Division of Endocrinology and Nuclear Medicine, Department of Internal Medicine, Medical University Graz, Austria.
Diabet Med. 2010 Mar;27(3):332-8. doi: 10.1111/j.1464-5491.2009.02924.x.
To compare the accuracy of two marketed subcutaneous glucose monitoring devices (Guardian RT, GRT; GlucoDay S, GDS) and standard microdialysis (CMA60; MD) in Type 1 diabetic patients.
Seven male Type diabetic patients were investigated over a period of 26 h simulating real-life meal glucose excursions. Catheters of the three systems were inserted into subcutaneous adipose tissue of the abdominal region. For MD, interstitial fluid was sampled at 30- to 60-min intervals for offline glucose determination. Reference samples were taken at 15- to 60-min intervals. All three systems were prospectively calibrated to reference. Median differences, median absolute relative differences (MARD), median absolute differences (MAD), Bland-Altman plot and Clark Error Grid were used to determine accuracy.
Bland-Altman analysis indicated a mean glucose difference (2 standard deviations) between reference and interstitial glucose of -10.5 (41.8) % for GRT, 20.2 (55.9) % for GDS and 6.5 (35.2) % for MD, respectively. Overall MAD (interquartile range) was 1.07 (0.39; 2.04) mmol/l for GRT, 1.59 (0.54; 3.08) mmol/l for GDS and 0.76 (0.26; 1.58) mmol/l for MD. Overall MARD was 15.0 (5.6; 23.4) % (GRT), 19.7 (6.1; 37.6) % (GDS) and 8.7 (4.1; 18.3) % (MD), respectively. Total sensor failure occurred in two subjects using GRT and one subject using GDS.
The three investigated technologies had comparable performance. Whereas GRT underestimated actual blood glucose, GDS and MD overestimated blood glucose. Considerable deviations during daily life meal glucose excursions from reference glucose were observed for all three investigated technologies. Present technologies may require further improvement until individual data can lead to direct and automated generation of therapeutic advice in diabetes management.
比较两种市售的皮下葡萄糖监测设备（Guardian RT，GRT；GlucoDay S，GDS）和标准微透析（CMA60；MD）在 1 型糖尿病患者中的准确性。
7 名男性 1 型糖尿病患者在 26 小时内模拟真实的进餐葡萄糖波动进行了研究。三个系统的导管插入腹部皮下脂肪组织。对于 MD，每隔 30-60 分钟采集间质液进行离线葡萄糖测定。每隔 15-60 分钟采集参考样本。所有三个系统均前瞻性地与参考值进行校准。中位数差值、中位数绝对相对差值（MARD）、中位数绝对差值（MAD）、Bland-Altman 图和 Clark 误差网格用于确定准确性。
Bland-Altman 分析表明，GRT 参考值与间质葡萄糖之间的平均葡萄糖差值（2 个标准差）为-10.5（41.8）%，GDS 为 20.2（55.9）%，MD 为 6.5（35.2）%。GRT 的总体 MAD（四分位距）为 1.07（0.39；2.04）mmol/l，GDS 为 1.59（0.54；3.08）mmol/l，MD 为 0.76（0.26；1.58）mmol/l。GRT 的总体 MARD 为 15.0（5.6；23.4）%，GDS 为 19.7（6.1；37.6）%，MD 为 8.7（4.1；18.3）%。使用 GRT 的两名受试者和使用 GDS 的一名受试者发生了总传感器故障。
三种研究的技术具有可比性。GRT 低估了实际血糖，而 GDS 和 MD 则高估了血糖。在所有三种研究的技术中，在日常生活进餐葡萄糖波动期间都观察到了相当大的偏差。目前的技术可能需要进一步改进，直到可以直接生成个性化数据并自动生成糖尿病管理中的治疗建议。
