/11) Pp. 214-224

https://doi.org/10.6558/MTJM.2003.8(4).5

摘要

目的　經由手指採血做自我血糖監測雖然夠準確，但由於較疼痛，常不被病人接受，為了加強糖尿病人施行自我血糖監測的意願，一種新的血糖機經由較不疼痛的部位（手臂）採血，已經被開發出來了，這篇研究的目的即在於評估這種血糖機－利舒坦(FreeStyle)的準確性。
方法　從門診收集93位空腹和93位非空腹的糖尿病病人，先抽取靜脈血，以標準的檢驗室方法檢測其血漿糖值，隨後再分別手指和手臂上採血，用三種不同的血糖機：易你測(Glucometer Elite)、固可全(Glucotrend 2)及利舒坦(FreeStyle)檢測其血糖值，再將血糖機得到的數值和檢驗的結果做比對：統計學上的準確性是以簡單線性迴歸的方法及相對標準偏差做分析，而臨床上的準確性則以Error grid analysis(EGA)做評估。每位病人並同時詢問關於在手指和手臂上採血的疼痛度。
結果　在空腹的病人，以簡單線性回歸分析顯示利舒坦的結果為：截距－9.87毫克／百毫升，斜率0.96和相關係數0.966，Error grid analysis則顯示利舒坦的測值均落於臨床上可接受的A區和B區；至於非空腹的病人，其結果為：截距26.41毫克／百毫升，斜率0.81和相關係數0.938，而有81％、17％和2％的檢測值分別落於A區、B區和D區。利舒坦的相對標準偏差值與易你測、固可全及檢驗室方法得到的結果相近。大約有97％的病人認為在手臂上採血比在手指上採血較不疼痛。
結論　利用新的血糖機－利舒坦在手臂上採血做血糖檢測，其準確性是足夠的，可以推薦給糖尿病病人做自我血糖監測。不過，由於其偵測低血糖的能力有潛在的瑕疵，而且血糖值變動較大時，其準確度亦會降低，因此在使用時仍須小心。

關鍵字

準確性 ； 血糖機 ； error grid analysis(EGA) ； 利舒坦 ； 自我血糖監測

並列摘要

Objectives. Self-measurement of blood glucose levels by the established monitoring systems is accurate but not readily accepted by patients because the finger prick is painful. A new system which involves blood sample collecting at an alternative and less painful site, the forearm, has been developed to facilitate frequent blood glucose measurement. The purpose of this study was to evaluate the accuracy of this new blood glucose monitoring system: the FreeStyle method.
Methods. Venous blood samples were drawn from 93 fasting and 93 nonfasting outpatients with diabetes. Plasma was extracted by a standard laboratory method for glucose measurement. Capillary blood was then obtained from each patient by skin prick on the fingertip and forearm. Blood glucose was measured by two standard blood glucose meters, the Glucometer Elite and the Glucotrend 2, and the FreeStyle system. The data were compared with a reference laboratory method. Each patient was also asked to comment on the pain associated with the skin prick at both sites. The accuracy of self-monitoring systems was evaluated by statistical and clinical analyses.
Results. Linear regression analysis of the FreeStyle data from fasting patients revealed an
intercept of 9.87 mg/dL, a slope of 0.96, and a correlation coefficient (r) of 0.966. Furthermore, error grid analysis (EGA) demonstrated that all of the data fell within zones A (81%) and B (19%), which define clinically acceptable results. Linear regression analysis of the FreeStyle data from nonfasting subjects revealed an intercept of 26.41 mg/dL, a slope of 0.81, and a correlation coefficient (r) of 0.938. EGA revealed that 81% of the data fell within zone A, 17% within zone B and 2% within zone D. The relative standard deviation (RSD) for FreeStyle was similar to the RSD for the two standard meters and the reference laboratory method. Ninety-seven percent of the patients reported that they experienced less pain from the forearm skin prick than from skin prick at the fingertip.
Conclusions. The FreeStyle blood glucose monitoring system which requires forearm skin prick for blood extraction is sufficiently accurate for home use. However, caution must be taken because of its potential failure to detect hypoglycemia and because the accuracy is reduced during rapid change of blood glucose levels.

並列關鍵字

accuracy ； blood glucose meter ； error grid analysis (EGA) ； FreeStyle ； self-monitoring of blood glucose(SMBG)